power valve

I would say fix your power valve. It's not that hard. I just bought a 2002 RM 125. The power valve rod wouldn't move on the one I bought. When you take the clutch cover and right side main cover off you will see the power valve linkage. In my case it was stuck. There are 3 little BB looking parts that act as bearings. There are 3 cut out grooves in the linkage and one BB goes in each cut out hole. Mine had 2 BB's in one hole and it was restricting the movement. That rod should just move easily up and down with no restriction. The power valve is opened my centrifical force. It should be an easy fix, but it is a little time consuming. I wonder if power valve issues are a common problem on these RM 125's. Good Luck!