the old stock british motorcycles had variable advances on their magnetos, hooked to the lever on the bars like the indians and all those interesting old heaps.
what i have is an ARD, which is an aftermarket magneto from the 1960s that was marketed after the british went to coil/points in 1963, and the old farts wouldnt have it. it uses a fairbanks-morse magneto hooked to a rubber belt drive driven off the exhaust camshaft.
the belt is under the oval cover. these things were mostly for racers and chopper people, but can be retro-fitted with a rudimentary retard for starting.
this kit replaces the magneto cover with one that has a lever that can retard the points plate 10 degrees for starting.
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as is, its designed as an on/off to prevent the thing from kicking back, but as its cable operated it could probably be fudged to work at intermediate settings. but just the kit to do it costs more than a state-of-the-art electronic ignition with an automatic variable advance and no points or condensors.
i like the ARDs very much for racing, as the entire wiring harness consists of one 18-inch wire from the magneto to the kill switch, but for a practical machine for transportation, electronic ignition is hard to beat. and im interested in getting this motorcycle out of the way soon, so i can put the sidecar on it and go out on the road. so it will more than likely be the EI.
