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2007 Sticking decompressor problem

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At the end of the day a couple weeks ago, my trusty rocket got REALLY hard to kick over. No major problems, the motor was obviously not seized. I could get it bump started with a big hill, and still had great power. I could stand my 215lb self on the kicker and not budge it. If you left a foot on with minimal pressure, it would eventually push past the compression and turn over. I did not try real hard, it was going to break something if I kept trying.

Thankfully got it back to the truck with no problems. Tore it down the next day. Valves were exactly in spec, where I had adjusted them to previously.

The decompressor mechanism was binding. I took the cam holder out, cam out of the cam holder assembly. On the decompressor shaft, the part that actually pushes the decompressor plunger, the little pin that moves the plunger was bent just a tad, and the plunger was binding where it moves through the camshaft.

got around 130 hours on the bike. 102 on the meter, and I put the hour meter on somewhere around 30 hours. Been a pretty solid bike otherwise. I sure ride it like I stole it.

I will have pictures posted later this week. Wanted to add to the diagnostic information vault that we all use here.

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Have you ever had a problem like this before or out of the blue?

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http://www.thumpertalk.com/forum/showthread.php?t=877910

look at the 3rd picture there. The arrow pointing down points to a bushing in the end of the cam. When that moves out slightly it will bind the decomp mechanism. Take out the cam, and just put it in a press. the bushing will press in every easily flat with the end of the cam again

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http://www.thumpertalk.com/forum/showthread.php?t=877910

look at the 3rd picture there. The arrow pointing down points to a bushing in the end of the cam. When that moves out slightly it will bind the decomp mechanism. Take out the cam, and just put it in a press. the bushing will press in every easily flat with the end of the cam again

Thanks for the advice! I will have to check for that. From what I saw the binding was a result of the plunger sticking in the camshaft. Everything seemed to be moving just fine on the cam gear end of the decomp shaft. I can see the booger where the plunger binds going through the camshaft. As a result of this, the pin on the end of the decomp shaft was bent, almost broke off.

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