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Discussion Starter #1 (Edited)
Okay.... after several issues with my 07 thruxton carb, I’m about to have a literal breakdown.
Parts and rebuild kits seem extremely rare to find. Can anyone help?
Open to ideas from anyone who has exp converting to EFI.
Mostly just need the damn parts to rebuild it though.
 

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I own two carbed Triumph twins and cant imagine anyone wanting to convert to EFI, but that's just me. If you wan't a EFI bike it would be simpler to sell your bike and buy a EFI one. Second choice would to buy a wrecked one and use the parts to convert yours. Fuel tank, wiring harness, throttle bodies, ECM, ignition system, flywheel, sensors, etc. It's a long list of things
 

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There is really not to much to rebuild on our carbs. The needle valve needs to be replaced when the rubber tip dries out. There is not much else that goes wrong. Maybe the float bowl gasket once in a great while. The floats if you some how crack one but very rare to see that. The jets last for eternity even if they get gunked up from sitting they are easy to clean. The throttle valves need to be cleaned once in a while. All the carb parts can be purchased at any of the OEM Triumph parts houses. Bike Bandit is who I use most often.
Don't melt down. Carbs are not tough to learn and understand and actually quite simple and reliable. No electronic stuff to go wrong on you.
 

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Okay.... after several issues with my 07 thruxton carb, I’m about to have a literal breakdown.
Parts and rebuild kits seem extremely rare to find. Can anyone help?
Open to ideas from anyone who has exp converting to EFI.
Mostly just need the damn parts to rebuild it though.
What was the original reason for you wanting to rebuild your carbs?
 

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Rubber tip on the needle valve (???) What's that all about, don't have it on my carbed 790.
You certainly do. Unless your carb is from back in the 70's when it was brass to brass for the needle and seat seal.
The needle is what seals the fuel flow as the float rises. Yours has a rubber tip -
 

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Rubber tip on the needle valve (???) What's that all about, don't have it on my carbed 790.
Keihin carburettor float needles have a Viton rubber tip for proper sealing when closed.
opposite to the rubber tipped end is a spring loaded tip where the needle contacts the float tang in order to provide a smoother opening and closing of the needle valve as determined by the float. this creates a more precise flow of metered fuel into the float chamber

even the slightest amount of wear on the rubber tip does affect carb performance by allowing fuel leakage into the bowls and thus upsetting fuel height. I think the rubber also hardens with age that is detrimental to proper sealing.
I replaced the float needles a couple of years ago and it cured my erratic carb performance

even the Amal carbs had a Viton rubber tip except for a time in the '70's when they used a plastic needle that used to unseat due to engine vibration compounded with the lighter in weight plastic needles and the fact that plastic does not seal as well as rubber thus creating leakage and causing erratic idling.

to the lennon.roach.07 what carb parts do you need?
slides complete with diaphragms, float needles, main jets, pilot and idle adjust needles are all readily available and all that you should need, along with carb cleaner

google the Jenks guide for setting up carbs for further help
 

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Discussion Starter #11
Bonza,
I managed to find the pilot jet, main jet, and the idle needle complete with the black oring/washer/spring. Couldn’t find the velocity tube that the main jet screw into. Was hoping to replace the parts I was able to find in hopes for a fix.
It’s always leaked a little bit when the bike is turned off. We tried to tune it ourselves and that’s when we encountered the issues. Backed the idle needle off about 2 1/4 turn. Managed to get it to a steady idle but when we apply throttle, it bogs and then dies.
keep on mind I have k&n air filters with a D&D ex. system
 

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Bonza,
Couldn’t find the velocity tube that the main jet screw into.

It’s always leaked a little bit when the bike is turned off.
by velocity tube do you mean what is some times the holder? there's a photo of in the Jenks guide but I dont have a part number

if it leaks a bit that sounds like the float height/fuel level isn't correct

there's a wealth of info here in the carb section Great source of info - Links to maintenance, tuning, modifications and so on
 

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If it leaks a little after shut the engine off - try a close the petcock valve. If the leaking stops that tells you the needle valve is letting fuel past the seat and needs to be placed [ x2 ]. Common problem. The tips dry out.
As mentioned checking the float levels is worth a look also. Easy to do with clear tubing off the bowl drains.
As for your problem - Did you take the top diaphragms off or out? That sounds like you may have an issue there is it idles fine but dies when throttle is opened. I really doubt the main jet holder is bad - You may have removed and installed it up side down? That can give issues you are describing.
 

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I agree with @Back2-2 's two post. Usually only the rubber parts fail, float needle and bowl gasket is all I'v ever replaced. The brass parts are usually good unless someone drills, warps or cross threads something. As I used to tell people when I had my shop, carbs can usually be rebuilt unless it catches on fire and someone tries to put it out with an ax.
Did your bike ever run good? If yes what happened rite before things went bad? Did the bike sit for long periods of time? If so the green crud that grows inside a unused carb can cause the problems you describe. What jet changes were made for the intake and exhaust mods? Did the problems start after the breathing mods?
 
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