Hello everyone. Just discovered this forum while doing some research on a chronometric tach for a 1957 A10 rat project I'm building out of an old chopper. It's posted on the Britbike.com forum if you want to see it. Anyway, it's up and running, and if it would stop raining and snowing here it's ready for the road, except for the instruments. So here's the story:
It appears that A10 tach cables are clockwise rotation, driven off the mag gear. All four of the spare chrono tachs I have are clockwise needle rotation, but it takes counter-clockwise cable rotation to make them work.
I know that you could order chronos in any configuration you wanted, but this seems strange. One of my spares is mounted on what I thought was an A10 mount, which fit on the rat A10, but the tach is the wrong rotation. Does anyone know if the later A10's with the tach drive off the oil pump were opposite (CCW) cable rotation? That would explain why the BSA setup is wrong for the '57 I'm building.
Any help would be appreciated!