01 RM 250 power valve help PLEASE!

I am still having problems with my power valve. I removed the cylinder

and installed a new piston while I was in there. Everything is perfectly

clean and seems to operate smoothly by hand but the power valve

won't open. I've had this bike for 3 or 4 seasons now and it has NEVER

worked properly! It seems like the actuator isn't pushing up hard enough

to overcome the spring tension. I have the spring tension set to 90 degrees.

If I disconnect the rod and rev the engine I can feel it pushing up but it

won't open the valve when connected. If I back the spring tension off to the

point that the valve won't even close all the way it will work but opens way

too soon. There is a solenoid mounted to the frame that has something to do

with the power valve that was all rusted up and not working so I replaced it

but that was last year and it didn't make any difference and it cost $100!

Please help! I'm ready to just sell it and buy a KTM......... :smirk:

sounds like the governor mechanism in the bottom end is probably gummed up

also did you check and make sure the rod linkage did not pop out of the actuator arm down inside the motor?

You need to make sure the power valve operates and is totally clean. Dont ever do a topend with dissambling the powervalve to inspect and clean it. That would be like eating your morning cereal without the milk. Remove the tensioner spring and make sure you can move the valves freely, there will be a small amount of tension from the other springs. Does it fully open and close? Check the valve timing too to make sure the side valves open when they should. I am not sure if you can screw up the timing on an RM, but I got careless on one of my KTM's years back and didnt doublecheck resulting in them closing with RPM.OOOPS! Then clean and inspect your governor. Inspect that the rod goes through the case to cylinder without rubbing on anything too. The rods can get bent while installing the cylinder if your not careful.

Thanks for the replies guys!

I took it apart today and the governor ( number 19 in this link ) http://shop.thumpertalk.com/oem.asp?partcategory=88211&manufacturer=5&category=3&year=2001&model=2002

is clean. I disassembled it and found 6 ball bearings inside. All clean and no

wear evident. It seems at a certain rpm these balls will move outward and

cause the governor to expand pushing directly on the actuator ( number 21

in the same diagram ). This causes the 3 balls to be forced up the ramp of

number 23 and a rotational motion pushes upward on the rod.

I took everything apart and can only see some shiny spots on the ramps

that the balls ride on. everything else looks fine.

Does anyone know of a test procedure for this assembly?

Thanks in advance!

Hey Shovelit, did you ever get your bike figured out? I am experiencing the exact same thing with my 01 RM 250. Here is my link: http://www.thumpertalk.com/topic/985230-2001-rm250-lower-end-power-valve-problem-no-power/ . I was thinking of replacing the actuator which has the 3 balls, in an attempt to resolve the issue. However, you said that you were able to disassemble the Governor, how did you take the Governor apart?

Power valve

Hey sorry to take over the thread kind of but i need help with my power valve. Just got a 93 rm125 and got the motor rebuilt and trying to work out all the kinks. Qhen idleing should the power valve actuator arm be bouncing around or should it be in one spot? Also it doesnt seam like ut wants to open but feels fine if i move with my hand. I have a video of it but dont know how to put it up. Any help or comments in general will help. Being wrenching for years but first time messing with this valve.


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