Early 90's RM Powervalve question.

[Hucker]

Hey, just took the powervalve cover off my RM (complete rebuild, decided to play with the engine today :) ) I actuated the powervalve and to my surprise they are shiney clean. I guess that Silkolene Pro 2 does its job. Ok now for my question there is a knob on the left side of the engine case, right besides the powervalve. I've never adjusted this at all, just look like a dial for a better word. I'm guessing this has something to do with how far the powervalves open up. Can anyone clarify this for me? And maybe a setting even? I'm just wondering if this little dial might help open up the bottom end a bit...

 

[RM_guy]

I think the PV on the ’91 is the same as on my old ’92 RM. If I remember the tension is suppose to be set at one turn (clockwise). You’re right, the spring pre-loads the PVs and determines when they open. More tension and they open at a high RPM. The PV is used to allow an engine to have top and bottom end power. Depending on how you set the tension will affect the power delivery characteristics.

After you set it take it for a ride and see if the power is right for you. Don’t be afraid to play with the pre-load setting. Keep in mind that if you goo too loose on the pre-load the PVs will bounce on hard landings and rough terrain.

Good luck

 

[Hucker]

Hey thanks for the reply, atleast now I can fool around with them and see if I can get some more bottom end out of this thing :)

 

[kimoaj]

Hey

Hey man !

you`d might like to check out this web page, contains alot of info on power valves , and top end rebuilding.Click here man


Cya.

Joakim