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Proven Setups for Hinckley Classics - Carb Jets, Pipes, Airbox, Cams, etc.

192K views 203 replies 77 participants last post by  Rocbird 
#1 ·
The "what jets do I need?" posts are pretty common. The only hope the person has of getting a real answer is if someone who has had the same exact setup happens to reply to the post. That only puts them in the ballpark, but it's better than no information at all.

What these members are really looking for is a proven setup that works with the modifications they've made (or are thinking about making).

As much as I'd hate making it that easy for others after all the work I've put in (....copying Saigon5), I think we need a proven setups sticky (preferrably dyno-proven).

Alternatively, we could list what setups we've had that were at least rideable. That would be useful as far getting in the ballpark and identifying consistencies.

Or.....we could just club Jimmy900 and steal his records. :p


So what setups have worked (no major issues, explain the minor ones)?
 
#2 · (Edited)
Model: 2000 Adventurer (standard)

Carbs: Keihin CVK
Airbox: K&N in Trophy/Sprint filter box w/ 2x1.5" holes at bottom inlets.
No snorkels.
Pipes: Aftermarket (?) 3:1 with conical collector.
Manufacturer unknown, from 1998 Speed 3.
Muffler: DIY high flow.
Cams: Triumph 'blue' Sprint/Trophy
Ignitor: Stock 8,750 rpm

Setup T-43 (43rd setup since January 2007)

Main Jets: #130 Keihin
Needle: Factory Pro Titanium, clip on bottom notch
Float Height: 17.5mm
Pilot Jets: #38
Mixture Screws: ~ 2.5 turns
Slide port drilled to 3.0mm from stock 2.5mm

Butt Dyno Results:
Small throttle operation excellent. Smooth to 7000 rpm, no bucking or audible misfire. (#40 pilots caused misfire/weakness throughout range)

WOT -- Hot and Cold -- no misfires or bucking. (#125 mains caused misfire @ 4K rpm.)

Notes: Could feel thrust surges between 4-5 K and at approximately 6.5K indicating a lean mixture at 4K, rich mixture from 5K - 6.5K, and lean mixture over 6.5K rpm.

Thrust has substantially increased over the entire operating range and the zero to redline time in first gear has decreased substantially -- I estimate 1 to 2 seconds improvement.

A 0-60 mph test with my digital speedo read 3.5 seconds but that is unverified -- I need to check the speedo calibration with the GPS and verify the reading.

----------------------
UPDATE: The wire from the speedo sender unit came loose and dropped onto the ignition wires. That resulted in ignition pulses being added semi-randomly to the speed sensor pulses. That made my miles a lot shorter and my 0-60 time a lot less. I'll update again after I cal the speedo and verify it's accurate and consistent. Sorry 'bout that.
----------------------
UPDATE: Mileage: 10 Oct 07: I did a group ride last weekend with multiple gas stops and the mileage varied from 34 to 40 mpg (US) depending on riding conditions and speed. The multiple fuel stops were necessary due to a Sportster with a peanut tank.
----------------------
It's going to take a dyno run to see what the ultimate results of this configuration are.

Jim -- Senior AMD
 
#3 ·
Model: 1999 Thunderbird (standard)

Carbs: Keihin CVK
Airbox: K&N in standard filter box w/ 5 x 1.5" holes
Pipes: Stock
Muffler: TORs
Cams: Stock
Ignitor: Stock

Main Jets: #120 Keihin
Needle: 1 0.020" needle under stock needle
Float Height: 17.5mm
Pilot Jets: #40
Mixture Screws: ~ 2.5 turns
Plugs: DPR7EA-9

Butt Dyno Results:
Small throttle operation good. Smooth to 7000 rpm, no bucking or audible misfire.

WOT test:
Starting @ 2000 RPM in 2nd gear-then WOT. It stutters or bogs for an instant until about 2500-3000 RPM, then it takes off....yippee...until I hit the 6500 RPM pipe restriction spot that only slows it down a little. Doesn't appear to make much difference whether it is hot or cold for this test. But today was a cool day here...didn't even get to 60. This is not something I would do in normal riding anyway. I am almost always over 3000 RPM.

