Re: Boyer ignition problem

Posted by Arthur Farrow on Nov 02, 2020; 7:50pm
URL: http://silk-motorcycles.221.s1.nabble.com/Boyer-ignition-problem-tp5001882p5002063.html

So finally my son and I used a traditional strobe on it yesterday. One with fancy delay angles and shit was doing v odd things, bouncing about all over the place and the ignitions seemed to retard not advance.

We have a great video of it but its a bit BIG.

MUCH better result with a traditional strobe It's on full advance at tick over .3 inch BTDC quite reliably does not move at all when revved. Probably retards for starting then immediately advances, but you cannot see it...two stroke crank driven Boyer unit originally designed for a Norton twin driven by the camshaft therefore running twice as fast as it normally would . On the Norton it goes to full advance about 3,000 rpm so on the Silk two stroke its 1,500 rpm. 

The bike starts v well too sometimes with a small kick back. On the road it does not have a lot of low down grunt. I guess it would be nicer with a decent advance curve more suitable to the revs.

Any ideas anybody ?????????

On a couple of occasions whilst letting the revs really drop (with the throttle stop wound out) the ignition suddenly changed to firing AFTER TDC by a big margin. . This got us really puzzled until examining a video we took ..the damn thing must have hit a compression v slowly and REVERSED direction of motion!!. Sounded just fine too.