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Stumped balancing TB's
coozer - 14/2/10 at 05:42 PM

Following on from my previous post I have nearly got the thing idling nice...

TB's are off an 04 CBR100RR.

Only problem I have now is balancing the TB's, cylinder 3 is pulling 20" whereas the others pull 5". There is an adjuster screw in the middle that balances the two sides and a cold air system controlled by jets. I have tried adjusting these but to no avail, they don't have enough resolution on them like the screws on gsxr ones.

And, I just sold me set of K4 gsxr bodies....

Any ideas anyone?


big_wasa - 14/2/10 at 05:46 PM

check the shafts not bent.

Have you respaced the bods and extended the fingers ? Is one bent ?

[Edited on 14/2/10 by big_wasa]


jacko - 14/2/10 at 06:03 PM

What engine ? zetec ? if so what inlet manifold
A mate of mine had trouble balancing his TB's he had the standard 2l black top inlet manifold .
If you look at the back there is a grove between the cylinders he changed the maniford to a 170 zetec one and all was ok
Jacko


coozer - 14/2/10 at 06:21 PM

Standard TB's, no mods to them, will go straight back on the bike. Homemade inlet manifold with original ST170 injectors (ST170 engine) sitting pointing down the inlets.

All the TB's do is limit the air by the butterflys, not using the bike injectors.

I made the manifold to replicate the ST one and suit the TB's which the ST manifold didn't.

I'm thinking of some mod to the idle circuit to allow enough air for it to tickover.

This is the manifold with injector ports in original position...


And with the TB's attached...


OR, I've got two massive 55mm TB's off a TL1000 I might use.....

[Edited on 14/2/10 by coozer]


tomprescott - 14/2/10 at 06:46 PM

Have you got insulators on the injectors?
What are you running with regard to ignition/injection timing?


big_wasa - 14/2/10 at 07:15 PM

Check you havnt lost a spring out of the fingers.

The 2.0 130 ps single bod is 55mm two would be over kill


coozer - 14/2/10 at 07:47 PM

quote:
Originally posted by tomprescott
Have you got insulators on the injectors?
What are you running with regard to ignition/injection timing?


MS V3


corpi - 15/2/10 at 07:52 AM

An air leak? Pin hole leak in one of the welds? At idle a little leak can make big difference....