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Discussion Starter #1
Hey there,

I am rebuilding a 1967 Cl125a, I went to a 2 over piston bored and honed, lapped and checked the valves. I’m getting ready to reassemble the motor but want to verify the proper way to set up the camshaft. I have the clymer manual, but it doesnt help at all.

My initial thought is: set the mark on the rotor to tdc or fire, then set the cam to where the valves are all closed and bolt holes on the end are horizontal, and place the cam sprocket with the mark “O” at the top, bolt it in and adjust the valves. This is literally me guessing based on other engines i’ve rebuilt, so any input is much appreciated.
 

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You won't find a spot, at tdc, where all four valves are closed. The intake and exhaust valves on one cylinder will be closed(firing stroke)and the ones on the opposite cylinder will both be slightly open(exhaust stroke). With the crank at tdc and the sprocket mark straight up bolt the sprocket to the cam. The holes may be spaced so it only goes one way, if they are evenly spaced you can bolt on either way.
 

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Discussion Starter #4
You won't find a spot, at tdc, where all four valves are closed. The intake and exhaust valves on one cylinder will be closed(firing stroke)and the ones on the opposite cylinder will both be slightly open(exhaust stroke). With the crank at tdc and the sprocket mark straight up bolt the sprocket to the cam. The holes may be spaced so it only goes one way, if they are evenly spaced you can bolt on either way.
I was more or less on track with my assumption. Thanks for clarifying!
 
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