Author Topic: Magneto issues  (Read 1522 times)

Offline BSA500

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Re: Magneto issues
« Reply #15 on: 02.06. 2023 17:56 »
My mate is going to lend me his mag from his a7ss so should go quicker *smile*. Just checked the other bits and bobs and looks like a dead coil. The LT tests are fine and earths. Now I just need to find someone to fix it without having to sell my first born(she won't be happy she's 29).

1960 A7 (57 motor to SS spec)

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Re: Magneto issues
« Reply #16 on: 03.06. 2023 09:58 »
Just send it. If it's one i've done before, I'll prioritise it.

Offline BSA500

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Re: Magneto issues
« Reply #17 on: 03.06. 2023 11:30 »
Thank you Andrew that is very generous especially as I can see how busy you are.

1960 A7 (57 motor to SS spec)

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Re: Magneto issues
« Reply #18 on: 03.06. 2023 20:29 »
Not a problem. I'll turn it round in a week, at a very reasonable price.

Offline cznorbert

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Re: Magneto issues
« Reply #19 on: 05.06. 2023 07:09 »
I had similar magneto issue

luckily I saw the problem with the armature in my hand.

on one side of the coil the wire was separated from the solder, I repaired that and fixed the wire

I don't know exactly what the function of the wire is, but that was the problem, now it works.

When setting the timing, is 5/16" or up to 7.9 mm the right value, for my A7 1949 Long stroke bike?





49 LS A7

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Re: Magneto issues
« Reply #20 on: 05.06. 2023 07:35 »
That is the connection from the low tension coil to the points.

Offline Swarfcut

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Re: Magneto issues
« Reply #21 on: 05.06. 2023 08:58 »
Norbert, Service sheet 203 gives 5/16" for a standard A7, not specifying the engine type. There is a typo error on my original sheet, which shows incorrect entries for the other  A7 and A10 based Sporting Variants. Haynes says 3/8" for Star Twin and Shooting Star, again without specifying Model or Year.

 In practice because of the change in fuels over the years, simply aim for the setting that gives the best performance without pre-ignition.

   Brits call it "Pinking", while it is also known elsewhere as "Pinging"

 Swarfy.

Offline cznorbert

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Re: Magneto issues
« Reply #22 on: 05.06. 2023 10:20 »
Thanks for the info, I will work on it further based on this  *smile*
49 LS A7

Offline BSA500

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Re: Magneto issues
« Reply #23 on: 11.06. 2023 16:33 »
Update time.
 Again Andrew at Priory magnetos came up trumps. Magneto sent and repaired and back on the bike in under a week. Excellent work as usual, HT side had failed also moving contact part of the points had worn oval. Andrew put all these things right plus some smaller bits and bobs.
I am sure it would have fired first kick if of course I hadn't got the leads the wrong way round,50/50 chance 100% wrong everything  A bloody chicken would have a better success rate.
 Goes really well,still tends to spit about at the lower end but at least I know its not the mag now.
Again thanks Andrew

1960 A7 (57 motor to SS spec)