Ok I just installed a 400ex carb with a stage 2 jetting on my 250x. It has a RCM exaustand smaller front and rear sprockets. Ok it runnes great at idle and when you just cruise at low throttle but when you get on the gas it really starts to bog down. I am thinking that since the carb is probably set up for a 400 then I am probably running rich. (Am I right?) Well if so I was told I could adjust the needle in the carb to lean it out if true how much should I move the needle. Or if there is something else I am over looking please help.

 

check what the jet sizes on it are, and the needle clips. i would go down a clip at a time untill the midrange is good, but get the main jet dialed in right 1st, then go to needle.

 

How do I go about doing that? And what jet do I adjust?

 

Anyone?

 

I recommend buying a manual. It will be the best investment you can make if you work on quads yourself.

 

Almost forgot, put in a new plug, run the bike at wide open throttle and kill it(at WOT) then pull th eplug, it's supposed to be a light tan, brownish color. If it's black, youre rich. If it's white, you're lean. For the main, you can't just adjust, you need to actually buy the jets. I would buy a DynoJet Kit Good luck.