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Sensei
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The equation is simple....82 divided by 15.....equals 5.466666666666 (ad infinitum) crank rotations between repeating positioning of any one link.....
so during one minute at idle (1200 RPM), every link in the chain has been in that particular position about 220 times ...and been oiled about 220 times.....
 

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Maths is not my strong point.

As a sort of thought experiment, I envisaged taking the top cover off a 175 engine and painting the uppermost cam chain link white, along with the matching teeth on the cam sprocket, then rotating the engine via the rotor bolt, then counting how many rotations of the crank took place before the mark on the chain aligned with the mark on the sprocket.

Intuitively, I would have guessed at a lot more than 5.46rec crank rotations. Next time I have a motor on the bench I'll satisfy my curiosity.
 
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Sensei
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To rematch BOTH top marks will take twice as many rotations.... The chain link will "top" once at the 5.466666666666 rotations, but the 30 tooth cam sprocket will only have turned 2.5733333333 turns.....
First "double" alignment will be at ~10.93222222222 crank rotations......
 

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I'm the same, Charlies on one machine and Points on the other. I have to "average" out two readings. Indulge me here, I might be mechanically incorrect so please put me right if I'm wrong. By averaging out the two readings, I'm assuming that the spark will fire slightly later than it should on one cylinder and slightly early on the other. Does this mean the early one is getting ignited while the piston is still rising? If it is, I've wondered if it would be best to have one cylinder bang on and the other late, igniting it on it's downward stroke and pushing it along in the direction it's already going. I'm guessing 'F' is designed to be slightly later than TDC but what if averaging puts F too close to TDC? Perhaps the difference between the two is much more than any "averaging" could possibly influence, I don't know.

EDIT : I'm wrong here. Reading up on it, optimum spark happens before TDC, the above video should have told me that. ;) So averaging will still have one cylinder firing a little earlier than it should, but still before TDC.
 

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I have a charlies p ignition. Turning the engine counter clockwise should my timing be slighty before the F and T mark because it states that i need to average out the timing. Is there a video on this specificly for the175 cl?
 

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Put a strobe light on it and run it, any variation between the cylinders will show up as a double set of marks showing when the light flashes.
 
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