Triumph Hinckley FAQ

This is a blatant copy of a good old FAQ I found on It’s a collation of information gathered from a mailing list that used to be maintained by a US chap called Steve Manes. Also Kit of fame used to host it on his site back in the day. It only seemed right that this information wasn’t cast side and has been revived here verbatim for posterity only.

It also helps that a lot of this info is relevant to your MK1.

1. Introduction and Administravia

1.1. How do I get on to and off the list?
1.2. How does the mail list work?
1.3. Is there a WEB server?
1.4. Help!
1.5. How can I contribute here?
1.6. Is this FAQ freely copyable?

2. Information on the Company

2.1. History
2.2. Addresses and phone number of the factory?
2.3. What model ranges has Triumph produced?

3. Operating tips

3.1. How do I get my Triumph to start on cold days?
3.2. How do I stop my gas/petrol tank cap from whistling?
3.3. What causes the excesive wear on a Tiger’s rear brake pad ?
3.4. How about some riding tips?

4. Maintainence

4.1. Valve Adjustments

4.1.1. Is it hard to do the valve adjustment yourself?
4.1.2. How about cheaper valve shims?
4.2. Misc.

4.2.1. Is there an aftermarket oil filter that works with the triumph?
4.2.2. Does anyone know the paint codes for Triumph Dupont paints?

5. Aftermarket accessories

5.1. Where are good sources for after market accessories?
5.2. Pipes & slip on mufflers
5.3. Carburator modifications
5.4. Fairing and windscreens
5.5. Seats
5.6. Handle bars and clip-ons
5.7. Bolt-on Horsepower
5.8. Body Parts

6. Performance modifications

6.1. Engine modifications

6.1.1. Introduction Why should I make my bike go faster? I want more power in my new Triumph. Any ideas? A quick review and horsepower poententials Wow, just how much horsepower is in those triples? The Standard Disclaimer
6.1.2. Jetting Summary of jetting experiences Any thoughts on Dynojet kits and Triumph triple engines? What about Dynojet kits on the fours? What about just massaging the jets and not going for the expense (and drilling) that a jet kit requires? What if i just want to spruce up the power band with even less work and eliminate the cold-starting problem we’ve got here in the U.S. without seriously mucking about?
6.1.3. Airbox/Carburation Are the airbox baffles superflouous? Shouldn’t I just take them out to let the engine breathe better? How about adding separate ‘pod’ filters instead of the airbox? Know anything about how flatside carbs might work on the triples? Anyone have any experience with the K&N filter replacement?
6.1.4. Exhaust What about the Sebring 3-into-1 pipe for the Triumphs? What about other exhaust systems?
6.1.5. Ignition How can I mess with my igniter to raise the rev limit?
6.1.6. California-spec Bikes How are the California-spec bikes different?
6.1.7. Tiger, Thunderbird, Adventurer What about modding the lower-hp/higher-torque Tiger, Thunderbird and Adventurers?
6.1.8. Personal experiences Grant Parsons ( Jim Bazz davet@valiant.CDS.TEK.COM Richard van Laar ( Carlo Klein ( Rein Suyker ( Guss Schutgens ( John Fitzwater ( Nigel Nicholson
6.1.9. Questions in search of answers Why do the stock jets use different needles while Dyno testing reveals all cylinders should use the same needles?
6.2. Suspension modifications

6.2.1. Front Suspension How can i firm up my Sprint’s (or other non-adjustable) stock forks?
6.2.2. Rear Suspension
6.2.3. Tires
6.2.4. Personal experiences Grant Parsons (

1.   Introduction and Administravia

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1.1. How do I get on to and off the list?
To subscribe send mail to to get onto or off of the list. In the body of the email either put:

subscribe triumph-digest
unsubscribe triumph-digest

That’s “triumph-digest”, not Triumph. There is no direct mail reflection for the Triumph list… digests only. Subscription requests to Triumph will be ignored.

After subscribing, should you wish to subscribe to the list and wish to complete the following optional questionnaire, please send it directly to, not the list.

Motorcycles Currently Owned: Make Model Year

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1.2. How does the mail list work?

A mailing list is a cooperative beast. One person (that’s me) maintains it but everyone contributes. Messages sent to the list address are queued and a digest of the day’s messages are sent out to all subscribers simultaneously at 5PM GMT. If that day’s message queue grows to over 40,000 characters, multiple digests may be sent.

Replies to messages posted to the list will automatically go to the list and not just to the originator. If you wish to send a reply only to the originator of the message, then send it directly them.

IMPORTANT: because of misbehaving mailers and mailing list spammers, posts to the Triumph digest are RESTRICTED TO SUBSCRIBERS. This means that you may only post from the address you originally subscribed under. If you find that your posts are not making it to the digest or you receive notification from the mailing list software that your post was rejected for “non-member submission” your email address may have changed without your knowledge. This is common with enterprise mail domains and large ISPs. In this event, contact me to fix it.

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1.3. Is there a WEB server?
The official answer:

Not yet, but one is in progress and should be completed by October or November. It will provide a picture record of the models built by the Hinckley factory since it started production in 1991 model year, as well as reference information. If you have any information/photos which you would like contribute, please send them to me.

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1.4. Help.
If you ever need help, send the list administrator an email message to ( with Triumph Help as the subject.

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1.5. How can I contribute here?
Eventually the DynaFAQ will support user-level editing. In the meantime, the best place to send general questions and/or answers is directly to the Triumph mailing list since all messages are archived and will eventually be merged into the FAQ.

Much of this information in this FAQ has been compiled by the following people. Until the DynaFAQ becomes the officially sanctioned FAQ list for the Triumph group, please contact these people first:

List-related questions should be sent to Steve Manes,

Any info you want to share about jet kits and tuning should be mailed to Grant Parsons

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1.6. Is this FAQ freely copyable?
Most of the information in this FAQ was compiled by Grant Parsons. Here is what he has to say about copy rights:

Information wants to be free. Do it up. I’d appreciate it if you let me know if it’s reprinted in electronic form on the Internet, and in general it’d be nice if it you keep the entire document intact if you reprint it to retain some sense of the context.

To reprint all or part of this in a very public forum, like, say, a magazine, you should check with the individuals who submitted information before doing so. But if all you want to do is cut something out and e-mail it to someone who wants to know, have a blast. That’s what this is here for.

Legally, each of the people who contributed to the FAQ retains the copyright for their own words. The compilation of those submissions is also copyrighted by Grant Parsons.

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2. Information on the Company

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2.1. History
After the original Triumph Motorcycle company went under in 1983, a Mr. John Bloor purchased the rights to the Triumph marquee, and started to pull together a team of designers and engineers. Over the next five years Mr. John Bloor began investing in the development of a new line of British motorcycles. In order to be successful he felt that he needed to provide a very reliable machine, using as many top-quality off-the-shelf parts as possible, and manufacturing the rest with the most modern tooling and best materials available at the time.

Quality and efficiency have been the watch-words right from the start and continue to be the defining characteristics of the firm. One of the most salient features of the machines and manufacturing process is the so-called ‘modular concept’, which means that most of the major components are interchangable across the range. Basic engine configurations are 749cc triple (76mmx55mm); 885cc triple (76x65mm) and 1180cc four (76x65mm). All the frames are basically the same (the differences being to do with the bracketry and such like), as large diameter spine frames with the engines as stressed members.”

It has been reported that Bloor invested over 76 million pounds, all of it his own money, into the company. John Bloor did not go elsewhere to raise the money. All the money invested was his money. He had his own ideas about the direction the company should take and has not risked compromising his vision by pleasing banks/financiers.

The new factory was build outside of the town of Hinckley. Hinckley is in Leicestershire and is no more than 20 miles away from Meriden, where the original factory stood (now a housing development). Construction was started in 1988 and the first motorcycle was built in 1990. At that time, Triumph had fewer than 50 employees and produced around five bikes a day.

The company introduced their new machines at the Cologne motorcycle show. The first model reached the UK dealerships in late May of that year. Currently, Triumph employ around 350 people, of whom 36 are occupied full-time in research, development and design. They work in two shifts, from 7am to 11pm, producing around 80 bikes per day for 35 different countries around the world. To date Triumph have produced almost 34,000 machines in their various guises, the majority having been the ‘ace in the pack’ 885cc 120 degree triples. More and more of the bikes are made in house every day, but the current 15 acre site is bursting at the seems. Triumph is in the process of building another newer, larger factory on a 40 acre site, which is scheduled to go into production in early 1997.

Mr. Bloor wanted to control as much of the process as possible, in order to ensure the overall quality of the Triumphs. At present, 80 percent of the bikes are made in the factory, and it is increasing as each year passes. Part of the success of the company is the high level of modularity between the models. Since the designers started with a clean sheet in 1987, they chose a modular design upfront. This means that of the 2500 parts used in say a Daytona, 87% can be used to build a Trophy, Spring or Speed Triple. The engine comes in either a 3 or a 4 cylinder configuration and either a short or a long stroke.

Information regarding production volumes is hard to get, however here is come second hand information. Presently, about 70 bikes are build a day at the Hinckley factory, or one very 7 minutes. In response to the success of their bikes, a second factory is in the process of being built which will have a capacity of about 50,000 bikes per year. The present facility has a capacity of around 15,000 bikers per year. (Note, this is an estimate on my part based on 70 bikes per day and assuming 210 workday per year).

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2.2. Addresses and phone number of the factory?

Triumph Motorcycles Limited
Jacknell Road
Dodwells Bridge Industrial estate
Hinckley, Leicestershire LE10 3BS
United Kingdom
Tel: (01455) 251600

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2.3. What model ranges has Triumph produced?
1991 750 and 900 Trident
750 and 1000 Daytona
900 and 1200 Trophy
1992 Same as 1991, with some paintwork changes
1993 750 and 900 Trident
900 and 1200 Daytona ( The 750 and 1000 were replaced)
900 and 1200 Trophy
900 Sprint
1994 750 and 900 Trident
900 and 1200 Daytona
900 and 1200 Trophy
900 Sprint
900 Speed Triple
900 Super III

NOTE: The Daytona, Trophy, Sprint, Speed Triple and Supper III changed over to Italian made three spoke wheels in 1994.

1995 750 and 900 Trident
900 and 1200 Daytona
900 and 1200 Trophy
900 Sprint ( the tail was restyled)
900 Speed Triple
900 Super III
900 Tiger
900 Thunderbird
1996 750 and 900 Trident (Both received new lighter, more adjustable rear shock & the 900 got a more adjustable front end.)
900 and 1200 Daytona (Change to forks, new rear shocks, Brembo brake discs and calipers).
900 and 1200 Trophy (new fairing, Sprint tail, integral paniers, frame-mounted clocks with Chrome bezels).
900 Sprint (New rear shock and forks).
900 Speed Triple (See Daytonas, plus an added 6th gear).
900 Super III (See Daytonas)
900 Tiger (New luggage rack).
900 Thunderbird – Triumph ‘retro’ model with wire wheels comes in British Racing Green with Cream and hand-painted pin striping.
900 Adventurer – Custom Thunderbird with bob rear mudguard, single/dual seat option, lots of chrome, lots of factory accessories.

Note: Both the T-Bird and Adventurer got oval section swingarms.

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3. Operating tips

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3.1. How do I get my Triumph to start on cold days?
[[[ In heavy traffic or on very cold days my battery have enough power to the bike’s lights but not enough for the iginition and started, any suggestions? ]]]

Here are two suggestions:

A) Start the procedure with all setting on off, then in this order:

  1. Choke on
  2. Kill switch on
  3. Depress & hold starter switch
  4. Turn on Ignition
  5. Kill switch off

This puts a spike of current through the starter when the kill switch is disengaged.

B) Take the bike seat off and remove the light fuse and start the bike normally.

Remember not to pump the throttle, as the choke on the Trumps Mikunis uses a separate enriched fuel circuit and hence does not benefit from throttle activity. On the contrary, opening the throttle will just lean the mixture right off at this stage. The throttle should not be used at all until the choke circuit has done its work and the engine is firing.

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3.2. How do I stop my gas/petrol tank cap from whistling?
You can’t. It’s a safety feature which prevents too much gas/petrol from being spilt when the bike is over on it’s side.

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3.3. What causes the excesive wear on a Tiger’s rear brake pad ?
Occasionally, a few Tigers comes from the factory with too little free play at the rear brake lever. When the bike is cold, the lever appears to have enough freeplay. However, when the pads/discs/fluid warms after a few applications, the fluid expands, pushes the master cylinder piston back, which uses up all the free play… . The rear master cylinder piston can’t move any further, so the caliper piston obligingly moves for it, and the pads start dragging on the disc. This causes more heat, the fluid gets hotter, expands even more, etc etc. The eventual result is a trashed set of pads and rear disc. Next time you’re out riding, check your rear brake pedal has freeplay when it is warm. Hope you find this useful in preventing wallet fatigue.

