Would this carb work for a 2000 KLX300

Would this carb work for a 2000 KLX300? Its a Keihin FCR-39 with TPS, off a KTM 450exc. I was wondering if it would work, even with the TPS?

I think that a 39mm would be too much carburetion for a 300cc engine.

How would you mount it? Does it have the same dimensions as the stock carb?

What jetting would you use?

The tps is not a problem.

Ride on


I tried to mount a FCR37 on the KLX. It has the same size body as the FCR39. I was able to mount the carb to the engine and the airbox but the head pipe wouldn't fit. It would rub the carb. I had fears of boiling the fuel in the bowl.

It will fit, but it would not work very well down low and in the midrange ....

I have a 37mm FCR on my 300 and that hits more in the mid to top. It suits me as I tend to ride mine in the mid to top range. You also need to take into account that I have:

1) a 340 kit ...

2) extensive porting, polishing and valve work ...

3) reasonably aggressive camshafts ....

4) a straight through exhaust ....

a 39mm would just be too much, the klx's really dont have the rev range for a big carb .... a 35mm would be the best on a 300 ....

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