Future thoughts and questions:
If I put another shim or two under the stock needle I think it would help the accelleration @ 70MPH in high gear @ 4000 RPM??? If I put Thruxton needles in, would I need to shim them??? What RPM range do the shim affect? What RPM range does the difference in the tapers between the Thruxton needle and the stock needle affect?
 
#5 ·
WOT test:
Starting @ 2000 RPM in 2nd gear-then WOT. It stutters or bogs for an instant until about 2500-3000 RPM, then it takes off....yippee...until I hit the 6500 RPM pipe restriction spot that only slows it down a little. Doesn't appear to make much difference whether it is hot or cold for this test. But today was a cool day here...didn't even get to 60. This is not something I would do in normal riding anyway. I am almost always over 3000 RPM.

Future thoughts and questions:
If I put another shim or two under the stock needle I think it would help the accelleration @ 70MPH in high gear @ 4000 RPM??? If I put Thruxton needles in, would I need to shim them??? What RPM range do the shim affect? What RPM range does the difference in the tapers between the Thruxton needle and the stock needle affect?

The needles/needle jets supply a small amount of fuel at low rpms/small thottle from the straight section of the needles. The difference between needle straight diameter and needle jet inside diameter forms an annulus which is essentially a small orifice -- like a pilot or main jet. The velocity of the airflow determines how much fuel is 'drawn' into the airstream.

As the slide rises and the needle lifts, the tapered diameter of the needle starts interacting with the needle jet inside diameter and increases the area of the annulus which allows more fuel to be 'drawn' into the airstream. More lift on the slide means a decrease in needle diameter due to the taper and more fuel flows.

So.... If the slide isn't lifting enough or the needle taper starts too late (straight section too long) then you're going to experience a lean WOT mixture at low rpms.

At part throttle the lean operation can be masked (swamped) by oversize pilot jets and large mixture screw openings, but at WOT those options are essentially bypassed (due to low airflow velocity) and the needle taper effects become dominant.

The Thruxton needles are virtually identical in configuration to the FP needles with the clip on the bottom notch. In this configuration the needle head to taper distance is around 2mm shorter than the stock needles, so the tapers start acting with 2mm less slide lift than the stock needles -- much sooner.

I've found that it's the needle taper distance (from the head to the start of taper) that is critical to WOT operation in the 3000-4000 rpm range and that the effect is most pronounced at 4000 rpm with a modified air intake. Longer cams exacerbate the problem because the increased duration of the cam generates a lower velocity through the carb and doesn't open the slide as far -- spreading the cylinder fill over a greater time period means the cylinder doesn't have to fill as fast.

Shimming the needle effectively shortens the distance from the needle head to the start of the taper, but stacking 2mm of shims under the stock needle is not a good idea. The needle tends to 'wobble' more and will contact the needle jet and that may cause it to jam and bounce. Stuck or bouncing needles don't run well...;)

The Thruxton needles are less expensive than the FP needles, so that makes them worth a try, but be sure to check the pricing on both. With the value of the dollar down against the Euro, the FP needles might be a good value in terms of adjustability and price differential.

Shimming the Thruxton needles should be unnecessary. I tried a 0.5mm shim with the FPs and it was way too rich at low rpm to the point of misfire and bucking. When that didn't work I opened up the slide vacuum port from 2.5mm to 3.0mm. I don't recommend that except as a last resort with the bigger cams, but it is reversable with a judicious application of expoxy and re-drilling.

Does all this make sense? :D

Jim
 
#4 · (Edited)
Bike: 1996 Adventurer

Carbs: Keihin CVK
Airbox: K&N filter in stock box, one 1.5" extra hole right side (secondary box removed)
Exhaust: Thunderbike 3-1
Cams: Stock
Ignitor: Stock
Spark Plugs: NGK Iridium DPR9EIX-9

Main Jets: #115
Pilot Jets: #40
Needle: Stock with one shim (0.5mm)
Float Height: Stock (17.5mm)
Air/Idle Screws: ~2 turns out

Notes: (only butt dyno results)
- pulls harder than stock all rpm, especially low rpm torque is much better
- better throttle response (or only feels like it ?)
- pretty simple and mild setup, no heavily engine modifications
all in all, everything works really fine
 