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3.4. How about some riding tips?
Everyone can be helped by reviewing the basics. If this is remedial for you racers, just skip it. :-)

John Fitzwater said:

Just thought I’d post a few things I’ve learnt lately regarding riding techniques and suspension set up on Triumphs. Recently we sold a 95 Sprint to a local guy and his wife. They loved it at first, but soon Gill, the guy’s partner was telling us that Rick was feeling ill at ease on the bike. One Saturday we organised a shop promotional ride and I followed Rick for a spell. It was scary – he was running wide on a lot of corners and definitely not at one with the Sprint. Before I could pull him aside at the next stop, he wadded the bike on the 3rd S in a series of three along the side of a steep river bank. Apart from lots of busted Nightshade fairing pieces everywhere, there was a good deal of shattered pride lying about the place too. Rick fixed the bike up eventually, but at only 3000km, he told us he wanted to sell it cos he couldn’t get to grips with it. I went to see him and Gill, and asked if he would let us have a play with the bike for a while. If he rode it after we had set it up and still didn’t like it, then we would proceed with the decision to sell. I rode the bike and it was not very nice – it wanted to run wide on medium speed corners, and was very vague on slow corners – no feedback at all. First thing we checked was his tyre pressures – 25lb front, 35lb rear. Obviously way too low. Correcting this gave an immediate big improvement in the steering, but still the vague feeling persisted. Checked the rear suspension setting – spring preload on 2, damping on 3. We put the spring up to 4.5 and damping up to 4. Now we were getting somewhere – the bike really started to feel nice. The forks were diving a lot – while we’re waiting for the Maxton fork conversion to turn up, we have put in another 50cc of oil in each leg. This has reduced dive under braking, but it still needs the fork kit (when we’ve fitted this I’ll let you know the results – airmail from the UK aint wot it’s cracked up to be!). We now have a nice handling bike, however….

Two things strike me when riding the Sprint. I’m 5’6″ (so is Rick). Firstly, my arms are almost locked straight when I’m holding the bars – it’s a big stretch. When going through tight twisty corners, the bars want to roll away from me to a point where my lack of remaining arm/shoulder travel then restricts the steering lock. Unless I lean forward to give more arm travel, I am actually preventing the bike from leaning into the corner, hence we start to run wide. I’d like to fit a Storz superbike bar kit, but Storz have this daft (and non-negotiable) way of freighting to NZ where the freight costs more than the price of the kit(but that’s another story…). I’ll get around it.

Secondly, a lot of new Triumph riders have jumped straight off Bonnies, Tridents, Nortons etc. Grab a handful of front brake mid corner on a skinny 19″ wheeled underbraked Commando, and nothing will happen (hell, it’ll

probably accelerate!). No ill effects at all. Do it on a 17″ wheeled Hinckley Triumph though, and yeehaa, where’d the corner go? Suddenly the bike stands up and heads for the ditch on the other side of the road like a laser guided missile. This is what did Rick in. The first S, no problem, 2nd one, whew, got around that OK, 3rd one? Beejasus, I’m not gonna make it! – suck the seat cover up your sphincter, grab the front brake and….the bugger wont turn. Eyes the size of saucers (permanently enlarged, in fact) you head toward the fence until there’s no road left. Ouch.

Now if you’ve been raised on a diet of modern 16″ or 17″ wheeled bikes, you’re probably reacing for the delete button by now. If you haven’t the moral is, don’t try to turn and brake at the same time. Speshly on a new Triumph! Brake first, let go of the front brake lever, and get on with negotiating the corner. Apart from anything else related to steering geometry and tyre width etch, the tyre can concentrate on turning forces, not braking forces as well.

Two quick other things we’ve learnt lately. Tigers handle heaps better with the forks dropped 30mm through the yokes and the rear spring set quite firm.Not that they had a problem in the first place, – with these settings they become a weapon.

Daytonas – if you’re vertically challenged, try resting your chest on the fuel tank when tackling fast twisties. Rest your forearms along the top sides of the fuel tank. Countersteer hard to make the bike change direction fast, then relax your arms and allow the bike to turn into the turn itself, using footpeg and knee pressure to increase or decrease the rate of turn. Cos you’re leaning on the tank, it will compensate for short arms, and you’ll find the bike wont run wide. We’ve suggested this technique to a few of our Daytona customers lately and they have come back with grins a mile wide. Keep those arms bent!

….To which Grant Parsons adds….

not to turn this into ‘triumph riders’ school’ or anything, but to john’s excellent advice i’d add the following for people new to the triumphs…..

yes, these are heavy motorcycles, but they can be ridden fast with a bit of accomodation. sportbike types can hit the d key now, but older and returning riders would benefit from some acclimation time on the triumphs to learn what they want.

even the touring jobbies perform more like sportbikes, and since they ride so well, you’ll tend to find yourself approaching curves at a healthy pace. it’s key to get the braking done before the corners. all bikes benefit from a healthy dose of throttle through the corners, but on the triumphs this is imperative. brake, turn in for corner and gas it _through_ the corner. you should be accelerating through the corner. (keith code alert! ;-) to paraphase code (get his book, _twist of the wrist II_), if you didn’t lose traction going in, getting on the gas will not make the bike worse, it will make it handle. you’ll notice this immediately once you try it. if you’re going in too fast to comfortably gas it once your leaned over, slow your entry speed next time and see if it works better. on the gas everything smooths out and life is grand. off the gas or coasting through to the apex can be scary — on any bike.

i ride a sprint, and i can attest to the fact that it seems to want to straighten up when the brakes are applied hard in a turn. you don’t want to be doing this anyway: braking and turning is asking the front tire to do too many things and can lead to disaster. to really move out on this bike, you might benefit from upper body lean-in and/or hanging off just a bit, along with the aforementioned brake-first/gas-through mentality. braking mid-corner is asking for trouble.

on a recent ride this weekend in the mountains with some friends on sportbikes, a buell and i ran away and hid from a couple of 900rrs, a ducati paso and a goof2. i had finally “gotten it” on this bike and was riding through corners fully relaxed, slightly hanging off, on the throttle, letting the bike do the work. i was shocked when i felt the peg hit the asphalt on one corner, but it told me i was doing it right. (btw, this was on a road we knew well, with few driveways, that we had already ridden one way and were coming back, so we knew what to expect; not a perfect situation, but _much_ better than riding it blind. ymmv.)

as i was on the sprint, i was more or less amazed at our ability to leave the other ‘pure’ sportbikes behind. this bike will flat haul, but only on its own terms. it’s taken me more than 4k miles to find its terms, but now that i have, it’s gotten much easier. but i’ll always be learning.

also, in the u.s., an msf course, if you’ve never taken one, is a must. i took one after riding for more than a decade. i was flat amazed_at what I learned. keith codeUs book is an excellent resource as well.

for those who can afford it, i’ve heard track schools are just the thing to train your reflexes. the rest of us read keith code and take an msf course and as always, ride within our limits.

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4. Maintainence

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4.1. Valve Adjustments

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4.1.1. Is it hard to do the valve adjustment yourself?
Valve adjustments seem to run in the $150-$250 range here in the U.S. It’s not impossible to do the job yourself if you’re a reasonably proficient mechanic, but you’ll need a special Triumph tool to do it. Here’s my

…actually, you can. only one special triumph tool is required, and although it looks spindly as heck, it does the job wonderfully. mine cost $61 (conveniently just at 1.5 hours of time ;-) . of course, that assumes you have a micrometer, a good one of which would run you at least another 1.5 hours of shop time. i didnt’ have either, but buying both put me well under the quotes i heard for 6k services around here.

i’ve heard from two separate mechanics that very few shims needed replacing at the 6k generally. however, that wasn’t my experience, and i’d be curious to know how many shims got replaced for others here.

more than you want to know…

i checked my valves at 5.5k mi., since i had planned a long trip and the 6k point would fall far from home. at that point, everything was technically in range (.15-.20mm exhaust; .10-.15mm inlet), although three valves were nearing the edge of the limit. since i didn’t have a micrometer and everything was technically in, i put it all back together and checked it again when i got back and then procrastinated a while, at 7.5k mi., just to be sure.

at that point, the three tight valves had definitely gone out of the range. no biggie, but six more were were just about to the edge of the service limit.

well, since the next scheduled valve check isnt’ for another 12k mi. (at 18k), and i was a bit worried about the valves nearing the low end of the range, i reset not only the three that were definitely out, but also the six that were nearing the end, putting them back up to the middle of the range, to allow for any loosening (unlikely) or tightening (likely)..


in light of what seemed to me to be a lot of wear immediately after the 6k point, i’d humbly suggest asking the mechanic to change not only the shims that are out, but the shims that are getting within .01 or .015 of being out-of-spec, to give them plenty or room to wear in over the next 12k mi. of unchecked riding. personally, i plan to check my valves at intervals shorter than the recommended ones. better safe than sorry.

also, it couldn’t hurt to ask them to record for you what each valve clearance was, both before and after they swap. it will tell you a lot about how your engine is wearing in.

also, it might be obvious, but make sure you take the bike in the night before; the adjustment is supposed to be done on a _cold_ engine. a hot or warm engine would make the valves seem incorrectly tight.

also, fwiw, shims here cost $5.50 us. old ones make neat tiddlywinks. if they charge you the full $5.50, i’d ask to keep the old shims, as i think stuff that comes out of engines is just cool. but i’m kinda weird that way. ;-)

also, if anyone plans to do the job themselves, do yourself a favor and stuff a rag in where the cam chain runs down to the crank. an errant shim could easily drop down in there if you’re not careful. it didn’t happen to me, thank goodness, but one came close enough to stop my heart and took at least 1.5 hours of shop time off my life ;-)

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4.1.2. How about cheaper valve shims?
Carlo, ever the experimenter, comes to the rescue again:

The valve shims are exactly 25.0 mm in diameter, and I’ve used some off a Yamaha XJ600 from the local Jap-shop, maybe there are more compatible bikes. Bring your vernier caliper and just check the diameter, you should be fine as I believe the material hardness should be about the same.

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4.2. Misc.

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4.2.1. Is there an aftermarket oil filter that works with the triumph?
Carlo Klein says:

I’ve just bought an alternative oil filter element for the Daytona for about a third of the original Triumph price. It’s from Meiwa, designed for all Honda 4 in line engines and Kawasaki K400/440/550/650/750, ZX550/600/750/900/1100 – cost about $6.

The included rubber O-ring seals don’t fit, so you have to get the original Triumph parts: #3600025 (large) and #3600003 (small), about $1 each.

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4.2.2. Does anyone know the paint codes for Triumph Dupont paints?
John Fitzwater does All you need to do is take these numbers to your friendly neighborhood Dupont dealer, give him the number and some money, and he’ll giveyou the paint. Triumph dealer’s don’t always stock it.


Colour CodeColour NameDuPont RefC500C600C6000
BEC089Assam BlackH0016XXX
BEC268British Racing GreenH0015XX
BEC368Cherry Red MetallicH0013XX
BEC650Cherry Black MetallicH0014XX
BEC858Lancaster RedH0006XXX
BEC918Charcoal Grey MetallicH0010XX
BEC1067Caribbean Blue Metall.H0009XX
BEC1088Radiant RedH0012XXX
BEC1136Burgundy MetallicH0011XX
BEC1258Midnight BlueH0007XXX
BEC1259Oxford BlueH0008XX
BEC1342Diablo BlackH0947X
BEC1343/HAABrit.Racing Green Met.H0944X
BEC1296/CEBCandy Apple MetallicH0951X
BEC1402Flat White (u/coat)H3031X
BEC1479/CFBPimento RedH0950X
BEC1514Racing YellowH0948X
BEC1543/PLBFlat BlackH0953X
BEC1657/EBAFireball OrangeH0946XX
NB: C500 2K Solid Colour
  C600 Clear Over Base
  C6000 Medium Solids Over Clear Base

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5. Aftermarket accessories

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5.1. Where are good sources for after market accessories?
From the List FAQ:

While in its infantile stages, a limited number of vendors are offering some products. Your Triumph dealership will have more goodies from the factory available shortly, but one of the most famous Triumph dealerships from the early days is none other than _Big D Cycle_ of Dallas, TX. You can contact them at 214.339.2285 for the latest performance products available for the modern Triumphs.

See also the section on aftermarket parts for a list of manufacturers.

From the Tuning and Jetting FAQ: keeps a list. I hope he doesn’t mind my reprinting it here. If you have anything to add, e-mail him, please.

Here’s a list of Triumph performance part aftermarket suppliers. If you hear of more let me know. Hope it helps, Good Luck!

