Circuit breaker cam timing mark Q

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Circuit breaker cam timing mark Q


Post by doc308 » Tue Sep 29, 2009 2:05 pm

The timing mark on the cam lobe of the circuit breaker on my '48 is located to the far left of the high point of the cam ( right on the edge of the heel--not on the high point of the lobe). I've noticed that the mark in the pictures in Clymer"s and the Harley Panhead manuals show the mark to be close to the center of the high lobe. I've been trying to set my timing according to the mark on my cam and it doesn't appear right . I'm q'g whether someone made his own mark on the cam. There is no mark on the center of the lobe at all --only the one to the far left . Anyway--does the placement of this mark sound right or not? Does anyone have a picture of where the mark should be?

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Re: Circuit breaker cam timing mark Q


Post by Cotten » Tue Sep 29, 2009 2:28 pm


The mark means little more than the front cylinder side of the cam.
Its just a visual aid for installing the base, I guess.

For the ignition timing adjustment itself, the Service Manual method of using a simple bulb on leads ignores the mark.
Its all about getting the flywheel mark in the hole,
on the compression stroke,
of the front cylinder...

And then adjust the timer to where the points just break at full advance.

Gawd knows whats in the Clymer book.....


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