Question about timing on A1

Hi all, the old girl is playing up just lately, not sure if it's fuel supply or timing or shims, sometimes she doesn't seem to be running on all 6, idles good, revs good, sometimes a bit of a pop either in the exhaust or back thru carb, not sure which cylinder, getting lazy and haven't really gotten into it yet as I have another vehicle to get to work. Anyway when I was checking the timing I remembered that the backing plate is all the way to the locking screws and that is the correct spot for the firing / timing marks to line up at idle, I was wondering how the hell did that happen ??, when I did the rebuild did I just go a tooth too much somewhere ??, and should I elongate the holes so I can get a little bit more adjustment out of the timing ???, just wondering and looking for suggestions or ideas ... thanks in advance, Pete

This may help

Haggler wrote: This may help

Good point Haggler. always go back to basics ie. the service manual.
One thing the manual doesn't address is the timing advancer. If the timing advance is stuck ie. the rotor will not rotate on the shaft, you may end up setting the timing incorrectly. So the manual SHOULD also indicate a check to ensure the timing advancer is free to rotate (against spring pressure) and follow through with the installation of the pick up coil assembly. When complete and if you have a timing light, check to ensure your timing is advancing and retarding. Silly things happen sometimes like the wrong washer or machine screw being used to hold the rotor assembly on the rotor shaft and binds the mechanism so that the timing won't advance.

removed post. Changed my thought

While I had the timing light on it I did check to see if I was getting advance, and at the specified revs it was going to the full advance mark, and I also did a manual check to make sure the advancer was free and moved and did return easily, everything within specs as in the manual, I have a spare plate and pickups, might elongate the holes a bit and try it on the bike, can't hurt , as the old girl has been running good for years till now, probably be some silly little thing, cheers Pete.

Before you do that, I'd pull the assembly out of the block and index the pickup coil assembly one tooth on the drive and see if that gets you back to where you need to be. if it's too much, the only explanation could be stretch in the timing / water pump drive chain.