Triumph America Ltd800-743-3874Everything you heart desires
K&N Engineering909-684-9762Jet Kit, Air Filters
DynoJet406-388-4993Jet Kit
Factory415-721-4964Jet Kit
D&D800-843-8961Exhaust: Slip-on
Micron708-963-5200Exhaust: Slip-on
Yoshimura R&D714-628-4722Exhaust: Slip-on, 3-1 System
Sims & Rohm916-674-9123Ignition Advancer, more to come
Air Tech619-757-3366Fairings
Luftmeister310-529-6420Brake Lines, Exhaust, Turbo Kit
PI Motorsports818-249-5707Staintune Exhaust, Taylormade CF Bits, Clip-ons, Footpegs, etc.
RaceTech909-594-7755Fork Springs and cartridge emulators
Stortz Performance805-641-9540Handlebar Riser Kits
Lockhart-Phillips800-221-7291Steering Damper, Kevlar BrakeLines
Indigo Sports770-719-3800Dymag Road Wheels
PDQ Motorcycle Dev01628-667644Exhaust: Laser, Johnson Slip-on K&N Filters, Dymag Road Wheels
Jack Liley Racing01932-224575Exhaust: 3-1 System Remapped CDI, CF Bits
Muller Technik01909-482670Exhaust: Slip-on, 3-4-2-1 System
Saxon Racing01372-843802Shocks, Forks, CF bits
Maxton Engineering01928-740531Koni/Maxton Shocks, Fork revalving

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5.2. Pipes & slip on mufflers

GIACAMOTO – both 4 into 1 & pair of slip ons available. 4 into 1 system is 699.00 carbon and 599.00 aluminum. Slip ons are 679.00 carbon and 559.00 aluminum. I’ve called Action Cycle in Florida for further info – they don’t really have anything. No specs, pictures, etc. G pipes for Ducati are wonderful but I’m hesitant to shell out 700.00 without additional info.

MICRON – carbon and aluminum slip ons for the 4 cylinder & 3 cylinder models. I *think* they may have a complete system for the triples. Slip ons are 799.00 carbon and 499.00 polished aluminum. They do recommend rejetting the carbs since these silencers are a LOT less restrictive. Their carbon cans are top notch quality for finish, etc. Close to the Super III pattern. Per Micron, they are NOT going to build a 4 into 1 for the 1200′s. They maintain the motor is best suited for a 4 into 2, ie; better midrange – it’s not a peak HP motor. Main obstacle is the stock cans. VERY helpful people.

YOSHIMURA – Zyclone slip ons in carbon for 476.00 or 296.00 for aluminum. Zyclone’s are about the same volume as Vance & Hine’s SS2R pipes. For additional 80.00 you can get the ZRS baffles – about 4 decibels less noise. They have both street and competition baffles availabole too. NOTE: Per Yoshimura – their pipes offer NO INCREASE in performance- strictly better sound and considerable weight savings. Their cans are also available “plain” – no Yoshimura plates riveted on – just specify this. They are also developing a 4 into 1 system for the 1200′s. I was told Triumph of America is more than encouraging them to market the system. They won’t unless they KNOW they can sell at least 50 + systems. START CALLING!!!

D&D – slip ons for both the 900′s and the 1200′s. I don’t know the pricing or much else about them since I personally don’t care for the looks. In *MY* opinion the carbon canisters are less than attractive – the carbon weave looks too sloppy – like it came out of a chopper gun and I don’t care for the finish on the lead-in pipes either. A comparison of attention to detail, fit and finish between these silencers and the Microns is an absolute joke. They may work well, but… (AGAIN, this is MY opinion – spend YOUR money where YOU choose).

SIMS & ROHM – currently no complete systems or slip ons for the 1200′s. They are focusing on the triples as of right now. This could change by Summer.

KERKER & SUPERTRAPP – no plans to do anything at all. They don’t see a market – short sighted buggers!

VANCE & HINES – same as Kerker and Supertrapp.

MUZZY – ditto adds:

I have found a couple of others. Stainetune makes slip-ons and 4into1 systems. They could not give me any specs on them yet. Their carbon and stainless slip-ons look pretty good,but at 795.00 and no perform- ance specs I`D wait on them. Luftmeister has a 4 into 1 system in the works. When I talked to them last month (that would be Dec. ’95) they said that they would be available soon. They claimed up to 10%hp gain, with a jet kit. The price at that time was going to be 450.00 including the jet kit. A reasonable price if it works. adds:

Whilst looking for a replacement silencer for my ’92 Trophy-3 I found `Gazelle Exhausts’ based in Roshill, Pembrokeshire, Wales.

A basic cone-onto-can type silencer costs from 135 UKStlg + 25 UKStlg for the end cap = 160 UKStlg + V.A.T @17.5%.

It uses louvered baffle tube acoustic insulation stainless steel metal fibre wool (it say’s ‘ere) and there is an e-mail address too – says:

The Yoshis were reported in the Dutch magazine Kicxstart to weigh 4.8 kilograms. They cost 875 Dutch guilders, or about $550 US says:

My local dealer has a pair of the CF versions. They look very nicely made. He wants $495 for them, which isn’t exactly -nothing-, unless you’re a wealthy Dutchman.)

From unknown sources:

Triumph has a three into one pipe which is all stainless and made by Sebring in Germany. By recent accounts, three into one pipes kill the midrange but work pretty well at top end.

PI Motorsport also has a three into one pipe for the Daytona 900. Contact them via email at or call 818.249.5707.

Stainture in Australia has an excellent reputation for quality products and many Ducati owners have purchased their products although they make of them for many other marques and models. They have complete systems, header pipes, Quiet Mufflers, Sport Mufflers and Mufflers … also willing to modify them a bit to customer specifications if not too radical, that is. Contact Stainture in Mittagong, NSW, Australia phone 048.713188, fax 048.713851.

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5.3. Carburator modifications
“Lilley” chip is available for the Sprint, and all other 900 models – it raises the rpm limiter to 10300, plus has a faster processor speed giving “better response” according to the maker. Lilley’s claim 95bhp is available when used with their 3/1 pipes. The pre-94 chip is much cheaper than the post 94 chip (late igniter boxes have PVM written on them). The chip/Dynojet kit also gave a nice torque bulge at 5500rpm. Contact Jack Lilley Motorcycles near London, England (tel: 0932 224574)

DynoJet reputedly work well with the 900 triples, adding a few extra hp in the already good mid-range, and crispening up the throttle response considerably. Contact DynoJet directly at 406-388-4993 or a dealership.

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5.4. Fairing and windscreens
Sprint Manuf. of Warminster, in the UK have a number of faring for the Tridents (including a tall windscreen and a dual headlight model) plus the Daytona front end (which resembles an Aprilia RS250), also Sprint fairing lowers, extended front mudguards and other sensible stuff –all painted w/genuine Triumph factory paint w/3 coats of laquer.

Sprint Manuf.
30B Upton Lovell
Warminster, Wiltshire BA12 OJW
tel-0985 850821 fax-0985 850963

Corbin sells a replacement windscreen in clear and smoke for the ’91-95 Trophy. Contact Corbin Triumph in the USA 800.665.9874

PowerBronze makes ahalf-fairing for Trident and Sprint. Contact:

Powerbronze Ltd
44 Brook Lane
Ferring, Near Worthing, West Sussex
BN12 5JD, UK
Tel: 44 1903 507 300 Fax: 44 1903 507 683

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5.5. Seats
Corbin has a wide range of styles available for models. For a free catalog contact them at 800-665-9874, fax 408-633-1512, or email They also do custom seats with matching Triumph colors.

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5.6. Handle bars and clip-ons
Rocket M/C in San Diego (619-239 3256) has a bar kit for the Speed 3. It is just as nice as the Storz item for the Daytona. It requires drilling and tapping 2 holes (comes with jig and guides).

PRO ITALIA has handlebar for the Speed Triple. They move the grips up by 3″ and back 1″ from the stock position and are made of billet aluminum. Very pricey but include extra-long stainless steel brake line you’ll need to complete the project. Contact Pro Italia at (818) 249-5707.

Storz Performance has a handlebar conversion kits for most models. They offer a specially design one for the Daytona and Super III which raises the bar without requiring any modification of the fairing. Contact them at 805.654.8816.

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5.7. Bolt-on Horsepower
A big bore kit was developed by Paul Taylor, Taylor Made Racing. He’s the big cheese for the Saxon Triumph that has been racing the BEARS series. The kit includes pistons, sleeves, and head gasket, and the cases have to be machined. It takes a 900 to a 980. Price in the US is $1299. Contact Pro Italia at (818) 249-5707.

Spark Advancers True “bolt-on” horsepower! Adjustable spark advancers, from -10 to +10 degrees, are available for both the 900 and 1200. Made by Sims & Rohm, available from Corbin’s Triumph 800-665-9874, fax 408-633-1512, email

Luftmeister in Southern Calf. has developed turbo charger for the Daytona 1200 which they say puts out over 275 horse power, and a top speed of over 200 mph. The turbo is very experimental. Contact them at 800.275.2129 or 213.408.0411, or fax 213.408.4587.

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5.8. Body Parts
None yet.

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6. Performance modifications

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6.1. Engine modifications

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6.1.1. Introduction

back to top Why should I make my bike go faster?
In the words of the immortal Hunter S. Thompson:

“Some may say that slow is good – and they may be right on some days – but I am here to tell you that fast is better … It will always be better to be shot out of a cannon than squeezed out of a tube, and that’s why God made fast motorcycles, Bubba.”

back to top I want more power in my new Triumph. Any ideas?
There are lots out there. Any two tuners will offer different solutions, and they they all may work to varying degrees. As with any type of engine mods, you pays your money and you takes your choice. But the folks at are a trustworthy bunch. Here is some information from them and some from me. I’ve done a fair amount of carb modifying, on my bikes over the years and on friends’, although I’m not a professional tuner by any stretch. Some of the folks here are, though, so keep that in mind as you read on.

The general consensus is that the easiest way to get more horsepower is to monkey with the jets for a few hp gains (some people report 4.5 or more hp from jets alone), and then pipes if that’s not enough (maybe as many as 10-15 hp when combined with jets). One tuner has reached 102 rear wheel horsepower on a triple with jets and the stock pipe, and even higher with additional mods like a pipe, ignition advancers and such.

On U.S. bikes, you can get very good results with jet-swapping, as EPA regs strangle our engines; european bikes, since they’re in a better state of tune to begin with, are harder to coax gains out of — but it’s not impossible, and even they can benefit from carb tweaking.

There are two main ways to mod your carbs: the jet kit way, or the do-it-yourself way. Each replaces the jets in your carb, a more or less home mechanic thing that a reasonably proficient tinkerer should be able to accomplish with a service manual. If all you do is swap jets, the procedure is reversible if you don’t like the results. (My service manual from Triumph is well-done and worth even the $53 I paid for it.)

Each method of tuning has pros and cons. And although each might give you gains you can feel with your own posterior dynometer, turning your bike over to an experienced shop with a dynometer is a good thing to do once you get it in the ballpark. In particular, the new Triumphs, like most modern bikes, are very sensitive to the CO level.

Jet Kits: These are made by the likes of Factory, Dynojet and a few other aftermarket companies. What they do is take a new bike, put it on a dynometer and tune for power. Then they take whatever jets they wound up with, put them in a kit, and sell it to you. Dynojet’s Triumph triple kit goes for something like $140 ($160 for the fours), which ain’t cheap. But you do get real dyno-testing behind it.

Jet kits usually contain bigger main jets, differently tapered needles than stock, and sometimes different springs. They often also come with a drill bit to drill out the hole in the carb slide, to allegedly give better throttle response by allowing the slide to move up and down more quickly with changes in vacuum pressure. Also included is a drill to drill out the (U.S., at least) dork caps over the air screws, so you can turn them out to something closer to euro spec. Air screws control cold- bloodedness, among other things, and U.S. bikes are turned way in for emissions. Used with or without a more free-flowing filter, kits can give real gains.

The problem is where the gains are. Lots on top probably won’t help you if you don’t ride on the track. Generally, for street use, you want big gains in the mid-range. If you’re buying a kit, ask the tech rep at the company what kind of gains you can expect and where they’ll be.

Factory jet kits use either standard Mikuni or Kehinin carb parts, which is nice if you want to deviate a bit from what the kit contains — you just go down to the shop and buy a $5 jet of a different number. Dynojet uses its own numbering system to prevent knowledge piracy, and it can be a bother to swap jets back out by mail with Dynojet if you want something slightly different. However, my limited experience with two Dynojet kits for non-Triumphs shows that they were right on as directed.

Do-it-yourself: This way is cheaper, but involves a bit more work. On a U.S. bike, you can track down the European specs and just bring it up to euro standards, with usually a small but significant gain in streetabliity, and especially in cold starting. The trouble is tracking down the jet numbers. Luckily, that’s what’s in this FAQ. Or, you can find someone else who has done mods to your exact same bike and transfer the results over. There’s a bit of that in this FAQ as well. On the Hinkley 98 hp engines, this can be done as cheaply as about $10, with all mods being reversible. I’ve gotten $5 genuine Mikuni jets from Dennis Kirk, a U.S. mail-order company. A dealer should be able to get them for you as well.

back to top A quick review and horsepower poententials
It is confusing that there are so many different ways of tuning it up. What should I do?

