I've seen 5, 10 and 12 degree AAU's and there could be more. As to which bike used which, you'd have to research. The vast majority of twins used 12 degree advance and the ET ignition bikes used 5 I think. The AAU's are clearly stamped as to how much advance they supply. Cheers, Bill
Bikes 1974 Commando 1985 Honda Nighthawk 650 1957 Thunderbird/T110 "Black Tiger" Antique Fans: Loads of Emersons (Two six wingers) plus gyros and orbiters.
Thanks for the answers. Mine is 12 degrees. Thinking about it there can't be any difference between them as long as they advance clockwise. When I have been looking I have avoided ones that had been fitted to a Trident or single and probably missed some good ones.