Bike ran great, then began to miss. I replaced coils and plugs and plug wires and now have bright spark. Issue is that I moved the timing plate while replacing the points and now it won't start. I can't get it to spark a plug while turning the engine over with allen wrench when the timing mark on the flywheel is opposite the mark on the housing. It always seems to spark before the mark gets to the housing mark. There's no more adjustment for the points plate to move. I have to be doing something wrong, but can't seem to figure it out! Any input would be greatly appreciated!
Thanks, Steve
Your timing is set by 2 things: plate position and "points gap".
1) Set the correct points gap only at the highest part of the ignition cam. You'll need to rotate the engine to achieve this precise crankshaft position.
2) Once the gap is correctly set, then the points should open right when the Slow mark appears in the timing window. This is achieved by loosening the points plate and changing its angular position. A 12V mini-lamp connected between the engine case and the flat spring of the points is the best way to see this event. Ignition key must be in the ON position, of course.
3) To finish the job, we highly suggest you use an ignition strobe lamp to time the ignition at high RPM using the Fast mark. Again you'll be rotating the points plate. Only after this last step should carb adjustments be attempted.
NOTE: Any time the ignition is ON, the spark plugs should be allowed to "fire" by having plugs in BOTH caps. Plugs can either be installed or laying on the cyl head, but they must be allowed to fire.
Hope this helps.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Richard, thanks for the advice. Your explanation was much clearer than the manual I was using. After trimming and bending, my .015 gauge worked like a charm to get those pesky points set correctly! Also, using a light to determine when the points opened seemed to be a better method than the buzzer I had been trying. As soon as I touched the starter button I was back in business!
Thanks again, Steve
I am so glad that worked out for you !! The whole time I was writing it, I kept thinking 'this guy is way beyond all this and thinks I'm an idiot', but I simply couldn't see any other path to your trouble. So I crossed all my fingers and submitted it.
> Now that you have it, you can use a Sharpie marker to place a line across the points plate and engine case. If you need to mess with the points out during a ride, you'll be able to gap them without feeler gauges simply by making them break right where the plate is set.
> Usually the auto-advance (AA) springs need replacing every 10 years or so. If you have not done so, you can order new springs for the next time you go under the front engine cover.
> For best idle and most power the AA also needs good lubrication to perform its best.
> Due to mechanical wear of the AA itself, it is always best to strobe time the engine at high RPM to the F mark as the final step in setting the ignition timing.
Hope this helps.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Thanks again, I've ordered the A/A springs, since mine are 50 years old. I'll put them in place before I close up that front cover.
Steve
And don't forget a tiny dab of high temp grease on on the moving/sliding parts of the auto advance unit.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
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