This is, of course, up to you. You need to decide what you want your bike to do. If on the track, go for full on jet kits. If on the street, maybe simpler measures might be worthwhile.

Here’s an great overview from John Fitzwater

Suggested mods: (these apply to full house “Daytona spec” 900 engines)

SuggestionPotential gains
Adjust the stock jetting as per FAQ very cheap, very effective3-5bhp midrange gain, little up top.
Dynojet kit (expensive considÕg small gain, but a necessary evil.)3-5bhp midrange gain, little up top.
Mild intake port work. Best mod if youÕre serious, get it done at major service time.8-10bhp on top on stock, BIG midrange jump.
Planing head, inc. comp. ratio. Time consuming, small gain for a lot of work, but worth it.No real gains up top, but excellent low and mid-range stomp. Aggressive.
Fit 3/1 Micron/Sebring/Staintune all are expensive, but the sound and improved accelleration is worth real hp gain, but great increase in power-to-weight ratio. (see section on pipes)
Lilley chipDont bother
Sims and Rohm adjustable timing rotorThe juryÕs still out: only beneficial if your fuel is crap and needs more burn time (see Jim BazzÕ experience on his Daytona 1200. He is not very big on the timing rotor at all.)
back to top Wow, just how much horsepower is in those triples?
From John Fitzwater

Just quickly, we have managed to coax an almost stock S/T up to 102bhp (rear wheel) at 8900rpm. It is still fitted with stock mufflers, though it has a Dynojet kit fitted, and a slighlty modified airbox. We have discovered there are two types of Dynojet kit (early and late?). The “early” one can be distinguished by a double diameter needle, while the “later” type is a conventional needle. From our tests, the early type seems to give better bottom/midrange, the later better top end. Both fill in the funny downward blip (a Triumph 900 triple characteristic) in the power curve at 4800rpm. Removing the intake baffles when fitted with a Dynojet kit will increase power; however, removing the intake horns will knock the the top end off in some cases (though it does give a nice increase in midrange), so we often leave these still fitted.

The Manager of the Spares Division of our Triumph Distributor here in NZ has a hotted up S/T – he’s claiming a rear wheel power output of 120bhp and is running the following gear:

  • Keihin 40mm flatslides (NZD2500)
  • Flowed heads (they were already very good NZD800)
  • Super Three cams (NZD1000)
  • Lilley 3/1 (NZD750)
  • Lilley chip (NZD700)
  • Planed head

Its easy to get 5-7bhp out of these engines – more than 10 will cost you.

From Norm Bartoo:

I don’t have any dyno info first hand. However, the Speed 3 challenge has set 102 or 105 hp at the rear wheel as the upper limit (they test the bikes after a race, at the track).

back to top The Standard Disclaimer
What you do with your bike in the privacy of your own garage or tuning shop is between you and your beloved bike. This inform- ation, while compiled from actual experiences by those who have been this way before, is inherently confusing. Tuning is a sticky business. In a nutshell, we’re not responsible if something doesn’t work. If your bike blows up, don’t come crying to us. ;-)

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6.1.2. Jetting

back to top Summary of jetting experiences
Here’s a chart of main jets, needle position and mixture screw information compiled from people who have done changes at the wonderful place that is I am deeply indebted to the folks who actually did this work.

After the chart are detailed e-mail messages from each of the folks who were kind enough to help me out when I was searching for information. Later in this FAQ is my experience in making some of these mods that I thought made the most sense. A special thanks here to:

  • John Fitzwater, tuner extrordinare and Triumph dealer in Nelson, NZ, who has done dyno work on the triples and was gracious enough to share his info. If you’re ever in Nelson, look him up. I’ve got half a mind to travel there myself to do some business with him, for all the help he’s given folks on the list (
  • Norm Bartoo, whose added a Sebring 3–>1 pipe to his once-Calif.-spec Speed Triple and reports good results with the pipe and rejetting, including easy 1st- and 2nd-gear wheelies (
  • Carlo Klein, who bought his Daytona 1000 with a few miles on the clock and later discoverd it had been Dynojet-kitted, and tracked down the original specs ( He’s now taking the next step by having a tuner fine-tune it.
  • Leon Watts, who rides a ’94 Daytona 900, and was kind enough to forward on the European specs (
  • Jorge Glascock , without whom none of us would have ever exchanged information. Jorge ran the original triumph mailing list. Net Triumph riders everywhere owe Jorge a debt of gratitude
  • Steve Manes, who stepped in big-time to keep the list from folding when Jorge had to move on. Running a mailing list is often a thankless jobs, so: THANKS!

The list is by no means complete, and I’m very interested in any adds or corrections folks might have. Please e-mail Grant Parsons at with any information you might care to add. Or better yet, subscribe to the triumph mailing list and post stuff there. See below for information about the list.

             Main Jet
            (Cylinder)     Needle Position
           1    2    3   | (Needle number)  | Mixture Screw | Pilots From
Stock  | 125 | 120 | 125 | 4th groove f/top |~1 percent CO  | 40 | T’umph USA    | | | | | (~1 turns out)| | USA
Stock  | 125 | 120 | 125 | 4th groove f/top |3-5 percent CO | ?? | Leon Euro     | | | | 5E56 |(2-3 turns out)| | 
Inside | 125 | 120 | 125 | 4th groove f/top | 3 percent CO  | ?? | A good track *| | | | 5E56 |(2.5-3 turns | |source+ 
THE Hot| 130 | 125 | 130 | 5th groove f/top | 3 percent CO  | ?? | John setup    | | | | w/2 spacers 5E56 |(2.5-3 turns) | | 
Stock  | 125 | 120 | 125 | 4th groove f/top | ?? percent CO | ?? | John NZ       | | | | 5E56 | (1.5turns out)| | 
Norm’s |127.5| 125 |127.5| 5th groove f/top | 3 percent CO  | 40 | Norm Sebring  | | | | | (??turns out) | | 

back to top Any thoughts on Dynojet kits and Triumph triple engines?
From tuner and dealer extrodinaire John Fitzwater :

Depending on the state of tune of the bike in question (eg slip ons, 3 into 1 etc) we will either fit a Dynojet kit (for non stock bikes) or rework the factory jetting in the case of stock bikes (stock airbox and mufflers)

In NZ the 90bhp motors (Daytona,Sprint,S/Triple etc) are fitted with 120 mainjets on the centre cyl, and 125 on the two outer cyls. The needles are 5E56. The clip is in the 4th groove from the top.

(The Dynojet kit) contains a drill for the slide, and a drill for the air jet (I think). Likewise, I think it came with springs (pardon my lousy menmory – I only own the place – the mechanics do the majority of the dynotesting and kit fitting). The mixture screws shouldn’t need fiddling with according to Dynojet, and we’ve found this to be true.

(Anything particularly troublesome about the install?) The worst part is the time required to removebattery/seat/panels/aircleaner/ coils/carbs and fuel and breather lines and then refit the whole mess.

We were disappointed with the Dynojet kit on a stock bike, but it is a must on a modified bike, cos you just can’t get the stock jetting rich enough.

From Jim Bazz

Interesting news regarding the Dynojet kits – per two different sources (one of the engine builders at Sims & Rohm and Matt @ Luftmeister/SouthBay Triumph) the kits are too rich!

Sims & Rohm had just received a Triumph with the kit installed from Corbin. Said it was way too rich and needed a lot of dial in work. Matt@Luftmeister also said the kit was way too rich and after you’ve drilled out the slides, you’re basically screwed… Luftmeister is working on their own jet kit which they will test on their dyno and CO tester – but this will be special tuned for the pipes they are producing…. More complications!!!!

back to top What about Dynojet kits on the fours?
From (I seem to have lost the source; if it was you, e-mail for credit.)

Dynojets kit – part # 5101.001 – consists of the following parts: main jets (2 sizes), fuel needles, emusion tubes, washers, e-clips, and slide drill bit (size #40). This kit retails for 165.00 US.

The main jets supplied are DJ112 for stock exhausts and DJ 116 for use with aftermarket headers or high flowing baffles. Regarding the mixture screws, Dynojet includes a 5/32 bit to drill out the plugs and recommends seating the screw and then backing out approx. 2 -1/2 turns. The instructions also call for installing the Dynojet needles on groove #3 using all of the stock spacers and locating the Dynojet washer above the e-clip.

Dyno chart shows the stock bike pulling about 116 HP at the wheel with no appreciable dips in the powerband. With the kit installed and still maintaining the stock airbox and exhaust, the bike now pulls just over 130HP. Power curve parallels the stock bike for the most part – there were no inherent dips to overcome. (This is four a four, folks, so stop salivating).

back to top What about just massaging the jets and not going for the expense (and drilling) that a jet kit requires?
This, also from John, is golden information, a veritible Holy Grail for do-it-yourselfers. (It is the ‘HOT SETUP” above.) Thanks John!

FWIW, on a stock bike, you can get very good results by reworking the stock jetting.

Triumphs triples have a characteristic downward bilp in the power curve at 4800 rpm. You can fill this in by lifting the needle to the 5th groove from the top (ie bottom groove) and fitting a couple of Dynojet style needle shims under the clip. This will give you about 4.5bhp increase at 4800rpm by filling in the hollow.

(Air mixture screws should be turned to between 2.5-3 turns out, or, more specifically, 3 percent co, measured using an exhaust gas analyzer tied into the header.)

We take the centre mains out to 125 and the outer cyls to 130 – this will give you about 1.5bhp at 8-9500 rpm. The good bit is it costs you almost nothing other than time.

back to top What if i just want to spruce up the power band with even less work and eliminate the cold-starting problem we’ve got here in the U.S. without seriously mucking about?
This is the information on the “Inside Track” specification.

Let’s just say this came from a source very close to Triumph and leave it at that, since messing with jets is an EPA-mandated no-no and could not be endorsed in any official capacity whatsoever. Not that I’m saying this is any way official at all. Even if this information happened to come from within Triumph USA. Am I waffling enough on the source? I thought so :-)

My source says the jetting in the U.S. is identical to the jetting in Europefor the 49-state models. The only difference is in the mixture screw. The source suggested not messing with the jets at all and adjusting the mixture with an EGA machine, or an Exhaust Gas Analyzer. U.S. models are set at 1 percent CO, and they should be reset to 3 percent CO. Better shops have EGA machines, but they’re awfully expensive for home mechanics. Such changes may require drilling and removing the metal covers over the air mixture screws, and would, for the record, be illegal (as would *any* carb mods, for that matter, but I assume you’re running this bike on the track, right? ;-)

If you donUt have an EGA (the things cost like $2k for a good one), I’ve had four separate and knowlegeable sources confirm that 3 percent CO is about 2.5-3 turns out.

Doing this, the source said, would eliminate the cold starting problem and generally make life grand. It would also set the carbs up to euro spec, according to the source.

The source offered that the Triumph shop in Lynchburg, Va., USA, has done a fair amount of dyno testing. It seems as if they might be a good source of info, fwiw.

If you don’t have access to an EGA, take this advice from Pete Serrino :

For those who don’t have easy access to a CO meter you should be able to get “close enough” ™ with a Colortune. The difference between US and Euro Spec is probably about 1/2 turn on the mixture screw. This is well within the resolution of a Colortune given a little practice. For those who are unfamiliar, a Colortune replaces the sparkplug and allows you to view the color of combustion. Adjusting the mixture is analagous to adjusting an acetylene welding torch. These work best for setting idle mixtures. They are much less useful for setting needle positions and can not be used for main jet tuning. About $35US.

Too rich a mixture and it burns orange, too lean it becomes blue/white. Ideal mixture is a medium blue. I have found on most of my bikes that adjusting the idle screw so the orange just diasppears gives the best results, ie. no hesitation off idle and smoothest running. This probably correlates to something above 3% CO. I don’t know since I have not checked with a CO meter.

If you have ever adjusted the screws using the highest idle method you may have noticed typically there is a region about 1/8-1/4 turn wide where the idle speed doesn’t change from max. This is where I set it at the richer end maybe 1/16 of a turn (1-2 screwdriver widths) from the point where the orange disappears.

So, starting with FAQ 3.0, you began recommending 2.5 turns out instead of 3 for the air screws. what gives?

I’m following what I’ve learned after some tests, and going by what John Fitzwater recommends. I (Grant) said:

i should add that after some initial testing on an ega, the “three turns out” recommended in the jetting faq may be a bit on the rich side. unfortunately, since the machine my shop had measured only at the muffler, and not the triumph-recommended header tie-ins, i can’t say by how much.

the bottom line when setting the CO level is to use an ega that ties into the header. i’m afraid there’s no way to give a blanket recommendation for air screw settings that will result in 3 percent, at least until i find a shop that can do it through the headers. mine are now set at maybe 2.5 turns out, but i can’t say whether that’s optimimum or not. it’s still much better on the cold start than the restricted 1-plus turns out that us epa regs require, and i’ll leave them there until i find the proper ega.