#6 · (Edited)
Bike: 1999 Legend
Carbs: Keihin CVK

I've been through a bunch of set-ups (long-time AMD:D)... starting with the oldest:
August 2004
Mains: 120
Pilots: 40
Factory Pro needles 3rd clip
4x 1-1/2" holes in the airbox
Triumph 'Off-Road' Pipes

Max RWHP: 74.1*
View dyno chart

January 2007
Mains: 130
Pilots: 40
Factory Pro Needles 4th clip
Pod filters**
Custom 3-1 pipe

Max RWHP: 74.87
Max Torque: 51.96
First run with Pod filters replacing the modified airbox, and the new 3-1 custom pipe. Slight HP improvement, but look at the big lean spot at 4K
View dyno chart

June 2007
Mains: 130
Pilots: 40
Factory Pro Needles 5th clip (highest position)
Pod filters
T509 speed triple cams
Custom 3-1 pipe

Max RWHP: 86.98
Max Torque: 56.95
First try with the T509 cams. BIG top-end horsepower boost, but also a BIG lean spot at 4K RPM, leading to a BIG hole in the power band, and an actual HP decrease from previous between 5.5-6.5K RPM
View dyno chart

August 2007
Mains: 126
Pilots: 40
Factory Pro Needles 5th clip (highest position)
Pod filters
T509 speed triple cams
Custom 3-1 pipe

Max RWHP: 84.7
Max Torque: 55.63
This was where I had the bike professionally dyno-tuned. In addition to the jetting tweaks, the mechanic modifed the pipe to get better backpressure, which really helped the huge lean spot you can see at 4K RPM. He lengthened slightly one of the collector pipes, and added a small second baffle to another. Made a huge improvement in the way the bike runs. It still runs a bit lean at 4K, probably on account of the needles (see Jimmy's post above) but overall it feels great - no bogging, no stuttering, and major improvements in acceleration and top-end... feels much better on the highway now, almost like having a 6th gear :D
View dyno chart

HTH somebody...

*Note: all HP & Torque numbers are uncorrected... since I don't have the corrected #s for each run, figured I'd stick with an apples-to-apples comparison.

**Pod Filters... there are lots of opinions out there, I can only speak to my experience. I've never had any trouble with them in the rain, and I've ridden through some downpours (though I've never ridden them for more then 2-3 hours in the rain). I do have DIY carb brace (pics) and i wouldn't trust just the carb rubbers to keep everything together, personally. Jetting with them wasn't any harder then jetting for a drilled-out airbox. Others have had more issues, maybe I just got lucky. The filters I'm using are K&Ns with Jack Lilley aluminum adapters to attach them.
 
#7 · (Edited)
Great info Crosstie. :welldone:

Thanks for sharing it with us.


Here's my FINAL :eek: setup. No dyno, but I put about 700 miles on it this weekend and I'm completely satisfied with everything except the small throttle/low RPM operation.

Model: 2000 Thunderbird (standard)

Carbs: Keihin CVK
Airbox: K&N in stock airbox w/ almost the entire back hacked out (will add photo later)
Exhaust: Thunderbike 3 into 1
Cams: 955 Sprint
Ignitor: 95 Speed Triple, 9,700 redline IIRC
Advance: Factory Pro Ignition Advance Rotor +4 degrees

Main Jets: 140
Needle: Factory Pro, center notch
Float Height: 17.5mm
Pilot Jets: 40
Air/Idle Screws: 2 turns (plan on experimenting more when I buy the tool)

Notes: It was dyno'd a few days earlier at 84.6 rwhp with the following differences: 142.5 mains & needles on 4th notch down. With that setup, it was slightly rich across the board with a big, very rich spot at 5.5k.
 
#8 ·
I do not have a dyno run to post yet, but inspecting the plugs, and the thrill of the ride is enough proof for me, I have a 2001 Legend TT.

Keihin carbs:
128 Mains.
Stock Needles with one shim each.
38 Pilots @ 3.25 turns, got the 40's on the way, but idles fine, not much pop on decel.
Emgo pod filters.
Speed Triple rubbers, open.
Slip on aftermarket with baffle removed. Stock headers.

The intake note and exhaust note make music on WOT. Never heard a bike before or since like the triple opened up!

