Keihin Carb

[Harry]

Gent's why is the Keihin carb so problematic on the GasGas but seems to work fine on many other brands without having to use aftermarket jetting?

 

[wise old man]

I don't really think it is a GasGas thing I remember Suzuki RMX was a bit of a pain to jet correctly. From memory the carb has some issue with choke circuit and airscrew you have to be careful not to overtighten air screw or you can have bleedover problems. From what I have seen most GasGas bike come from the factory very rich and can be fixed quickly with a couple of standard Keihin jets. Jetting is a very personal setup thing and everyone has their own recipe but thats not to say the carby won't work perfectly well with minor jetting changes as any new bike requires. just my thoughts. Andrew.

 

[Cruiser]

You ever try to get the jetting right on a 98 KTM 300exc??
Its all carbs, like the man said, jetting is a personal thing,, Mine is real close first try..
Steve

 

[GMP]

Its no big problem, you just have to know what you want and how to acheive it. There are no perfect setups for everyone. The two things I think make a bike hard or easy to jet, assuming the carb is sized right and motor is in good shape, is the slide # and the head (squish). If the slide is wrong you will go nuts trying to correct it with needles. Having the head modified will improve effeciency and jetting consistancy.

 

[eff]

My CR250 had the same carb and I never had it running properly. I've learned a lot since then, and had my '04 DE250 running reasonably well with std keihin jets/needle.

This year I put in the LTR kit and I am very impressed with the change. The power delivery is wonderful, it runs cleaner and stalls less in the tight stuff. I think that needle is well worth the modest investment.