Actually I have a problem with flat side. On the 3/4 throtle bike is running not smooth, is going up and down on rpm. How to fix it?
Is only when i try to be stady on one throtle position, when accelerating it is not a problem.
I have 628 HRC big bore with XR only exhaus ( as far as i know is from 650 due bigger compression and bore)
may be i need rejetting ?