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2007 yz 250 no power

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Bought a seized yz 250. Stripped it all down and found cracked piston skirt was cause of the seizure. Also noticed the governor bearing was completely destroyed. I rebuilt the bike with crank, bearings, piston and seals. At first I had no spark so I multi metered everything according to the manual. All checked out good so sanded down the frame where the coil bolts onto and had spark. But te bike has no power. Hardly any at all. It's hard to start as well. The reeds are ok but has one little flake that's a bit loose. I took powervalve cover off and the linkage would not move when I blip the throttle. Disassembled all again and didn't notice anything out of the ordinary other than the spring tension was a little weak but that's it. Took off case cover to inspect governor and te new bearing was wobbly and on its way out. I don't know what else to do. I want this bike to rip. I bought it to replace my 125

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Everything was installed correctly. Not my first rebuild. I put in a new plug cap. Yamaha metered the coil and said was fine. I have spark now. Issue is no power and powervalve linkage not moving. Governor bearing trashed again

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The power valve governor has 3 bearings from what I remember. One on each side and the odd needle one in the center. Which is going bad?

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The bearing that sits in the crankcase housing. Even a hairline crack in the aluminum bearing holder in the right case 

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Replace the reed petals first thing.

The bike will NEVER run right without good reeds. Even if they are warped can mess it up.

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3 hours ago, Smitov said:

Everything was installed correctly. Not my first rebuild. I put in a new plug cap. Yamaha metered the coil and said was fine. I have spark now. Issue is no power and powervalve linkage not moving. Governor bearing trashed again

It wont have any top end if the power valve isn't opening.

Also, double check your ignition timing. 

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Pull the gov all the way down to the rod only. It sounds like it's bent and destroying itself. Also, repack the silencer if you have not. But the PV not moving, and the Gov eating the bearing, sounds like a bent shaft. 

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I'm thinking that now too. I'm gonna chuck it in a lathe and check for trueness with dial indicator 

Tht was the best advice I'd received yet. Thanks!

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