Does anybody know the size of the stock main jet on the klx250sf? it has the keihin cvk34mm carb. I purchased a big gun evo slip on exhaust. Wanting to avoid the 60 dollar dyno jet kit i would rather buy a main jet. Big Guns tech support suggested i go up a size or two in my main jet. But whats the stock size to base my selection off of????

 

I don't think it's a matter of just changing the main jet. I believe you may need to adjust/replace the needle and remove the plug to get to the mixture screw.

 

as per big guns tech support they recommend i go up one size in the main jet.