Poke
 
#9 ·
The latest set-up

Model: 1999 Thunderbird (standard)

Carbs: Keihin CVK
Airbox: K&N in standard filter box w/ 5 x 1.5" holes
Pipes: Stock
Muffler: TORs
Cams: Stock
Ignitor: Stock

Main Jets: #120 Keihin
Needle: Thruxton needles
Float Height: 17.5mm
Pilot Jets: #40
Mixture Screws: ~ 3.0 turns
Plugs: DPR7EA-9

Butt Dyno Results:
Small throttle operation good. Smooth to 7000 rpm, no bucking or audible misfire.

WOT test:
Better WOT operation with Thuxton needles at low and mid RPM. Thanks Jimmy!
 
#10 · (Edited)
Model 97 Thunderbird

1 Mikuni carbs taken off and replaced with Keihin CVK carbs off a 2001 model

2 Airbox in the bin - fitted pod filters S&B maxi-flow 125-RC-T conical (2.25x3.5x2x4) onto the Keihin CVK's. These are totally "free flow" and would give the same air flow as no filters at all. Air inlet (bellmouth) size is 57mm (CVK's only, Mikuni are different size)

3 Restrictive intake rubbers (with dimple) replaced with unrestricted (smooth) intake rubbers. The unrestricted rubbers should be standard with Keihin CVK carbs

4 Standard spark plugs changed for NGK Irirdium DPR8EIX-9

5 Main #98 jets replaced with #120 jets - This works perfectly the plugs are just the right colour (I live at sea level). Jimmy reckons it might be worth trying #125's but the risk is it might run rich at 5000 rpm to 7000 rpm

6 Copper washer under each carb needle - didnt seem to make any noticable difference but did it anyway. The needles on CVK carbs are not adjustable.

7 Mixture screw taken another full turn out

Everything else is stock ! Fuel is standard 95 RON.

Picture at:

http://www.triumphrat.net/hinckley-classic-triples/37399-120-mains.html

Im so pleased with the result I havnt bothered fiddling around anymore, The bike really smooths out at 4000 rpm to 5000 rpm and the iduction roar is fantastic bearing in mind the exhaust is standard. The economy as well as the power has noticably improved, I get about 20 more miles per tank. Recommended !
 
#11 ·
Model: 1996 Adventurer

Carbs: Mikuni
Airbox: K&N in stock airbox w/ 4 1.5" holes in the back
Exhaust: Thunderbike 3-into-1
Cams: Stock
Ignitor: Stock
Ignition Rotor: Factory Pro Ignition Rotor Advancer (+4 degrees)

Main Jets: 145
Needle: Dynojet, 2nd notch from the top
Float Height: 17.5mm
Pilot Jets: 40
Air/Idle Screws: 2.5 turns out

Notes: Haven't gotten around to the dyno yet, but pretty steady torque according to the butt dyno. It pulls so well now that I installed a 19T front sprocket. I was willing to trade a little torque for the lower revs on the highway. It's like adding a 6th gear.
This Winter, chucked the airbox altogether and went with K&N pods:

Model: 1996 Adventurer
Carbs: Mikuni
Airbox: K&N pods
Exhaust: Thunderbike 3-into-1
Cams: Stock
Ignitor: Stock
Ignition Rotor: Factory Pro Ignition Rotor Advancer (+4 degrees)
19T front sprocket

Main Jets: 155
Needle: Dynojet, 3rd notch from the top
Float Height: stock
Pilot Jets: 40
Air/Idle Screws: 2 3/8 turns out
 
#82 ·
Update April 3rd 2011.
This poor available fuel is creating issues with the tune on the bike. I think the stock pilots at 38 aren't enough, decel popping has gotten much worse. I'm going to fatten up to 40 or 42 PJs and back off the shim stack (3 now). Maybe move up with the MJ size and go 154-5...
I've got pods, epco pipes, 4 deg advance, stock cams and ignitor. I hope I can sort this out cheaply as I'm working on fcr carbs from a donorcycle on down the road. Trying to find the right gixer or Kawi for a donation... spending a grand on this bike is hard to do with too many other bikes needing tires and all the things they need. I'm too bike poor....
Anyone else had issues with enthanol fuel screwing up their bikes tune? Its really hacked up some older bikes my buds have... Damn alcohol belongs in bottles, not in tanks...
 
