Removing magneto drive gear

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mjf65
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Removing magneto drive gear

Post by mjf65 »

I'm hoping someone can help? I managed to get a gear puller but I'm not happy with the threads in the gear, it's only going on one full thread before it tightens up and I don't want to damage the internal thread. However I do have a decent two legged puller which looks like that might work if I can get two lengths of threaded bar, nuts and washers and screw them into the two tapped holes in the drive gear. Has anyone tried that method? And if so what are the thread form and size?
Thanks
Mike
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Rob Harknett
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Re: Removing magneto drive gear

Post by Rob Harknett »

Can you say what year and model bike you have.
Groily
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Re: Removing magneto drive gear

Post by Groily »

If you have a gear that has been drilled and tapped, using studs or bolts and a T piece bridge with a threaded central bolt to bear on the magneto spindle -or with a fixed central projection (in which case you'd wind nuts down the studs a bit at a time each side) - it will come off easily. You'd need to try a selection of bolts to ascertain the thread probably, but it will something common for sure.
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Rosy
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Re: Removing magneto drive gear

Post by Rosy »

mjf65 wrote:I'm hoping someone can help? I managed to get a gear puller but I'm not happy with the threads in the gear, it's only going on one full thread before it tightens up and I don't want to damage the internal thread. However I do have a decent two legged puller which looks like that might work if I can get two lengths of threaded bar, nuts and washers and screw them into the two tapped holes in the drive gear. Has anyone tried that method? And if so what are the thread form and size?
Thanks
Mike
I had this same problem when I came to remove mine with a new puller, the threads in the mag wheel had a build up of crud so I just sharpened a metal scribe and cleaned around the threads. I was surprised how much build up there was in the threads, but it worked the puller screwed all the way in.
mjf65
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Re: Removing magneto drive gear

Post by mjf65 »

Rob Harknett wrote:Can you say what year and model bike you have.
1960 AJS Model 31dl
MalcW
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Re: Removing magneto drive gear

Post by MalcW »

mjf65 wrote:
Rob Harknett wrote:Can you say what year and model bike you have.
1960 AJS Model 31dl
I have the exact same model. My extractor only screwed in 2 - 3 turns, but working it to and fro got an extra turn or so. That proved more than adequate to break the gear free of the taper.

Malc
Reynard24
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Re: Removing magneto drive gear

Post by Reynard24 »

I too have had problems with the so-called extractor only just engaging in the gear-wheel internal thread - If you happen to have a Norton fork top nut available it is the same thread as the gearwheel so you just need to drill through and tap the damper rod hole for a slightly thicker bolt and you have an alternative.
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