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CB500 Timing marks - what's what?

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StPeter:
This may seem a dumb question but I've always believed that you can open your mouth and appear dumb or keep it shut and stay dumb . . .

I've been working my way through a basic service and have come to the timing. The consensus seems to be that static timing is the way to go and a strobe just gives you the reassurance that your advance is working. I've set the points but when I come to the static timing I'm not sure of which of the marks I should be using. Correct me if I'm wrong . . .
In the first pic, The "T" mark is the one on the left and is TDC for No 1 on compression stroke.
The "F" mark is the one on the right.

Why I'm confused is that the guide here http://www.sohc4.net/index.php/troubleshootingignitions-gettingtothepointsontime/ shows the other set of marks lined up (see the second pic).

Please can someone explain which mark is which and what the others are?

StPeter:
Thanks for the confirmation, OJ. I feel marginally less dumb today!

StPeter:
Spoke too soon, I think.
I've timed up 1 & 4 - it was too advanced (halfway to the max auto advance lines). When I try to time up 2 & 3, I have swung the points fully clockwise on the back plate but the points are still opening too early. Surely something wrong.

Any contributions from you advanced guys to help me feel less retarded would be much appreciated!

StPeter:
I've no idea - they came with the bike! Good point (no pun intended) I'll pull them off and have a look. Probably best to replace them anyway.

The odd thing is that the bike was running - albeit a bit rough. No 4 pipe wasn't getting as hot as the others and a service was well overdue. I was going to check the electrics before I ripped the carbs apart. I thought I'd found the problem when I found No 1/4 static timing was about 15deg btdc. The best I can get is No 2/3 to about 10deg btdc. Obviously it doesn't like this 'cos it won't start at all now. Boogger!

Bitsa (Ralph Wright - RIP):
Hi,
Only my opinion but if you do change the points get the real ones pattern just ain't worth the bother.You might also want to check the base plate some pattern ones float about a bit and naffs up the point gaps.There is a thread on the 750 board with the same problems you are having.
All the best
Bitsa

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