#15 ·
Proven Setups

Model: 1999 Adventurer

Carbs: CVK, no mods
Airbox: None- 3 K&N Pod/Filters
Exhaust: Stock, w/ baffles removed
Cams: Wilcox Engines.
Ignitor: Stock
Ignition Rotor: Stock

Coils & Spark Plug Wires: Nology

Main Jets: 120, FP
Needle: Stock, no change
Float Height: 17.5mm
Pilot Jets: 40, FP
Air/Idle Screws: 2.5 turns out

Seems to work....
 
#16 · (Edited)
Model: 1998 Tbird

Carbs: Mikunis
Airbox: Stock K&N Filter, air inlet 'foam silencer' removed
Intake rubber 'restrictor' reduced by est. 8-10% (area)
Exhaust: Thunderbike 3 - 1
Cams: Stock
Ignitor: Stock
Ignition Pick Up: Est. 2 deg advance filed from mount holes (rotor circumference ~ .65mm / degree

Coils: Nology

Main Jets: '98' dynojet
Needle: dynojet 3rd notch from top
Float Height: 14.0 mm
Pilot Jets: 40
Air/Idle Screws: 2.5 turns out

G/box sprocket 19 tooth

Great torque thru' whole rev range, pipes loud but great sound.

Now fitted unrestricted inlet rubbers T1240080 -
No jetting or needle changes needed, stronger in midrange than before, top end & low end as strong as before.
Torque curve feels strong, flat & smooth from ~ 1,500 rpm to redline.
 
#17 ·
Couple of things to add to my last post....

Checked my fuel economy also - 54 miles per gallon (Imp.) over 110 miles mix of slow mountain twisties & 100kmh (62mph) main roads.

Pleasantly surprised after reading test reports ~ 43mpg.

Clearly more power from improving air/exhaust flow can also mean good engine efficiency. (Probably 19t front sprocket also helps here - reccommend for 5 speeders where power mods done.)

Not sure if this fits here, but have just fitted Racetech Cartridge Emulators to forks. On Ireland's bumpy roads suspension matters, & as murphy's law has it, the worst bumps & potholes are on bends ! Cartridge emulators have made a massive improvement to brake dive & general front end control. I've kept the stock springs for now - I'm only 150lbs so no big deal. At $160 for parts (self fitted), for my weight & Ireland's roads these are easily best bang per buck of any mods I could make imho.
 
#18 ·
Hey Mike,

Did you change out the rubbers or remove some of the material on the inside of the rubber? Having Mikuni's, the unrestricted rubbers for the Keihens are not a fit. I was also told that Tiger's using Mikuni's had unrestricted rubbers but i cannot confirm. Let me know.
 
#19 ·
Patrol21

I started out working the restricted rubbers a bit, keeping well clear of the indents each side - maybe 8-10% area reduction. Then I checked out a few more posts & compared the fiches for TB & TBS.

TBS cams, airbox, igniter etc. all the same. Just different exhaust....& Keihin carbs with their unrestricted rubbers & same jets, needles etc as the later TB that had Keihin....+14bhp TB to TBS ?...some smoke & mirrors going on here methinks ;)

So figured I had to try those rubbers - they are from Mikuni carbed Tiger, I believe, part # T1240080

The results are excellent, midrange was good before tho' not as strong as low end & top end - now it's stonking torque right thru' :)

Interestingly, even tho' there was still a huge area difference between my 'worked' ones & the Tiger rubbers, no carb adjustments were needed.

I posted the full info. on the Proven Setups sticky.

It's quite possible the Dynojet parts don't make much difference & may not be worth the bucks. (My stock needles were worn tho') Very likely a 95 main jet, a notch or 2 richer on the needle, & 2 1/2 turn pilot screws will do the job....I would run that past the tech gurus here first tho'.

IMHO the .5 mm richer on the float heights is good for low revs high throttle pull.

Go for it :cool: !
 
#20 ·
Just realised I was already on the Proven Setups sticky :D

Couple of further thoughts....

That TBS exhaust seems to play a key role here over the TB, cos the airboxes are identical. Maybe it's to do with 'scavenging' - kind of turbo charging on the cheap one cylinder exhaust 'pulse' from a cross connected header can help to 'pull' the charge thru' another cylinder on it's intake stroke. I suspect the Thunderbike 3 into 1 maybe doing just that.

