Carb Jetting Survey For CVK Carbs

These are the results of the various jetting surveys from the bonnevilleamerica.com site.

Results are for the Triumph Bonneville America / America / Speedmaster ONLY!
Stock Pipes | Triumph Short Off Road | Triumph Long Off Road| Sceptre Longs | Sceptre Shorts | Bub Dresser Dogs | Raask Dragpipes

Triumph Stock Long Pipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
NA 120 42 In Stock, Paper All In
~2½
None Stock Setup
600 ft. 130 42 Out UniFilter Stock
None Tom's setup
Pipes are drilled out stock. Runs strong, No popping, No missing
5400 ft. 120 42 In Stock, Paper All removed
None? Renagade's setup
Baffles removed
Unknown 140 42 Out Unifilter Stock
3
None Johann's setup
Cleaned out with Raask baffles
Unknown 145 45 Out Unifilter All removed
1 Ampz's setup
Baffles partly removed
Unknown 130 45 Out Unifilter Top snorkle out
None counselor's setup
Tried 140's, stepped back.
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Triumph Short Off-Road Pipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
Sea Level 130 42 Out Unifilter All In
None Davydd's setup
Runs great - nice and smooth, much increase in perf. next to no popping.
Sea Level 130 42 Out Unifilter No Top snorkle
2½-3 (not enough)
None Matt's setup
35m 130 42 Out Unifilter All In
3 5/8
None Dave's setup
500-4500 128 (May go to 130) 45 Out Unifilter All In
None Shakey's setup
The increase in main jet size is just a thought for the time being. My mechanic seems to think everything is just about right as is.
600 ft. 130 42 Out Unifilter No Top snorkle
None dinqua's setup
Runs Strong, no popping, no missing, good idle, 45's and shims were too rich and poor idle, removed and idles perfect
2000 ft. 132 45 Out Unifilter All removed
2 SalMaglie's setup
One comment though about the 45 pilots with 2 shims. Although my Triumph dealer's shop doesn't have a dyno, they do have an emmisions testing machine and that's what they use to determine Air/fuel ratio and that's why they go with 45 and two shims. Or at least that's what the mechanic said. The bike runs strong in the 5,000+ rpm range when I really get on it off the line. In 3rd-5th gears I can really notice the benefit of the freer flowing air system, and the increase in jet sizes from stock. However, I still think it could run better in the 2,000-4,500 rpm range/1st-3rd gears. Maybe switching back to the stock pilot setup would help with this, I don't know.
4000 ft. 135 45 Out K&N RC2890/2900 No air box
2 (1.0mm) FriarJohn's setup
May need to turn pilot screw out some more
Unknown 135 42 Out Unifilter No Top snorkle
None dhaiken's setup
2nd version Tr. Shorties
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Triumph Long Off-Road Pipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
Sea Level 128 42 Out Unknown All removed
None Duece's setup
Pipes are the early quiet ones, The bike rips!
Sea Level 125 42 Out Stock, Paper Blew up with backfire, patched up, stock
None Barrow's setup
600 ft. 132 45 Out Unifilter All Removed
3-3½
1 (0.05mm) tinman's setup
Might change screw setting when warmer. Now the red BA just got faster!
Unknown 142.5 42 In for now Unifilter All in
3
None DK's setup
Dealer did mods, Found carbs not sync'd, AI going soon.
Sea Level 137.5 42 Out Stock, Paper All Removed
3
0.5mm Tadpole's setup
Floats set at 17mm exactly. Carbs synchronised exactly and idle now reset to 1000 rpm when fully warmed. I use 98 octane premium unleaded fuel at all times. I only use 1/2 choke and we are getting colder weather here, not as cold as you get though. About 38/40f and i don't touch the throttle and it starts fine. My fuel economy is nearly the same as stock and I probably ride it harder than average, its giving me 19kms per litre or 52/53 mpg (imperial gallon not us) Mufflers are made for Triumph Australia part #T0060 Hope the info is of help to others, I have put a lot of time and testing into getting to this set up, so much so that my dealer is using it to set up bikes with the same mufflers. I have proven the settings also by using a vacuum gauge and a colourtune sparkplug which shows the colour of the fuel burning.
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Sceptre Long Pipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
3500 ft. 122 45 Out Stock, Paper Stock
2½ (Probably go to 3)
None SpeedyBrit's setup
Pulls stronger between 6-8000.(Middle seems similar to before). Makes kids cry, pets run for cover, Harley dudes just stare!!
Unknown 122 45 Out Stock, Paper Unknown
None INNIS's setup
Unknown 122 48 (New Number) Out Stock, Paper Unknown
None Charlie Griffin's setup
tried 130, 45 (old number?), 3.5 out with Uni-filter, one shim. Ran, but rich all over, top end was strong, big popping. Decided to follow Team Triumph's info with 122, 48 (new number), 1.75 out. I stayed with the Uni, Team T. says stick with stock air cleaner, top air intake removed, snorkels still in. This seems to be the ticket, no popping all smooth and nice power. I'll try this set up for now, Team Triumph said they are testing new needles and to keep checking their site, they seem to have a different approach than going with the big jets. Maybe later I'll try the high H.P. set up mentioned on the BA web site. I have no idea what I'm getting-no dyno check. I just know it's the best power-- so far.
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Sceptre Short Pipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
600 ft. 130 42 Out Stock, Paper Unknown
None jaymo54's setup
The bike pulls like a raped ape now (went from 125 to 130 mains) I can’t believe swapping the mains made that much difference. Runs so much more effortlessly at highway speeds between 75~90 mph - very smooth.
1150 ft. 130 42 Out Stock, Paper All In
3
None LarryShep's setup
Unknown 140 45 Out Unifilter Top removed and opened up.
None jhanlon188's setup

Bub Dresser Dogs Pipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
500-1000 ft. 122 45 Out Stock, Paper Stock
3
None just4fun's setup
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Raask Dragpipes

Elevation Main Jets Pilot Jets AI Air Filter Snorkles Air Screw Turns Shims Notes
Unknown 145 42 Out Unifilter Top Removed
3¾ (Still fiddling)
1 (0.05mm) piper's setup
Pipes are open and LOUD!
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