Hi to all.
Being new to manual advance / retard I would like to confirm which position is full advance.
My bike is a 1934 model 9.
Looking at the points with the cover removed they rotate in a clockwise direction.
I have attached a sketch showing position A and position B for the push/pull timing clevis pin.
So would position A be full advance or position B.
Cheers
Peter
Hi Peter! When the magneto rotates, the contacts open a few degrees before TDC. In your drawing they open earlier at position B and later at position A. So B is advanced and A is retard ignition. Interestingly, at my 1937 magneto it is vice versa. The advance/redard cable is on the other side. The plasic sheet in the picture is for the ignition adjustment.
Cheers, Thomas
Hello Peter,
The contact breaker/magneto spindle should, on a Sunbeam, rotate C/W, the opposite direction to the crankshaft.
Your ignition control moves the points operating cam AC/W to advance the ignition timing so that the farthest point AC/W for your cable end fitting corresponds with full advance this being position B so at the handlebar full advance is when the cable is slack.
I hope you enjoy your Sunbeaming.
Tony
Thomas
Thanks for the info.
That's great I didn't fancy a kickback if I had it set wrong!!
Cheers
Peter
Tony
Thanks to you as well. You have confirmed what Thomas said.
When you are new to these things like I am it's great to have advice at hand.
Ta
Peter
QuoteWhen you are new to these things like I am it's great to have advice at hand.
That's what the forum is for! :)
Just a quick (and probably unnecessary) comment. Agree with the advice here but as an additional 'rule of thumb', remember that moving the ignition cam in the same direction as points rotation retards ignition, moving the cam against points rotation advances it.
Cheers R
Rick
Many thanks.
Any snippet of information comes in handy. 👍
Peter