Author Topic: magneto connections  (Read 490 times)

Offline delboy

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magneto connections
« on: 21.03. 2021 21:17 »
can somebody please tell me if the ht leads on my a7 ss magneto have to go to a  specific side of the engine , or can they just be connected anyway round , at the moment the upper ht lead is connected to the off side cylinder ....thanks

Offline Minto

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Re: magneto connections
« Reply #1 on: 21.03. 2021 21:21 »
I believe that the system is a wasted spark one so each plug fires on both the ignition stroke and at the end of the exhaust stroke, so should work either way, but don't take that as gospel or words of wisdom of any sort. I'm probably wrong, my wife tells me I usually am.
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Offline delboy

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Re: magneto connections
« Reply #2 on: 21.03. 2021 21:26 »
thanks Minto i will wait for some more replies

Offline Bsareg

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Re: magneto connections
« Reply #3 on: 21.03. 2021 21:37 »
Your wife is correct, you are wrong again.😁 Remove a pick up lead from mag and rotate engine until brass appears, that lead fires whichever cylinder is on compression stroke.
Helston, Cornwall C11,B40,B44 Victor,A10,RGS,M21,Rocket3,REBSA

Offline Minto

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Re: magneto connections
« Reply #4 on: 21.03. 2021 21:38 »
God, I hate it when she's right. Lol.
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Online groily

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Re: magneto connections
« Reply #5 on: 22.03. 2021 07:45 »
Yup, you need to set things up correctly - there is no wasted spark, they're alternate sparks one at a time. So the mag has to be set to fire the piston that's on compression. Some people prefer front pick-up to the left, others to the right. I set my bikes 'rear to the right' every time so I don't have to think about what's what on any particular machine.

To save having to peer into the gloom looking for the brass bit through a pick-up hole, the rear (gearbox side) pick-up on the mag is fired by the lower lobe on the camring, the engine side one by the upper lobe.

But even if you muddle up the pistons, swapping the plug leads when it won't start should solve things.

Bill