87 250R carb?

[josephnone]

hello all. I have an '87 250r that has the JP head bored out to a 280. It seems like I'm not getting it to rev. high enough on the top end. I have a bills pipe and the keihn 39mm carb in it. I believe it has the stock rev. limiter on it. I'm not sure if the carb isn't big enough to give it enough fuel on the top end, or it's the rev. limiter. any help?

[2004exrider]

main jet may be a little lean?

Jimmy

[wilkin250r]

Originally posted by 2004exrider
main jet may be a little lean?


I doubt it's lean. These 2-strokes get richer on the top end, which is why the dirtbikes have powerjets. If anything, it's rich.

Not only that, but a 39mm carb should be plenty big enough for 280cc.