Alton do an alternator for bikes like the BSA A10. It is the same size as the dynamo and an easy fit.

Only real difference is it is belt driven.

I just can't imagine where you would easily fit an alternator for something like M20s.

email (option): sacombsashtrees@hotmail.com

Thanks a lot to you all.
I'm located in Israel. These small alternators are also fitted on other engines and generators.
I will think it over again.
I intend to take the drive from the magneto.
I will post as soon as something will proceed.

Hi Patrick,

"Alton" also does an alternator for the M20
Which is a direct replacement for the "Lucas" and driven the same.

I have one of them on a WM20 ad it works great, only add some noise.

Noam.