ES2 mag pinion

Previously wrote:

Needing a magneto pinion for my 1950 ES2 restoration, I ordered a pattern part through an ebay seller. When trying to fit it I found the taper was too big for the magneto shaft taper, i.e. it would never tighten properly onto the shaft, the end of the shaft taper showed through the hole in the pinion. Useless. Put it down to experience and ordered one from a respected supplier of pattern Norton parts. Same problem, in fact the two sprockets look identical so I assume they have the same provenance. Lucky I didn't get shirty with the ebay seller. On talking to a magneto specialist, he said pattern mag pinions often have too large a taper. I am now hoping that the second hand genuine pinion which I've ordered -from Germany- will fit.

So, my question.

Has anyone else had experience like mine, how did you resolve it and why is someone making mag sprockets whichwill'often' never work?

Incidentally, if the sprocket goes too far onto the taper not only will it not tighten, it also runs hopelessly out of line with the crank pinion!

..and this is the SHORT version of this story...

Any help?

Adam

Hello Adam,

Have you compared the magneto sprockets as fitted to the AMC singles? I may be way off base here but since both types of engines used a chain drive for the magneto, there may be enough similarities to allow the mingling of parts, I have no way of comparing the two myself since I sold off all my Matchless bikes and stuff, it may be worth a try, if the number of sprocket teeth match why not? The tapers on the magneto shaft and the inlet cam shaft should be identical on both AMC and Norton singles. Check it out.

Albert