To which John Fitzwater replied:

I’ve been thinking myself that three turns sounds a lot, so I just called my Service Mgr to confirm. He sez we check the EGA readings at the header, and that most bikes require 2.5-3 turns (ie nearly all the way out). This indicates that in reality, the low speed fuel jet is too small, but as no other problems seem to develop, it’s probably best left alone. He comments that Thunderbirds especially require 3 full turns, though bear in mind, there are individual differences in indiv bikes (which is why the screw is adjustable in the first place!).

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6.1.3. Airbox/Carburation

back to top Are the airbox baffles superflouous? Shouldn’t I just take them out to let the engine breathe better?
More from John Fitzwater (

You may have read various experts telling you to remove the air intake extensions and the noise absorption baffles…. Our dyno says leave them in. Unless you have a Dynojet kit that allows you to dramatically richen the midrange, you’ll lose heaps everywhere.

back to top How about adding separate ‘pod’ filters instead of the airbox?
From Richard van Laar (

Separate filters tend to work better in the upper rev range and peak power. I can’t say how much because it’s different on every bike, look for something between 1 and 4 bhp. The replacement filter in the airbox works throughout the range, expect something like 2-3 bhp. In some cases removing the side mufflers and boxes with a K&N works good too. You’ll have to try on the dyno, the results are different on a naked Trident and a fully faired Daytona.

Keep in mind that separate filters are extremely noisy, especially for the driver. Looks good though.

back to top Know anything about how flatside carbs might work on the triples?
Richard van Laar ( does:

Slide carbs on a triple look great but they make the bike A LOT less user friendly. On our dyno we see a lot of bike which had a carb-swap with slides. Never a triple up till now but the results are always more or less the same. Some bikes gain top end but often loose midrange.

Slides work best on a tuned bike (hot cams, ported heads, big-bore etc.). In other words, a bike that flows a lot more air. One important thing is ALWAYS the same:

Wack the throttle open to early, to fast or at the wrong moment and the carburation will stumble BIG TIME. The engine will drop into a power-dip the size of the Grand Canyon. Slide carbs don’t have the self-regulating behaviour of a CV carb (stock on Truimphs).

When you wack the throttle on a stock bike the butterfly valves open quick but the vacuum-slides open a lot slower depending on the increase in air velocity. A CV carb opens almost at the same rate as the engine can swallow more air. When you do the same with a slide carb the air/fuel stream will be slowed down suddenly causing the engine to stall and drop power and torque. Triumph triples are about midrange and torque. CV carbs are perfect for this.

There’s a lot to improve with Dynojet kits and stock carbs/air filter. Optimising slide speed and air/fuel mixture will greatly improve throttle response (fast and aggressive), power and torque and fuel economy. Difficult thing is it takes a very good and experienced dyno operator. It’s not something you can write down how to do it. Every bike is different.

If you do want to fit slides, GO FOR SMALL DIAMETER CARBS like 36 mm. A slide carb flows A LOT more air compared to a CV carb with the same diameter. The stock CV carbs are 36 mm. A 36 slide is equivalent to a 39 or 40 mm CV in flow capacity (approx.) Don’t forget this. Small diameter carbs have a higher air velocity and are better for midrange, torque and throttle response. Guess why Triumph fitted 36′s.

back to top Anyone have any experience with the K&N filter replacement?
Carlo Klein ( has:

I’ve just replaced the air filter by a K&N ‘free flowing’ filter (K&N #TB0002), to be dropped into the airbox. As the costs of the original Triumph foam filter and the K&N are comparable I thought it a good idea.

The K&N filter has the advantage that it can be cleaned whereas the original filter can’t be according the manual. I however tried that a few months ago, but am unsure about the beneficial effects it had.

The replacement of the airfilter is a PITA as I had to remove the rear luggage rack and bodywork and get the carbs out before I could get at the airbox. I hoped it would go as easy as I suggested earlier by taking the airbox apart and sliding out the filter sideways, but it just didn’t..

I can’t say yet whether it improved mileage, I hope to be able to say more after this weekend’s tuning session.

Now Richard suggested separate airfilters attached to the carbs, wouldn’t that upset the design as it’s intended with airbox? Any opinions? Note I’ve got the four cyl. engine which might behave slightly different from the triples.

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6.1.4. Exhaust

back to top What about the Sebring 3-into-1 pipe for the Triumphs?
Norm Bartoo (norm@wallyworld.UCSD.EDU), in California, fitted a Sebring 3-into-1 pipe to his Speed Triple and was very pleased. Here’s what he has to say about it:

The jets I ended up with are (for the sebring exhaust)

  • pilot = 40
  • main = 127.5 (1&3) 125 (2)
  • needle = raised 20 thou (1 clip position)
  • air screws set at 3ppm CO

Incidently, the final main and needle settings were suggested by someone at Triumph NA based on “average settings seen at speed Triple challenges. This jetting is good from sea level to about 3000-3500ft. Above 3500ft it begins to feel rich and at 5000 ft it IS rich (but still quick enough to stay with everyone else).

BTW, we tried CO levels all the way to 5 ppm (europe specs are 3-5ppm) & found best results at 3 ppm. I do not know what to use for a set of Micron slip-ons, but I don’tthink it need to be any more rich than mine.

Finally, gas milage dropped from 41 to 37 mpg and the bike was much more willing & comfortable to cruise at 3000 to 3500 rpm when not hurrying – good thing ’cause the Sebring pipe is loud (about 102 db at full throttle & 6000 rpm)

This has been tested (run hard) and is good from sea level to 3000 ft (it still runs good to 5000 ft), summer (as hot as 90 deg f) and winter (as low as 38 deg f) with relative humidity in the range of 10% to 86%). Plug checks show slightly more color than with the stock jets & pipes, but still whiteish grey (not tan) on Union 76 premimum gas (the oxygenated stuff) + 3 oz per gallon toluene (for throttle response & starting ease. Not really needed).

BTW, we put threaded inserts in the Sebring pipes like the stock ones, to use to set the CO. However, one bike was done by setting the CO (and jets) with the stock pipes, then putting onthe Sebring unit to save a few $’s. The Sebring pipes will polish up nicely (use a power wheel) has also used the Sebring. His impressions:

hey, i’ve got a 95 speed triple, with the sebring 3 into 1, drilled slides, and 130 mains, needle clip on richest setting, dyno’d at the 95 gnf at road atlanta, each bike must be dyno’d at end of race, the first leg of the speed triple challenge, trip nobles won, running on elf 111 leaded fuel, mine made 102 official hp, now thats a beast, mine has a very minute blurb right off idle, if i take off without enough throttle, i can live with it, and to the guy who lets f3′s stuff him in corners, ride it a little harder, it can handle it.

Another Sebring comment from John Fitzwater:

I have not heard any reports of the results of the Seebring 3-1 exhaust system alone, but combined with re-jetting, carb mods, and an increaded rev ceiling, you can increase the power output by as much as 10 HP. Then again, gains almost as high as this are reported with similar intake mods, aftermarket slip-ons or even the stock pipes, so it is hard to tell just what HP advantage the 3-1 system buys you. In any case, this extra power only becomes available at higher revs. Unless you are going to take the time to really tweak the engine, I think the primary benefits of the 3-1 system are reduced weight, increased ground clearance, and an improved exhaust note.

We recently fitted what Micron USA described as their last available 3/1 for a Daytona/Speed Triple. They claim Micron UK have ceased production of their existing 3/1 exhaust for Triumphs. The bike we fitted it to was the same Speed Triple we have been testing all along for thr past 9 months. Barring a planed head, mild porting, and a Dynojet kit, it was otherwise stock (eg exhaust/airfilter), and giving around 103-106 bhp rear wheel (depending upon fuel used).

Fitting the Micron (which is a great looking bit of gear) and then restesting confirmed what we have found in the past time and time again, no extra power was produced. In fact, there was a 1.5 bhp loss over the stock exhaust from 4500-5500 rpm, but otherwise, the curves overlaid one another. However……, as Peter has pointed out, the on-road performance gain comes from the reduced weight of the 3 into 1 – a staggering 11kg/25lb weight loss.

If you say you had 100bhp on a 210kg bike, you get 2.1kg/1bhp. With the Micron (or Sebring for that matter) fitted, you’ll have 100bhp/200kg – a 2/1 ratio. This weight loss will give you improved accelleration equivalent to upping your horsepower by 5bhp. On the road you can feel the much improved power to weight ratio ,and the bike acellerates like a startled gazelle.

And then there’s the sound….. (surprisingly we found the Micron very quiet however).

So when looking for more performance, you have to weigh up the cost effectiveness of weight reduction versus engine or intake work. What gives the best bang for the bucks? Then your emotions go and get in the way and say….”I gotta have than sound! Gimme gimme gimme!”

And a final tidbit from Richard van Laar (

We have tested and dynoed 4 triples (2 ST’s, one Trident and a Daytona) with this pipe and the results are very comparable. The power gain is substantial and not only at high revs.

With good carb settings (as always!) power and torque will improve throughout the midrange starting around 3.5/4 thou. Expect something around 2 – 5/7 HP steady building to the red-line. 10 HP is exceptional but possible. With a cut rev. limiter or a 750 igniter (11 thou limit) there’s more to be discovered. Besides this it improves ground clearance and reduces weight too. Both are “a bit” of a problem on a Triumph…..

I’m not writing this to convince others of my personal opinion. I’m running modified stock exhausts. I don’t like the looks and sound of the 3-1 pipe. It’s just our experience on the dyno. From a technical point of view IT’S GOOD!

back to top What about other exhaust systems?
The general concensus is that aftermarket exhaust systems will show little (if any) performance increase on the dyno. The advantages of aftermarket systems are reduced weight, increased ground clearance and an improved exhaust note.

See the section on exhaust systems in the aftermetket parts section for more information.

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6.1.5. Ignition

back to top How can I mess with my igniter to raise the rev limit?
Here’s the scoop from Richard van Laar (

On the new igniters you CAN’T cut the rev limiter!

If you plan to do anything nasty with your triple (tuning and stuff) you’ll HAVE TO cut the original rev limiter. Even on a near stock bike ith just a carb kit the difference is without question the best go-fast mod for the buck ($ 0,00.-)

All mod/kit/Dynojet enthusiasts (like myself) are raving about their bikes putting out 95 or 100 BHP at the rear wheel etc. but take a good look at the power curve of a triple. Max power is only available within a VERY SMALL rev range, in most cases 500 rpm or less.

There are two rev limiters in the original 900 black box. A 900 pulls the plug at 9700 rpm. Cutting this limiter(wire) moves it up to 11000 rpm ment for the short stroke 750/1000 engines. The 900 will be very happy with this extra headroom to play with and so will you.

With jet needle settings to match (with or without a Dynojet kit) max power will be available across a much wider rev range from 1500 to 2000 rpm.(eg. from 8500 till 10500 rpm)

In other words, all the available horses will stampede at least 3 or 4 times longer! Any idea how much faster your bike will be? A LOT !!

Specific instructions by Gus Schutgens (

Ok, WHICH wire is the one to be clipped and is this wire the same as on the 4 cylinder 1200 boxes? (Sorry to ask what is no doubt a retetitive question, but my email file cabinet was lost and I have NONE of our older posts).

In my case (a 95 daytona 900) it was a the blue loopback wire (draw back the rubber cover). I don’t know if it is the same, but how many loopback wires are there?

Does anyone know how the actual ignition curve compares to the 900/1200 Daytona ignition boxes? Is this a a viable swap (plug-in without further modifying the wire harnesses)? Any potential problems with this???

We compared some igniters on a dynojet and found no big differences. According to the experts there is no need for worries.

While I was on the dynojet we tried the new igniter. The old 900 ingniter with the rev limiter cut (=750 igniter) trough gave the best results. After that came the new 900 igniter (which can’t be altered), who gain some (very little) hp in the low/midrange, and lot ofcourse some in the top revs. The new 750 igniter (on my 900 daytona) didn’t had the gain in the low revs, and lost maybe .5 hp at some points. The changes for performance are not dramatic.

The final word from John Fitzwater:

We were told this mod was all the rage in Europe at the Service School, and shown what was being done. But of course, we would never condone such foolhardy actions. Ahem.

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6.1.6. California-spec Bikes

back to top How are the California-spec bikes different?
From Grant Parsons (

It appears that the California bikes (most of them, at least,) use the Tiger engine, although information on this has been spotty.

