Cam Sprocket / Points Alignment?

[Bob Dale]

How critical is it that the mark on the end of the cam at the points be "perfectly" vertical when the cam sprocket is at top dead center? As you can see by the 2 photos below, mine is slightly off (at both positions, mark down or mark up). I thought that maybe it was a tooth off inside the cam but there only seems to be 2 positions to choose when assembling the cam...up or down, with no adjustment available. This problem seems to be indicative of my symptoms which include spark plug fouling and timing that is far too advanced with no way of adjusting it back but how can it be corrected?

[Bob Dale]

Here's another picture that may show a little clearer how the line is a few degrees off. The cam sprocket was perfectly level when this was taken, suggesting that the timing of the points is slightly out of phase with the valves?

[fastjoe]

Trivial
If you look at it you will notice that if it were lined up better the ignition timing would be more advanced then it is. Just make the point gap a little smaller.
Joe

[Bob Dale]

And if the point gap is set as narrow as it can be and the timing is still too advanced can the points plate be modified to rotate a little further? I would prefer to exhaust all possible reasons why this might be necessary but I am running out of options. It has been suggested in the past that my cam chain is off a tooth based on the photo of my "not perfectly vertical" line. This is what prompted me to pull the engine and dissassemble it again. That proved to be incorrect. Given that the cam/valve timing is set correctly, would there be any negative side effects from making this modification to the points plate? Or other alternatives?

[fastjoe]

Go ahead and file the slots , what ever it takes. maybe the plate was off of another model. I don't see any reason that it can't be made to work.
Joe

[bigscooter]

wow! i was going to post the same question. the CA77 i just got has the same problem. i thought the previous owner had it one tooth off. i ground some material off of the follower on the points, and was able to time it.
the other day i put a top end on my friends CA77. like you, i checked it several times, put it together, and it was the same deal. it was to far off to make up for it by changing the point gap. i ground down the points follower a little, and it timed just fine. both bikes seem to run great. i thought modifying the points was a less invasive temporary fix than cutting up the plate.
what gives? are all three bikes one tooth off the same direction?

[Bob Dale]

bigscooter...without reposting everything here, I would refer you to the Restoration Logs section where I am still dealing with this problem at the end of the 5th page on my "Houston 66 Dream" log. I thought it was working but its getting complicated again! I'm glad that yours has worked out for you.