I could be wrong, but I was told by an expert that the eccentric peg was used to locate the cam at maximum magnetic flux and should not be mucked abart wiv. Perhaps this is why PEI does not mention it.
Adjusting magneto
- Thread starter Bracker1
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Yeah, that's what I told them too........ then they went ahead and did it anyway and went faster.
Cheers, John
I forgot to add, they also laughed at me and said something like "silly boy"
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Quite right. Altering contact breaker gap will affect the quality of the spark but here we are talking about thous and if the ignition system is so near its limit that changing the dwell angle will seriously weaken the spark then it is time for a sort out. Consider that we have two, or perhaps one, cylinders. Coil ignition systems were used on Rover V 8 engines with a single coil and set of points. If they can do that then we do not even challenge them.
Problem is that the unequal firing angle on the Vincent vee twin does not give the same reading as on some other bikes. Comments please from those who know better.
Norman,
That's exactly my point. Vincents use a 180 deg magneto that has a modified slip ring and points cam to run on a 50deg. vee twin. If those flux lines are so critical, how does that second cylinder ever manage to fire? The same out of phasing happens each time the spark advances and retards too. If for some reason you can't seem to dial your spark in exactly where you want it, fine tune it with the eccentric screw.
Cheers, John
I think that we are dicussing two different things here John. One is magnetos and the other coil ignition systems. The only dwell meter I have ever used was for coil systems and I can't imagine that it could be used on a magneto. Your points about magnetos and their foibles are well made and one of the reasons that I gave up on them years ago; and yes gents, I do know that there are people out there who have used magnetos for decades and are perfectly happy with them.
Mine's a D so has coil ignition. On the Corvette it's used to set the points gap or it was until I got an electronic device which replaces the points and leaves the car looking standard. It's a hall effects sensor and was quite cheap, pity someone doesn't make them for vincents. If it were to fail you simply replace it with a set of points.
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