2002 KX 125 High Rev Problem

[jminn]

This problem started recently when bike is opened up it starts acting like it is over-reving. Not sure on the terminoligy but it wont maintain a consistent rpm in the high range. The bike does it in neutral and in gear. It also seems like the power falls off like an early over-rev problem. I recently replaced the ring, but it didn't start doing this until I had about 2hrs on the new ring. Is this an electrical problem, or maybe something to do with the powervalve. Any help would be greatly appreciated as I don't have a clue as to where to start looking.

Thanks,
Jeff M.

 

[Bizerk]

Could be running too lean. Start by looking at your spark plug. Should be light brown in color not white. There are many threads here about carb tuning and how to check to see if you're running rich or lean. I know from experience that if the pilot jet is too lean, the bike will rev to the moon! Could be lean all over but start by taking a look at some of the threads here on carb tunning. Also visit Eric Gorr's website on carb tunning. Great stuff there.
http://ericgorr.com/techarticles/carbtuning.html

While the bike is idling you can slowly pull the choke lever and see if it gets better. Does the bike bog at all? A lean bog boooaahhh...when you try to accelerate can be a sign of running too lean as well.

Unfortunately there are several things that could cuase your problems. Yes electrical-timing can cause this too.