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2003 RM 125 Power Valve - On/Off or Gradual Opening? (video)

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Is the open of the power valve supposed to be an open/closed operation or should it open gradually as the rpm's increase? Here is a video of my power valve rod in action.

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That looks good to me. If you rev it slower, it opens slower. Rev it fast and it needs open to give it the power it's supposed to have.

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How much force should it take to pull up the power valve rod? If you watch this video, this guy can easily push up the rod with his thumb.

I can barely move the rod unless I grab it with a pair of pliars. If I disconnect the rod from the power valve lever, the lever moves very easily (no effort as I just took the power valves apart and cleaned it) but the rod is very hard to move. It does eventually move if I apply enough force. My bike is hesitating bad right before power band but then runs strong when in power band. I'm thinking that the power valve is not opening soon enough causing the hesitation. Then, once there is enough force to move the power valve rod, the power valve opens up and the bike runs good.

What do you guys think?

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In the second video you posted, the power valve gear was not aligned correct because the side cover was not on. Your's seems to be working fine when the bike is running. It may be a jetting issue that's causing the delay. How does the plug look?

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The plug looks brown but a little wet. I've been both ways on the jetting trying to correct this problem with no luck. What else could it be?

Edited by 2RM250s

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How do the reeds look? Not cracked or chipped and tight against the reed cage? How is compression? What jetting did you change? Read the FAQ at the top of the forum on jetting. That may help.

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