CR250 Power Valve Cables

[jrm]

On the later model CR250s (02-05), does anyone have a trick for getting the power valve cables on and off the exhaust valve when doing a top end job? I can't seem to get enough free play in the cables to get the cable ends back into the ends of the exhaust valve, especialy with the tight clearances in the housing. The manual is not very helpful on this point.

On a related note, the manual for my '05 says the cables are self-adjusting via the "spring" on the front cable and the servo motor. I have an old MXA article from '02 that says they are not self adjusting. Anyone know if the later CR250 exhaust valves are self-adjusting?

Thanks.

 

[+30]

powervlv maint

check out http://www.motocrossactionmag.com/readridingtips.asp?id=471
I still cuss often at these cables when doing a top end.
sorry dead link
1 turn actuator ccw until stops
2 push left side cable to left. if you can push it to the point where it touches the cyl its too loose.
3 10mm wrench on lock nut
4. 8mm wrench on left side cable unitl tiny bit of slack do not make it taut.
5. tighten the nut replace cover.
"the cr's power vlv servo has no way to take up slack in the cables the power vavle module pulls the same amount of cable wether the cables are properly tightened or slack...the servo moto will spend some of its precious rotation removing slack...the flapper valve will not have moved all the way up in the exhaust port."

 

[slickpuss]

I dont remember what I did exactly last top end, but I remember not taking the cables out. I remove the nut in the middle of the power valve cable guide and it separated the cable assembly separate from the power valve. That way I didnt have to monkey with the cables, they seemed like a pain to undo. And like you said the manual isnt very helpful.

 

[Wraith]

The cables should just disconnect off the servo motor once unbolted like +30 said,(well reverse of what he said since those where the instructions to tighten the cables) but your 05 might be different then my 02. I always replace the cables every topend, they should run around $20-25 for both.