Would appreciate any ideas on what may be wrong with friends bike. He will start off and 1st and 2nd gear will be fine when he shifts into 3rd and attempts to open her up and run it through the gears it will break up and spitter and sputter. It has a new top/bottom end and to try to fix it he has replaced reeds,cleaned adjusted carb,new airfilter,cleaned adjusted ATAC valve. He is goin to replace Cdi next . When he adjusted carb he ran it through the gears on a car lift and it seemed to be alright but he rode it on the trails and it sputtered like it did before. It had this problem last year and it all of a sudden stopped sputtering and fixed its self. Any ideas would be appreciated. Thanks kevf