sputters at top of each gear

[joe250]

I recently added a big gun slip-on to my 250ex, along with a k&N air filter. After putting on the stuff it sputters a full throttle. I know its jetting, but too rich or lean? Also what size jets would you reccomend on my 250ex? Thanks.

Well you should be lean with adding the filter and exhaust,,,I don't know what size jets you should get but go up 2 sizes on the main to start I would think..

[barbwire44]

if it makes a blurbering sound it is rich. If it misses or pings at wot it is lean. Youre best bet is to stick a big main in and listen for the blurbering flooding sound and keep dropping the jet size until the sound goes away. Better to rich than to lean. Also to do the testing find a nice open spot with about a 10% uphill grade to it.

joe, i can set you up with a jet kit and instructions from dyno-jet really cheap. let me know if you are interested. i just got this stuff laying around in my way. its stuff left over from my 250ex kit.

[joe250]

Thanks, but i've already got a K&N jet kit, and they are the same thing as dynojet.