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Discussion Starter #1
I adjusted the valves on my 660 now it wont stay running and its very hard starting im assuming the intake valves are too tight? But i dont see how i used a feeler guage and everything i dont understand it seems like the feeler gauge doesnt fit in there all the way no matter what like the exhaust valves. So do i just need to back off my intake valves? And do the intake valves not let the feeler gauge in all the way?
 

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Did you have the engine in the right position? I think you should have it a top dead center but you might want to check.
 

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Discussion Starter #6
I had the valves way to tight because when i went to adjust them originally they were wore pretty tight. It runs like a top now.
 

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Master of the Electron
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What I don't see mentioned here is the need to adjust NOT just at TDC, but at TDC on the compression stroke. If you don't verify that you are on TDC compression stroke you have a 50/50 chance of adjusting incorrectly.
 

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Quadmaniac- what do you mean "TDC on the compression stroke?" Does that mean when the piston is at the very top?
 

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Master of the Electron
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IN a four stroke engine, the crankshaft turns twice as fast as the cam. The piston makes two up (Compression and Exhaust) and two down (Intake and Combustion) strokes for each power cycle.

If you just watch for TDC on the flywheel, you do not know whether you are at TDC on exhaust or TDC compression... you MUST be on TDC compression in order to set the valve adjustment.

To determine, I watch the intake valves. Turning the engine counter-clockwise using the crankshaft nut, when the intake valves just begin to open, you should have just seen the TDC mark on the flywheel. Turn almost one full turn more until you see the TDC mark again. This should be at TDC on the compression stroke.

To verify, rock the crank back and forth about 1/8 turn each way, and the valves should not move at all - you're there.
 

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Good info!!! Thanks, checking mine soon!
 
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