Probably need a valve job/shim kit. Timing issue? Timing maybe off. Valve work is probably one of the hardest jobs to tackle. Lots of good help on here to DIY. Shops charge about 400 to 500 dollars. Remember to start simple. Check spark plug/s, gap, sensors etc.
Alright i have do some test .... Every speed do this problem WHEN i turn the gaz in maximum but faster ......when i turn the gaz normaly its ok ......but when im in neutral position i can turn it fast and every thing is ok
I go see my spark soon but what is the best for my bike and whats the best gap i need ???