[FCR 41] Hesitation on deceleration

Hi to all.

Like my friend atreiu, I have a '91 XR 600r with 644cc, worked head, hotcams and open exhaust. The pumper is a 41mm FCR, the jetting is the same suggested in the thread, except the main jet (#185).

I have the following issue: on acceleration and at full throttle all works perfectly, but when i decelerate (also slightly), the engine becomes very irregular, and it pops. Then I have to close and reopen throttle completely, if I want that the problem ends. What happens?

my fcr came very lean. I put in a larger idle jet, I think if I remember I started with a 48 and ended up with a 60 or 62 I can't remember for sure.

If you go to sudco.com they should be able to help you.

Good Luck


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