valve adjustment

pahako

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Omaha, NE
Is there another way to determine tdc besides lining up the mark on the rotor? The reason I ask is because the rotor on this 80 special I am working on is new and there doesn't seem to be a clear mark. I adjusted the valves using what I believed to be the mark, but it is difficult to see, and is a very small, but seems to be a clear endent on the edge of the rotor. The reason I am not completely sure about the mark is because there seems to be slightly more noise from the valves, like the gap is off, when the engine is running. Thanks
 
Common practice is to:

1 - Remove spark plug
2 - Rotate engine counter clockwise as viewed from the left side
3 - Watch for intake valve to open and close
4 - With long screwdriver in the spark plug hole feel for when the piston next reaches it's highest point
5 - Check both intake and exhaust valves, both should be loose, if not go to step 2
6 - You are now close enough to TDC on the compression stroke to allow adjustment of the valves
7 - Adjust valves
8 - Go to step 1 and repeat for right cylinder
9 - Replace plugs, start bike and adjust cam chain
10 - Your done!!!
 
Last edited:
+1, if the rocker arm is on the base circle part of the cam profile, it is close enough for valve clearance setting. Basically the valves on the other cylinder will be in the overlap/open area. The engine will tend to want to turn to and sit in the "valley" between the valve ramps on the other side that's plenty good for valve setting.
 
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