little problem

[nicktrx400ex]

alright i know you hear it alot but i think somthings wrong my 400ex doesnt want to wheelie nomore all it wants to do is spin and go i think my jetting may be off but not shure i have a 450r carb so someone help me out

[400eXr1d3rZ]

How much tread do you have on your tires? How much airpressure?

[nicktrx400ex]

they are not even a yr old xcrs all around with about a 1in of tread

[krt400ex]

have u done any mods just before the tires stopped grabbing anf started spinning.