The California-spec model (of the Sprint, at least) has what a tech rep at Triumph USA termed “a different engine” than the 49-state models, meaning it has different cams and jetting and timing than the 49-state model. This engine is actually down several horsepower over the 49-state model on top, but is alleged to have more torque in the middle. Suffice it to say that if you’ve got a 49-state model, you might have to do more work to bring it up to spec than simple jets. ItUs unclear, too, whether a simple cam-swap would do the trick. The one thing that is certain is that air screws on the Cali engines are even leaner than the regular U.S. engines, which are leaner than euro-spec. ItUs a sure bet that tweaking the air screws to 3 percent CO would be a worthwhile mod to a Cali-spec bike.

It’s also safe to say that the fixes listed above may not work on California-spec bikes, and could, in theory at least, make them worse. If anyone has any specific information on fixes for the differently- specified cams on the California model, I’d love to hear it.

From Jim Collum (Jim_Collum@3mail.3Com.COM)

The Trident in CA has a Tiger engine (which means the softer cam) I was (reliably?) informed by more than one dealer and by Triumph in Georgia when I was trying to choose twixt Trident and ST. Hence less power output but usable lower down the rev range (and it feels that way, I have ridden one in the UK).

I understood that this was the only bike in the range materially different for CA. And therefore that the only difference on other bikes in the CA range from 49 state models was this timing/CO emmisions jigging ( apart from all that crap labeled ‘Honda’ under the rear mudguard/fender and its associated tubes to catch stray fumes), and while I’m on a roll the only difference twixt USA and Europe was that the front brake lines here cannot be braided metal (Eh! seems back to front doesn’t it, less for the USA) and that the headlight can be switched on or on (dont’cha love a choice)

From Graeme Harrison (

The CA-spec Tridents are equipped with the detuned 84bhp motor used by the Tiger. Both ’95 and ’96 models. Got the information from the local dealer here (Rod at Cal BMW-Triumph).

However, is it really an disadvantage given that the 84bhp mill produces massives amounts of mid-range torque (40% more at 4000rpms) compared to its 98bhp siblings? My understanding is that the Tiger-spec motor is built more for “real world” riding and offers more roll-on power than the 98bhp models. In addition, it is more focused on acceleration than top speed. Does anyone have a horsepower and torque chart one can use to compare the 84bhp and 98bhp triples?

From (source unknown)

Found out that the CA trump carbs also have a different diaphram piston (smaller size, slower lift…). I also read that the Tiger has a different ignition curve. The former can be cured by a jet kit, but I’m concerned about the latter (the igniter box is about $500.00). Am concerned that I may not get all the 49 state perf w/ cam and may need the 49 state igniter as well. Can anyone confirm this?

From (source unknown)

The CA model has only a single air intake horn (2 for 49er) and #105 mains (#115 for 49er) and the mixture screws completely closed. Has a slight hesitation in the lower gears whacking the gas on – leanness… The owner’s manual saze the CA model makes 78 HP at the crank as oppossed to 96 for the 49! That’s a big diff!

back to top

6.1.7. Tiger, Thunderbird, Adventurer

back to top What about modding the lower-hp/higher-torque Tiger, Thunderbird and Adventurers?
On Tigers, John Fitzwater says:

You can easily modify the stock mufflers to give a deeper, more resonant note. Takes about 1-2hrs, a dremel grrnder with cutting disc, a drill and drill bits and a handful of stainless rivets to do both. Cost is about $10.00.

Drill out the rivets around the rear cone bit, and pull the cone bit off. Drill 6-8 1/2 holes (or bigger if your drill can handle it) around the perimeter of the plate that you now see exposed. Take the dremel and cutting wheel, and the rear stainless cone. CAREFULLY use the cutting wheel to cut away the three welds that hold the end restrictor tube inside the outlet of the cone. If you are truly careful , you can do this very neatly. After you’ve cut away the welds, you can tap out the restrictor tube and its mounting plate. Then you can rivet the whole plot back on – it is difficult to find stainless rivets in exactly the right size here in NZ – out there in the real world you may find it no problem. The rivet behind the heat shield is hard to get in place without removing the heat shield, but if you hold your tongue right…..

After you do this mod, you will probably find that you need to richen up the low speed fueling just a little – maybe half a turn on the air screws or so. You’ll have to experiment a little. We fitted the ubiquitous Dynojet kit to ours and ended up with 85 bhp at the rear wheel (from 77 before) – it sure bounced off the rev limiter more easily. Fitting the Dj kit wasn’t easy as they dont make a kit for the Tigger yet, and we had to adapt a Daytona 900 kit.

John Fitzwater also reports that there’s more than just cam profile separating the T-bird/Adventurer engines from their higher-hp siblings.


I know the T-Bird has the mild “blue” cams to throw the torque curve low…

If one were to drop in the “green” cams (from Sprint, Trident), does HP rise to the level of the rest of the triples or do other mods have to be made? Is the cam profile the only thing separating output of a T-Bird’s mill from, say, a 97HP Trident?

Johnfitz answered:

You’ve got to address the lower compression also, plus the smaller intake rubbers. The airbox would also limit the breathing unless you were able to do something to improve it. Then you’d need to do something about the rpm limiter cutting in early…

You can get to 75bhp (rear wheel) quite easily by doing the mufflers (gut them or fit Sports options), intake rubbers, minor airbox mod’s, and minor jetting adjustments. This is about 10-12 rear wheel bhp down on the Trident, but it is nice and cheap, and wont put the bike “out of balance” (with respect to brakes, handling etc.)

None of the T’birds we’ve dollied up with mufflers and intake rubbers have needed major rejetting at all. If I recall correctly, we’ve only had to adjust the low speed mixture to prevent a gentle crackling from the zorsts on the overrun. Do not remove the intake baffles from the airbox or you’ll get a big ‘ole in the power at aboyt 3000rpm, just where you want it to take off from the traffic lights.

back to top

6.1.8. Personal experiences

back to top Grant Parsons (
Here’s what I did. I offer this as one person’s opinion. I like to think I got a good compromise between streetability and performance, but I have not dynochecked it. I can say, however, that it’s got a bit more punch in the midrange that is noticible, and the cold-starting problems have been totally eliminated. This is from two posts to Triumph@micrunity. Yes, I have a problem with uppercase letters. So sue me :-)

i finally took the time this week to mess with the triumph’s carbs. here’s the story:

to get to the carbs on this bike requires: removing the rear bodywork, removing the tank, removing way too many hoses (3 and one electrical connector) from the tank, removing at least one coil, and loosening part of the front faring on one side, disconnecting two cables (choke and throttle) and disengaging the block of three carbs from the engine and airbox after first half-way disassembling the airbox. (interestingly, the air intakes on this bike run down both sides of the rear subframe, and terminate to the rear of the rear footpegs). getting the carbs out took about 45 minutes; i’m sure that the next time i could do it in, say, 25, max.

the triumph engine is tall, and the huge, single-tube spine frame is even taller, so the area underneath the tank that often contains tons of airbox and electrical regulators, black boxes and stuff is not there. this means that everything that would normally be there is bolted to the rear subframe under the seat, making it a very busy place. without the bodywork, there is definitely an element of frankenbike to the rear section. i thought it looked kinda cool :-)

anyway, with the carbs off the bike, i took a carbide drill bit and wrapped tape around it about 3/8 of an inch from the tip. then i located the dork caps over the air screws on the underside of the carbs and drilled them out, after first covering all openings in the carbs with plastic bags and rubber bands. it struck me that condoms would have been perfect for that job. after drilling through them with a 5/32 bit, i screwed in a sheet-metal screw and pulled what was left of the caps out with vice grips on the screw.

after cleaning all bits of brass swarf from the carbs, i then recorded the positions of the screws.

no. 1 was 1 7/8 turns out.
no. 2 was 2 7/8 turns out.
no. 3 was 2 1/8 turns out.

this struck me as an odd range, but it *may* be because the mains are different in the middle carb. 125s on the outside, 120 on the middle. the jets are the same both here and europe. the only change in carb settings between here and there is the air screw. i’m interested in any reasons why the difference may be there between the cylinders of this bike. in talking to a friend about it, the best explanation we could come up with involved airflow to the carbs through the airbox.

based on advice from a tech at triumph usa, information in the shop manual, the most excellent john fitzwater, and a mechanic at forsythe motorsports, a great triumph dealer in winston-salem, nc., i reset the air screws to three turns out each. this corresponds roughly, they all agreed, to the euro-spec 3% CO (us emmissions require 1% CO, and therefore much cold-bloodedness on start-up). i still need to have this 3% setting fine-tuned with an ega; i’ll do that at the dealer soon. in any case, the caps would have had to come off before that could be done. (Since then, measurements with an EGA have shown 3 turns to be pretty rich; I scaled them back to about 2.5; see below.)

i then consulted the most excellent micro-faq on tuning and took john fitzwater’s advice from dyno-testing the 98 hpengines. on his advice, i took the needles out and moved the c-clip from the fourth-from-the-top position to the fifth-from the top position,raising them one notch. according to john, doing this and shimming the needles a bit this helps fill in a dip in the hp curve from about 4,800 to 6k rpm. at the fattest part of the dip, this supposedly gives you almost 4.5 hp in the mid-range.

i didn’t shim the needles, so presumably I’ve got something less than that. The main reason i didn’t shim the needles is that i didn’t want my gas consumption to go through the roof.

john’s hot set-up is then taking the mains up 5, from 125 to 130 on the outer cyls, and from 120 to 125 on the inners. i opted not to do this, as i don’t yet want to change the gas consumption yet, and i like to make carb changes gradually, so i can notice minute changes. i suspect i will do this at some point to see what happens, but not yet. i have full faith that if john says it adds a hp or two on top, that it does :-)

then i put everything back on the bike, leaving the rear bodywork off in case i had to pull the carbs again. it was getting late, but i put on the leather jacket, gloves and helmet for a test ride.

firing it up required choke for only the briefest of seconds, compared to maybe two minutes in the stock configurarion. this is because of the air screws.

on the test ride, the engine seemed to be running a bit heavy, and the cans smelled of excess gas. this confused me for a while, until i noticed that the revs were hovering about 1k at idle, when they should be at 1.25k or so. the only other times this happens is when the choke is not quite disengaged at the handlebar lever. i reached down and pushed in the choke at the carbs, and the revs came up to where they should be, and the gas smell from the cans disappeared.

upon closer inspection, i realized i had not routed the choke cable correctly. it was a tad kinked, and therefore was not fully disengaging. took the tank back off and carefully re-routed the cable. now the choke fully disengages.

on a second test ride, everything was grand. :-) :-) :-)

no cold-starting problems, and a noticable increase in mid-range. the bike also revs much freer in the lower part of the range. it’s odd, but this change makes the bike feel not only more responsive, but also, oddly, smaller — an admittedly subjective viewpoint. i have not ridden the bike much over widely varying conditions yet, but from initial tests, i’m very pleased with the results.

the price for more midrange and no cold-starting problems: a whopping $0. well worth my time, and every bit of it is reversible if i ever want to do anything crazy like, say, pass an emmissions test (not yet required in nc on bikes).

special thanks to all the folks i talked to before starting these mods, and especially to john fitzwater nz who helped me a whole bunch for absolutely nothing, and the folks on triumph@ who gave me their information for the micro-faq on jetting.


after riding a good 300 miles with my newly-reset carbs (see previous message), i can report that the mod was well worth my time. in fact, i’d rate it as the no. 1 mod that _any_ of the u.s. triumph riders should do. (international riders already have their cabs partially set this way from the factory).

before i relate the hard technical data relating to the way the bike rides now, i’ve got to get this off my chest:


now to quantify the differences.

there is _no_ cold starting problem at all. my starting drill now is this: key on, no choke at all, thumb starter and feed in throttle after one turn of engine. the engine lights instantly and can take throttle after only, like, one second, tops, even when cold. this is, imho, the way abike is supposed to fire, not the infernal cranking on full choke that epa leanness requires. this is the result of the air screws turned out 3turns, or more or less 3 percent CO. if you do nothing else to your bike’s carbs, i’d highly recommend doing this.

the bike revs much freer at the lower parts of the rev bands. this is difficult to describe. before, it used to rev like a twin, a bit slow on throttle response. now it revs more like a four: a small blip translates into instantaneous rpm rises. in practice, this means much easier upshifts and downshifts, and a lot more fun. :-)

also, there is a very nicely noticable hit in the midrange. john fitzwater reports a 4.5 hp increase in mid-range from moving the c-clip on the needles down one notch and shimming the needles (effectively raising the needles onenotch plus the shims). this translates into harder launches as the bike moves throughthe mid-range. i didn’t shim the needles, but even so, on WFO throttle, the hit is very noticable and _very_ nice.

overall, the bike just seems more responsive, and the barely noticable throttle lag of the stock carbs is totally missing. in fact, throttle inputs are so instantaneous that i actually _noticed_ that there was a lag in the stock carbs. the additional responsiveness, too, makes the bike feel a lot zippier, and in practice, a bit smaller and decidedly un-dreadnaught-like

i haven’t checked gas milage for more than one tankful, but if there is a difference, it’s only on the order of 2-3 miles per gallon less than before. there may, in fact, be no change at all, given that i lost a little gas from the tank during the removal and re-mounting of the tank.

all in all, a solved cold-starting problem and a noticable hit in the mid-range, all for a whopping $0

two thumbs up!

