Ariel Owners Motorcycle Club

Hi again guys, if you read my previous blogg concerning the magneto timing having slipped then you have an idea as to what is happening with my FH engine. The advance/retard mechanism seems in good order and no teeth missing from the idler cog so ready to re-time the mag. I can get the right-hand piston to the required 11/32" BTDC. I've wedged the advance/retard in the full advance position and placed it loosely on the tapered mag shaft. The lower pick-up on the outside of the mag feeds the HT to the right-hand plug and the pick-up on the top of the mag feeds the left plug. The contacts move in a clockwise motion. Now the question: Looking at the contact breakers and the pad on the pivoting contact which moves around the cam-ring, should the pad be coming to the bottom of the cam-ring (at approx 4 o'clock) or should the pad be nearing the top of the cam-ring (approx 10 o'clock). I'm trying to find out whether its the top or the bottom of the cam-ring that fires the bottom pick-up which feeds the right hand plug
As always any advice gratefully received
Thanks guys

Hi David, the position of the points should be loosely opposite the HT pickup for the cylinder being timed - so opposite the lower pickup in your case. Check your timing carefully after tightening, as tightening the nut can move the advance/retard unit a little as it moves down onto the taper. Took me a few attempts.
Cheers

Hi Graham and thanks for the tip