1960 BSA M21 (AA) - {positive or negative earth?

[GLENN]

Hi! 

Can anyone advise if the 1960/1961 BSA M21 is positive or negative earth? 

Would anyone have a wiring diagram for AA M21 with Sidecar and alternator fitted to the crank drive side? 

Many Thanks,

Glenn

[neil1964]

Your bike should typically be positive earth (they were -ve earth up to early 50s, maybe 1951 - someone who knows might correct me).
There was a change back to -ve earth in the late 60s (same for cars) which is still common practice now.

Hope this diagram helps:


I would imagine an accessory loom with a pilot light/rear lamp feed and maybe brake light out to the double sided lamp that sits on top of the side car mudguard?