What did all this do to gas milage?

i was getting about 36 mpg before i messed with anything. i then took out the air screws and raised the needles one notch (leaving the jets the same — basically following european specs). gas consumption went to about 33.

eventually, i got to thinking that the three turns out recommended by triumph as a ballpark figure for the air screws was a bit rich, so i had it checked. the shop didn’t have the right adapters, but by checking in the pipes and not the headers, it seemed above the target 3 percent CO. i turned them back to about 2.5 turns until i could get to a shop with the right adapters to tie into the header, something i still haven’t done.

gas milage went up a bit, to maybe 35.

then, just to check, i put the needles back to their original position and found gas consumption went back up to about 40, real nice, and probably where they’ll stay. a slight increase in hp in the midrange, to me, probably isn’t worth dropping my gas range to less than twice my wife’s hawk. on a tour, that means i have to gas up with her, every 120 miles or so, so we don’t start doing leap-frog gas stops.

the bottom line i can draw from all this is that moving the air screws to 3 percent co on an ega (checked through the bolt-holes on the header and not by a ballpark figure of 3 turns) actually _improved_ gas milage, although the aforementioned valve job came in between the two measurements, so that might have had something to do with it as well. raising the needle seems to lose you maybe 3-4 mpg, by my totally unscientific testing.

back to top Jim Bazz
Dropped my Daytona 1200 off to have the first maintenance performed along with the installation of the stainless front lines, Pro Italia bar kit, Sims & Rohm adjustable ignition advancer and last but not least – DYNOJET’S CARB KIT!!!!

Spoke with the mechanic at the dealership and he said everything went well. Only “problem” was that the Mikuni’s on my Daytona have a different slide than the one in the illustration – mine only has one vent hole where the drawing shows two. So he got Dynojet on the phone and they walked him through it. Seems the drawing is a bit out of date… Regarding the snorkels and intake baffles, they said to leave them in – no gain in HP with their removal.

After speaking with Sims & Rohm, they said that the 1200 would *probably* be best with the timing advancer between 2 degrees retarded to 3 degrees advanced. They haven’t had one apart yet, but with the engine’s characteristics, they felt that was a good starting point. I had the piece installed at 2 degrees advanced.

Throttle response is on another level – quick doesn’t begin to describe it. It’s just plain snappy. After the wheels come in and are installed the mechanic’s going toroad test it a bit and fine tune it with his EGA.



Runs a LOT differently now. Starts up and idles much smoother and quicker. None of the previous cold bloodedness exibited. And these have been 35-40 degree nights the past two days.

To say it runs 100% better isn’t the start of it… Snappy throttle response, quicker warm ups, smoother and more even running idle – the works. With the Dynojet kit he backed out the mixture screws 3 1/2 turns which worked out to be a hair over 3.0% CO on the exhaust gas analyzer. Stock from the factory is usually between 1/2 – 1 %… really lean. Don’t know how much more power I have since I’ve only got 732 miles on it as of tonight and it hasn’t seen more than half throttle or 6000 RPM. By the time the Microns come in – 3 -4 weeks – I’ll have over 1000 miles on it (weather permitting) and will let her rip then. I’ll dyno run it after fine tuning the CO and ignition advancer and getting at least 2000 miles on it. Then, I’ll dyno it again at around 8000 miles. According to everyone I’ve spoken with – they develop their full power at around this age… We’ll see what happens! ;-)


Just had my beasty dyno tested this weekend at SPORTBIKE 96, a rally in Parry Sound, Ontario. My Daytona pulled 120 HP and 85 pounds of torque. They had also tested a stock 1200 and that one pulled 110 HP and 74 pounds of torque.

Best thing is that with the EGA hooked up while it was on the dyno, the dyno operator said my bike is damned near perfect – no need to further meddle with the mixture screws or main jets. Only advice he had for me was to shim the needles up 1/2 of a clip position, said that may further help the midrange. A full position would be too much, we’re “splitting hairs here” he commented. I’ll probably get over to my friend with the Dynojet 150 this week to establish a base line run here and then tinker with the advancer and snorkels and such and see if there are any free horses lurking around inside!

In another message Jim Bazz writes:

Just spent 3 hours on a Dynojet 150 tweaking my Daytona 1200 for the (hopefully) last time. Here’s what had been done : Dynojet kit installed as directed (DJ116 mainjet, E-clip in 3rd groove from the top) with CO set at 3% on an EGA, Sims & Rohm adjustable timing rotor, K&N filter in the stock airbox – baffles and snorkels in place and a pair of Micron slip-ons. The engine is also running on 94 octane “Premium” unleaded fuel.

This configuration yielded 11 peak HP over dead nuts stock at 9000 rpm and torque increased by 6 pounds up top with a huge gain coming right off the bottom at 2000 rpm – 6 HP and 5 pounds torque. Fine, all was well *except* for a flat spot/dip between 4500 – 5500 rpm. Tried jetting it out to no avail.

My tuner had been begging me to take out the adjustable advancer and reinstall the stock piece citing innumerous examples of bikes he’s set up (and dynoed) that were better off without any advance change.

Fine, just to silence him I bolted on the stock advancer. And the damned flat spot was completely smoothed out! Talk about eating crow! We had tried settings on that adjustable advancer from -2 degrees to + 7. No increased power anywhere – just the flat spot and a considerable increase in heat when set at + 5 to + 7 and no change of more than perhaps 1/2 HP at any rpm. the lines were simply tracing one another. To me it doens’t make any sense why the advancer would cause that flat spot so I bolted the Sims & Rohm piece again and the flat spot was back. The stock piece wins…

Next, I raised the e-clip to the second groove from the top (dropping the needle) to lean it out a bit. The result was an increase of 2 – 3 HP from 3500 rpm on up – parallel to the prior curve. End result – 125 HP at 9000 rpm and (my favorite part) 85 pounds of torque at a hair over 7000 rpm (tested at 720 feet above sea level, 86 degrees ambient temperature with a humidity level of 72%).

So all you 1200 owners out there save yourself some $$$ and leave the ignition alone.

back to top davet@valiant.CDS.TEK.COM
Just last week, I took my Sprint to my favorite independant shop (here in Denver, 5280′) for it’s 6000 mi. interval service, having found that the local dealer’s service department is completely useless. It had quite a bit of soot in the pipes, and the plugs were quite dark.

We went down one size on the main jets (125 to 120 ??) and lowered the needles one notch. We left the idle screws right where they were (others have reported good success by richening them slightly, but I don’t think it works at this altitude).

It really woke the bike up. It feels much livelier in the midrange, and the throttle response is much improved.

[ Ed note: He’s at 6,000 feet. These mods likely wouldn’t help at sea level!!]

back to top Richard van Laar (
Along with some minor mods the bike is turning out a healthy 102 HP at the rear wheel with a beautiful smooth power-curve without any hickups or dips. For those who are interested, this is the current setup of my 900 Speed Triple:

  • Slightly cleaned up intake ports, the cilinder-head was off anyway. I only took away some irregularities at the rubber intake manifolds at the point were they meet the cilinder-head. There were some small ridges.
  • New type 750 igniter with 11.000 rev limit.
  • K&N replacement filter in the stock airbox with these necessary adjust- ments:
    1. Dynojet 130 main jets for all three cil. (stock 125,120,125).
    2. Slide holes drilled from 0.8 to 2 mm.
    3. Stock needles in stock position (4th grove from top)
  • Modified stock exhausts. 30 mm hole drilled in the last chamber. Improves midrange (a bit), sound and top-end. Stock cans are too restrictive in the upper rev range (7500 up). They ‘fill-up’ with gas and choke the engine. It revs-out easier.
  • NGK DPR8EA spark plugs, one grade warmer than stock DPR9′s. These plugs stay cleaner than the stock plugs, especially on unleaded.

NOTE: Dynojet jets flow more fuel than Mikuni jets in THE SAME size. A Dynojet 130 jet flows the same amount of fuel as a Mikuni 132. This is caused by the camfered edges of the fuel holes in Dynojet jets, something to remember when you start fiddling with jets.


The bike is running a bit lean at the top-end. Main jet should be 132 or 134. Power will be in the 104 – 106 HP bracket with these jets. Not bad with the stock airbox and stuff. With separate K&N filters on each carb midrange power will improve further along with a bit top-end but I’ve not yet decided about the noise. The power-increase through the midrange is significant though. Look at the power-curves from Guz’s Daytona 900 on his web-page. His top-end gain is mostly a result of the cleaned up carburation, modified exhausts and 11.000 rev limit, like on my ST.

Further mods on my bike are:

  • EMS Race shock with heavier spring and separate compression & rebound.
  • 10 mm raised oil-level in stock forks.
  • Renthal alloy 42 rear sprocket (stock 43 tooth)

Within a couple of weeks:

  • Modified linkages at the rear shock. 15 mm longer connecting rods from the rear swingarm to the bottom of the shock. This will raise the back end of the bike 3 to 4 cm (approx. 1.5″) for improved ground clearance and sharper and faster steering.

back to top Carlo Klein (
[ Ed note: Carlo has a Daytona1000, which are not made anymore :-( ]

I’ve been tuning the bike over the weekend with the aid of a professional mechanic. The basic reasons were to improve mileage and throttle response and seem to have succeeded in both! I haven’t ridden enough yet to determine mileage but I should have been on reserve a long time ago as I write this :-)

Before I started the session I replaced the airfilter with a free flow filter from K&N (# TB0002). A Dynojet kit had previously been installed, and now I was able to record what the changes were with respect to standard (see below).

It is very important to check the carb float levels, as it will effect mileage immediately. Mine appeared to be completely off. You can either measure the fuel level or the float position in mm, but the easiest and practical way it to set the floats about parallel with the carb face. Make sure to hold the carb assembly almost vertical to minimise weight disturbance.

We checked the compression level, which was impressive: better than 13 bar for all cilinders!! (One of the features of the old model pistons :-)

After reassembly and replacing the spark plugs we measured the CO level at the exhausts which was completely off balance, and the bike was running way too rich. We drilled and threaded all the exhausts to allow for measurements per cilinder, the differences were up to 2%! We then set the individual CO levels between 2.7 and 3 %, while monitoring the carb balance. The sniffer holes were plugged with short 5mm allen bolts afterwards.

A previous discussion with the dutch Dynojet importer learned me that the stock Daytona 1000 mufflers were actually the best for power (least restricted), he had graphs to prove it. The kit should add about 10 bhp so I wasn’t really worried about power, but the throttle response has now improved considerably. We did not change any of the jets further, and I’m sure I didn’t create a flat spot as the improvement is from roll-off. I promise to do a Dynojet run and post the results..

Here are some specs;

Standard Daytona 1000

carburettor: Mikuni BST 36mm
venturi: 34.5
pilot jet: 40
pilot air jet: 1.45
main jet (1, 4): 117.5
main jet (2, 3): 120
needle jet: 0.8
needle (1, 4): 5E77-3
needle (2, 3): 5F95-3
choke jet: #45
float level from seam: 14.5 mm
fuel level from seam: 1.5 mm
float needle: NV Assy N 198008
air screw: 2 turns out

Tuned Daytona 1000

main jet (1..4): DJ 112
needle (1..4): Dynojet replacement
carb piston: hole drilled to 2.5 mm
air screw: set for 2.7..3.0 %CO
needle jet: Dynojet replacement
piston spring: can’t say if it is replaced??

A quick plug for a *very* helpful chap: Motorrad Krage, Krefeld (Germany), +49-2151-542523.

In another message, Carlo Klein writes:

I was tossing the idea of getting a Dynojet kit/tuning job for my Daytona 1000. Then when I cleaned the air filter and needed to take the carbs out, I decided to clean out the carb bowls as well. Just in case, I recorded the jet sizes. I saw the carb bowl screws had been replaced by allen bolts (or I would have done that myself!) so I suspected the carbs had been worked on before.

I then compared the recorded jet sizes with those stated in the manual, and finally got confirmation from the dealer who sold me the bike that indeed a Dynojet kit has been fitted!

This is what I copied from the shop’s manual (*not* stated in my own Service Manual, part no. 3850300, Issue 4 10/94):

   stock settings Daytona 1000
   jet (1, 4)      117.5
   jet (2, 3)      120
   main jet        1.0
   pilot jet       40
   pilot air jet   1.45
   needle jet      0-8
   needle (1, 4)   5E77-3
   needle (2, 3)   5F95-3
   pilot screw     1.5 turns out

I recorded: Dynojet Daytona 1000 jet (1..4) 112 (I believe this is a Dynojet-specific number and not comparable to the Mikuni jets above. -Grant) needles etc ????

