no topend power. help!!!!

[jasonent0613]

hello i have just put a new topend in my cr250 and it was running awsome and then i noticed the powerband was becoming ****house well not even there really, so i found on another dirtbike web site that a comon problem is the powervalve cables come loose and i tightened and then it didnt do anything.

i am sending it to my local bike shop but if u know anything that will save me from putting on the back of the truck and paying them for fixing it.

thank you in advance.. jason.

 

[mkelly04]

If I remember right the 02 cr250 has an electronically controlled rc valve (power valve) make sure the actuator motor is working and the cables are tight.

 

[Blink-182]

clean the powervalves and when was your last top end done?

 

[jasonent0613]

the topend was done last week and the power valve is clean and the actuator motor is working. the cables may be not tightened right.

 

[CarnageZ28]

Do a quick compression test. Could be possible something else was bad that tore up the last top end. And is starting on this one ...

 

[yamarider88]

I am having the same problem right now. I just did a major rebuild and put in a jd jet kit and the top end was ****! tried re-jetting several times thought that was the problem then I decided to go to the basics and check everything and turns out the cables that open it at least the right side one was hanging on by one strand and so we ordered new ones and now it is a beast. one thing you can do is rig a wire to hold the power valve open then run it down the road and see if your power comes back thats what i did to check mine. be careful the mid range hit will be pretty big and it will have no low end. also you may want to make sure your servo is working. hook up 12 volts to the black and green wires and see if she spins. the service manual tells you how to check all the resistance and stuff. also you can just open the side cover and rev it up at 3000 rpm it should start to open and be fully open at 8000 rpm. mine were kinda open not really so I had to rig it up just to see for sure. if it's just the cables it's a pretty easy fix here is how you adjust them properly. http://www.motocrossactionmag.com/m...0&tier=3&nid=F6E595A399B64522B984C9F052329215

 

[jasonent0613]

thank you