Need help:CR125 powervalve problems

So at the beginning of the summer I bought a 2001 CR125 with a blown top end for 800 bucks. i bought the top end for it and replaced it not long after. I guess the part was faulty and it blew up again while i was breaking it in. I called the place i bought it from and they sent me a new top end kit as well as replaced the cylinder since it was shot now.


The parts were backordered so i just got it out back together yesterday and am done breaking it in but it has problems hitting the powerband. It kind of like sputters a little bit first and then goes into the powerband with no problems. From what I can tell it seems like the powervalve is not opening properly, like it is opening late. Once it is in powerband it runs fine. i should also add that it did this before it blew last time too so I dont think i messed up something switching the cylinder or anything. The powervalve is a little loose but from what I have read that shouldnt make much of a difference, but if it does how can i fix this? Also, are you supposed to be able to pull the powervalve straight out without looseing anything? It basically slides out if you pull on it and im not sure if itsupposed to do that.


I loked into it a little bit but havent really found any direct solutions. The only thing I found is that it might be the Servo Motor? does anybody thbnk that may be the problem? Any help would be greatly appreciated. Thanks in advance

cr125 anon.jpg

2001 cr125 uses a mehanical powervalve not a servo ... only the 2004 uses servo.

Based on your description of the problem it sounds like it could be your jetting. Which might also be the cause of your first piston failure.

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