Unfortunately I can’t compare its performance before and after the Dynojet kit. I have checked it’s power output (> 105 bhp @ 9,500 rpm – rear wheel) but that was on a pay-and-rev-it sort of bike fair, so I’d like to do that again properly and record the torque curve as well.

It has always been expensive on fuel (12 km/l), but then I thought I get a lot in return :-) The power range is *very* large, from 3000 rpm to redline (11,000) it pulls like a proverbial tractor. When I used it on the Assen track, keeping it between 7,000 and 11,000 rpm in 2nd, 3rd, 4th and sometimes 5th gear I was amazed by the power. I have tried the importer’s demo Super III once but was not too impressed by it’s power – only those brakes :-o

I almost never have starting problems, hot or cold.

back to top Rein Suyker (
About two weeks ago my Super III has had severall dynojet runs. They modified small parts of the bike and now I have 108 HP on my rearwheel and the rev. limiter will stop only after 10.500 rpm.

Modifications made:

  • Airbox replaced by three seperate KN filters.
    • sound has increased you hear the engine begging for air.
    • the middle cylinder now gets more air so runs more efficient.
    • drove with it through severall rain and thunderstorms -no problems.
  • replacement of the carberators fuel needles.
    • all three needles where not running smoothly they were all scratched on one side
    • clearence of needles has been improved. (according to the technicions more Triumphs suffers from this design-production mistake)
    • all three needles has been replaced with dynojet types.
  • replacemnent of the main jets
    • don’t ask for the type but they are bigger then the originals
  • drilled a hole in the silincer cans
    • an about two cm. diameter hole was drilled in the last chambre of the exhaust pipe
    • the sound is more deeper and a little but acceptable louder.
  • the airway in the slides is improved
    • the standard very small holes in the carb slides has been redilled with bigger diameter
  • changing the rpm limiter
    • a wire on the ignition box was cut so the rpm limiter is moved from already 9000 to more then 10.500 rpm


  • with every rpm the power and torque is improved
  • the max hp changed from 100 hp to 108 hp measured on the rear wheel.
  • the motor response on the throttle is more direct
    • if I turn the gascontrol you feel immidatly response from the engine
    • diadvantage is that when I open the throttle very quickly when running below 4000 rpm. the motor stocks (hiccups)
    • you also now really feel the power drop around 4000 rpm.
  • the fuel consumption is lower !
    • normally it was 1 liter for 12~13 km now it is 1 liter for 16 km.
  • the bike is more competitive.

In total it is a big difference compared with the standard setting

back to top Guss Schutgens (
Yes, I’ve given my bike a tuning session by ‘slowtec’ (what’s in a name ;-) .

Here some results.

What was:

Everything stock but;

  • K&N filters in airbox
  • rev limiter removed (up to 11.000)


  • 94 sae HP (range 8500-9300rpm) (on rear wheel)
  • 82nm torque (range 6100-7000rpm)


What is:

Everything stock but; (as far as they are willing to tell me ;-)

  • rev limiter removed (up to 11000)
  • Seperate K&N filters
  • Main jet 160
  • Standard needles (sorry, don’t know which groove)
  • 25mm hole in last exhaustdamper


  • 103 sae hp (range 9400-10000)
  • 100+ sea hp (range 8900-11000)
  • 84nm torque (range 6400-8200, nice wide range nah?)

Great response on the throttle! Also the ‘All Gear’ graph looks much better!! And a great sound! I realy like it when you drive at 5-6000 rpm and pull the throttle… bwoooaaaaap!!!!

back to top John Fitzwater (
We/I have been doing a lot of dyno testing on a stock Speed Triple for the past month, and have achieved some interesting results. The aim has been to see how much we can acheive out of a stock bike, and also to test the effectiveness of some of the aftemarket goodies available to Triumph owners. We will be printing the results of these tests in out soon to be released catalogue for Triumph owners.

Just quickly, we have managed to coax an almost stock S/T up to 102bhp (rear wheel) at 8900rpm. It is still fitted with stock mufflers, though it has a Dynojet kit fitted, and a slighlty modified airbox. We have discovered there are two types of Dynojet kit (early and late?). The “early” one can be distinguished by a double diameter needle, while the “later” type is a conventional needle. From our tests, the early type seems to give better bottom/midrange, the later better top end. Both fill in the funny downward blip (a Triumph 900 triple characteristic) in the power curve at 4800rpm.

Removing the intake baffles when fitted with a Dynojet kit will increase power, however removing the intake horns will knock the top end off in some cases (though it does give a nice increase in midrange), so we often leave these still fitted.

The ignition advancer by Sims and Rohm gave no measureable increase here in NZ where we still have leaded fuel of a reasonable quality – however, this may not be the case in other countries like the US, where slower burning unleaded fuels need more ignition advance. Very soon we lose leaded fuel here, so the advancer may have some application then.

The Lilley chip – hmmm. I’m unconvinced so far. Swapping between a stock igniter and Lilley chipped igniter shows no appreciable difference, barring a raised rpm limit, and even this doesn’t seem to be what it should be. (Lilley’s claim a limit raised to 10350 from 9700 – our dyno doesn’t think so!) I’ve asked Lilley’s for their comments (silence so far).

We haven’t managed to get hold of one of the elusive Dynojet/K&N air filter elements yet, but will be testing that soon, along with a 3 into 1 that we are building. On the subject of slip ons, there’s not a lot available here in NZ to try, however one of our customers has carefully disassembled his Daytona 900 mufflers and removed some of the internal baffling – it sounds beautiful – deep and mellow. They obviously are less restrictive than the stock muffler, though the dyno shows no measureable increase over stock mufflers. This leads me to think the mufflers are not the “plug” in the system , and I dont think spending a lot of loot on a pair of slip ons is going to yield big results (fashion aside!). I suspect the headers are a bit of a plug and we are going to try and modify a set of stock headers soon.

I’m itching to get into a bit of head work onone of 900s – I’m sure even a mild clean up would yield very good results – there’s some sharp old dags in the inlet.

Triumph have done their homework on this 900 engine. There’s no easy gains. To raise the power, you need to uprate everything that affects airflow and exhaust.

In a later message, John Fitzwater later adds:

If you are prepared to remove the head, and do a little combustion chamber and seat shaping work, you can get a power increase all the wat through the range, not just at peak rpm. We’ve just performed these mod’s to a couple of S/triples – 7bhp increase at 5000, maintained and increasing all the way up to a 105-5bhp peak at 9500, with stock exhaust, new igniter, stock airbox, stock air filter, a carb kit and ignition advancer. We do all this work for about NZ$1000 (USD$680) at major service time (when you’re half way in there already.) The result is a real grunter with a safe rpm limit. Lot’s of fun!

back to top Nigel Nicholson
I’ve made the following mods to my 95 T-Bird:

  • New airbox
  • Dynajet kit
  • Speed Triple intake manifolds
  • Competition exhausts
  • Steel brake lines
  • Corbin Gunfighter&Lady saddle
  • Leather panniers
  • Tank pads

Power is up to an estimated 72 hp at rear wheel (Dynometer run wasn’t “saved”). Bike now starts, goes, and brakes much better than before.

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6.1.9. Questions in search of answers

back to top Why do the stock jets use different needles while Dyno testing reveals all cylinders should use the same needles?
This one from Richard van Laar.

Fiddling with jets and needles on the Dyno there’s one I still can’t figure out.

With the much appreciated Dynojet kits all main jets are the same size. Triumph uses a smaller main jet in the middle cilinder, in my ST they were 125, 120 and 125. This makes perfect sense as the outer two cilinders are fed more efficiently than the inner one. Just take a good look at the stock airbox-system and you’ll see why. Also, the outer two exhausts are more or less strait through while the middle headerpipe is split in two. All in all the middle cilinder has a less efficient intake and exhaust and flows less air. Therefore it needs a smaller jet to get the same air/fuel mixture and maximum performance. So far this is all pretty logical in my opinion. Unlike most people think, temperature has not much to do with it. The middle cilinder doesn’t get any hotter than the other two (a tiny bit, not enough to need different settings).

Yet, everybody I talk to (Dyno-freaks mostly) is telling me to use the same jets in all three cilinders like Dynojet says. The strange thing is, a lot jap-multi’s have smaller jets in the middle cilinders too and again, Dynojet supplies the same size for all cilinders. Needles are identical too. Sure the manufacturers are not doing this for fun or meeting emission regs by leaning off just the middle slug(s) ????.


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6.2. Suspension modifications

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6.2.1. Front Suspension

back to top How can i firm up my Sprint’s (or other non-adjustable) stock forks?
Read Grant Parson’s personal experience with the Racetech springs.

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6.2.2. Rear Suspension
No information available.

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6.2.3. Tires
No information available.

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6.2.4. Personal experiences

back to top Grant Parsons (
I’ve tried springs from Racetech in the U.S., and they’re great. My experience:

after much hemming and hawing, i’ve finally installed new fork springs on my sprint. attentive readers may recall that i’ve been meaning to do this for some time, as i’ve had both the springs and these neat gizmos from race-tech that essentially revalve the forks sitting around the house now for about a month.

the race-tech parts, “cartridge emulators,” they are called, require removal of the damping rod, and then drilling several holes in it before reinstalling them. this makes the mod non-reversible, at least not without the liberal application of money. i’ve talked with folks who have installed these things on lots of bikes, and the emulators have gotten rave reviews in one of the moto-rags. but i’ve been a wimp about the whole thing, i must admit, because it’s non-reversible.

so this weekend i punted. i just installed the new stiffer springs and left the emulators in their nifty package. i’ll probably add them later, though i wouldn’t think they’d be required with the springs at all.

the springs, however, are wonderful. :-) they are race-tech single-rate (not progressive) springs of the .95 kg/cm (?) variety. i was worried that they would be too stiff, because they were not the tri-rate springs that came stock, and they are not progressive (either in action or in trademarked name). i had previously upped the oil from 10 wt. to 15 wt.

the springs are lighter than stock, and shorter. they required longer-than-stock spacers, of course. interestingly, in contrast to my usual anality when it comes to bikes, i wound up using a metal spacer in one side and a pvc pipe in the other. in theory, this would cause an imbalance, as the pipe would displace more air than the metal spacer, and the air compression would be different in each fork. i’ll probably replace the pipe one of these days, but i didn’t have the proper metal piece. what the heck — this isn’t rocket science.

anyway, after doing the usual car-jack-under-the-engine, three-point-balancing-act-from-hell, i put in the springs, and used the highly scientific method of setting pre-load. ignoring the formula in the instructions that involved complex measurements and two (count ‘em) two variables (the astute will notice that it would be impossible to determine either one of the variables in this case in any absolute terms; all you’d get would be an expression of one unknown in terms of the other), i just set the spring and the spacer in the tube and added an inch before cutting.

worked like a charm :-) static sag wound up being just at one inch (a coincidence i’m sure; it usually doesn’t work this way for me). fwiw, for anyone who adds these same springs and is wondering where to cut the spacers, i weigh about 185 pounds.

Empirically, the spring works much more like i prefer. the numbers

  full fork travel static sag travel under hard braking
old 6 inches 2.5 inches 5.5 inches
new 6 inches 1 inch 4 inches

subjectively, the front is tons better. the bike now point-and-shoots quite nicely. instead of the stock cornering drill ( brake, wait for chassis to settle, flick it over and gas it, wait for chassis to settle, correct line a tad as fork rake settles in), i now have a new cornering drill: brake, flick it in and gas it, rocket through corner as riding an exacto blade.

very nice. my worries about the straight-rate spring being harsher proved to be unfounded. it’s still plenty cush enough, even on freeway expansion joints, for all-day riding. it seems a tad rougher, but not so much that it detracts. and in any case, i gotta think the trade-off is well worth it. i can actually feel what the front is doing much better now.

the springs were $79 (and they are, as of now, the only american-available springs for the triumphs; surely progressive will make some soon; johnfitz has noted that maxxon makes a good spring in the uk). imho, well worth it.

the front works so nice, in fact, that i was able to back off the damping in the rear. also, either the new spring or the rear damping change has removed a slight headshake on trailing throttle at about 40 mph with no hands on the bar. can’t say i’m sorry to see it go. (though i do wonder where that wobble went to ;-)

now, if i could just work up the courage to drill holes in a damping rod that works darn near perfectly. i guess i’ll have to wait a while, let my standards come up to the level of the new spring, and then start bitching about how it doesn’t work as well as it could. or, i could just leave well enough alone. time will tell.

John Fitzwater also recommends putting an extra 50cc of oil in each leg if you don’t go whole hog on the springs.

To which I add:

this i haven’t tried, but i can attest to the beneficial effects of replacing the stock 15 wt. fork oil with 20 wt. it’s much better now, but still not perfect. it seems to me that stiffer oil than 20 wt. would damp too much without a stiffer spring.