1962 A10 Flash, Starts, but won't Pickup

[jhg1958]

Many years ago when I was a young man. I bought an old A10. It did not have a spark so was told that damp in the mag causing problems.  I was told that The cure was to bake the mag in the oven. I did this and hey presto it worked.

Not sure if this is your problem or the cure but it may be worth thinking about.

John

[Adler]

Hello TerryB,
I am a newbie in BSA A10s, but I actually had the same problem on my Zündapp K500 (a boxer twin). In the beginning I sorted out the carb problems (main jet, needle height, petrol height controlled by the float needle, etc.), next was the manual (battery) ignition timing. I found, my Zündapp being veeeery sensitive for a "wrong" position of the ignition lever at the handlebar - do not laugh, but this in the end was solving the problem. The machine runs perfectly since then.
With my A10 I had a similar problem. Starting OK, idling as well, revving not so well ... same procedure, carb check, some adjustments in the beginning right according to haynes manual and other sources. Then the magneto ... I admit obviously being not sensitive enough to achieve the right spot on timing for somehow 34 degrees BTDC, so I eventually found the very good solution being presented by Mr. Orabanda here:
https://www.a7a10.net/forum/index.php?topic=947.msg6520#msg6520
I do not have a milling machine but elongated the three holes to slots by manual filing and was very satisfied with the result. Having the magneto somehow timed as good as possible at first place, I started the machine and tried to fine adjust the timing by rotating the magneto and it works fine for me since then (thanks to Orabanda (Richard)).
Maybe, TerryB, you can try this for yourself. If a machine was running once, why should it not run again. Good luck.
Best regards, Manfred

[CheeserBeezer]

I really don't think it's a timing issue, more likely a fundamental or simple issue with the mag itself.

[BagONails]

Me too. Assuming you know valve timing is correct, compression is OK and you've done a proper leak down check?

Its starting to sound like weak spark breaking down under compression and/or ignition timing 'scatter' which all points to magneto.

Have you been able to run it well enough to check timing with a light?