i have a 300ex with a 120 main jet right now, and i was wondering how many i should go up, I have a white bros. pipe and a UNI air filter with no air box lid on. Thanks Dan

 

I was looking on white bros site and under tech help they have the manual for the e-series on a 300ex. in it they say you should go up one to two sizes on the main jet when using a aftermarket filter and no air box lid.

you should download and print up the manual it has tons of tuning tips. http://www.whitebros.com/tech2.html