However, it may be that airbox mods can make up for this when using stock headers & TOR mufflers. Tho', as that rear airbox plenum is a 'tuned' resonant (air) circuit, the characteristics at different revs / throttle will be slightly different again...

All I can say is that my TB pulls like train with a 19t front sprocket (11% higher gearing) & still does 50+ (Imp) mpg - result :)

Thanks to all the posters who gave me the info to do it !
 
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#22 · (Edited)
Model: 1996 Thunderbird

Carbs: Mikuni
Airbox: K&N in stock airbox w/ 4 1.5 " holes
Exhaust: Yoshimura 3-1 for 96 Speed Triple
Cams: 96 Speed Triple (Green)
Ignitor: 96 Daytona Super III (9700 red line)

Main Jets: 120
Needle: Dynojet, center notch
Float Height: Standard
Pilot Jets: 40
Air/Idle Screws: 2 3/8 turns out
Iridium Plugs
Factory Pro 4 degree ignition advancer

Bike pulls hard throughout the range, slight flattening in the 4-5 range. Pulls real hard on the top end. Dyno'ed at 90 hp right after Yohsi install.
 
#23 ·
OK, the weather just got warm enough to pull the bike out of the shop and see where my mods stood.....ouch, Im used to hard reving and I have to change my timing.....I am hitting 7500-8000 RPM a ton faster......these bike are stangeled stock. Anyhow, IRLMike/Jimmy, Greg, thanks for the tips..here is what I ended up with

Air-K/N replacement (drilled some airbox holes but ended up too lean) taped them all up. Opening up the airbox is opening up pandora's box. If I have one piece of advise...leave it be or go with PODS (Jimmy's advice)
Mains-after much swiching around, I settled on the higher DYNOJET mains (came with kit)
Pilots-stock 40
Needles-DYNOJET on 3rd notch-made a huge differnce with throttle response
Pipes-removed TOR's and went with EMGO's. Can you hear me now?
Float height-14.5

Have not put on a dyno yet but the butt dyno leaves me tingling and my shift timing has to be much quicker........... But officer, I'm just getting used to the mods.
 
#25 ·
Patrol21

Cool :D

Brief mods to my set up so far:

Fitted Thunderbike 3-1 optional (& removable) 'DB Killer' baffle, cuts the noise down a bit especially at low revs, tho' still way louder than stock. Recommend

No jetting changes made, tho' only a brief trial as I've now changed over to stock Keihins. (Needle Jet/Slider wear gremlins :()
All ok & good power but will probably go for a Factory Pro needle kit, as I feel there's a little more 'umph' to be had at low/mid revs which I think the Dynojet needles on Miks did well.
 
#26 ·
Hi Mike,

The mods made a huge difference. I am not running my mains at the settings that I see listed on the forum....120's/130's....seems rich but I may go that route in time. Right now, I am estatic with the pull I am getting. I don't see a huge increase in top end but it gets there a ton quicker. I think going with the unrestricted rubbers made a huge difference..thanks for the part#'s off the old tigers. Anyhow, I have a good friend that I ride quite a bit with that has a Harley with about 4,000 invested in the motor to give it more umph.....we were nearly side by side thru the gears last year......I guess he'll be eating some Trumpet Dust this riding season..bon apetite..see ya!
 
#27 ·
Back to the Future

I did this:
http://www.triumphrat.net/hinckley-c...ighlight=t150v

Mains, 118
Pilots 40,
Thruxton needles.
I can get my airbox off in seconds, I can get my carbs off in under a minute.
Ridden it over 4,000km now and all over the rev range and in the rain and on +40'C days and had no problems. Definitely more power, and very smooth, plus it cut my 'back off pops' down heaps.

I'll get it dyno'd one day, but I was just happy to junk that cracked plastic wash basin they call an airbox for some steel!!!!
 
#28 ·
I tried using part #T1240080 @ my local Triumph dealer and they couldn't pull anything up with it. Is that number specific for an outside company and not an oem #? What year Tiger for the Mikuni unrestricted rubber inlets? I want them, I need them, I've got to have them! Optimum performance please!
 
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