02 Honda CR-125R no low end power HELP !!!!

[reeltime123]

I need some serious help here,My CR-125 has no low end power at all. I recently bought a 02 CR-125 , it needed a top end kit so I Installed a new vertex piston, rings,wrist pin while I was in the motor I changed the clutch. After assembly It has lots more compression and more power but still no BRRAAAAAPPP!!!. So I brought it to the track, After riding another 02 I know I have a problem , Is there a chance that my power valve is not working or incorectly adjusted? If so what is the correct procedure to check it out and set it.? Any help wold be a god send thanks!!!!! :bang:

 

[Uchytil]

The other CR may have mods (check with the owner). The 02 motor is bad on the bottom. When you did the top end you should have pulled the pv, it's easy and they do get carboned up. You can check it easy enough by removing the pv cover and pipe/ex man. Then disconnect the clip and spacer from the pv and rotate by hand while observing the pv move through the exhaust port. One easy trick for that motor is replacing the stock carbon fiber reeds with boyseen power reeds which are dual stage fiberglass. They seem to help down low. Also one tooth on the rear specket from stock will liven it up. Or send the motor out for a porting.

 

[viking20]

I guess the powervalve actuator ( that moves the arm ) could be misaligned. It needs to be set correctly when it is installed inside the big clutch/waterpump cover. Its correct that the 00-01-02-03 etc CR isnt the most powerfull bike down low , but it sounds like this is worse than other Hondas.

 

[KX04]

my friends 03 cr 125 has not much bottom end power .... but that bikes got balls up top!!!!