1964 Atlas: remove the Magneto

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Nov 10, 2012
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Hi.
I can remove the magneto because i cannot divide from the AAUU.
Please, what is the way?.
Thanks
Piero
 
The center bolt is a self extracting screw, when it works properly. Turn CCW until the AAU pops off ..... If it does not, the center bolt is stripped.

If the bolt is stripped, then loosen it about two turns, then use a small gear puller. Pull on the sprocket of the AAU, and push on the center bolt.

Slick
 
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Hi.
I can remove the magneto because i cannot divide from the AAUU.
Please, what is the way?.
Thanks
Piero
If the extractor threads on the center bolt are stripped (I suspect they all strip eventually) the bolts are available from Draganfly Motorcycles, the UK Ariel/BSA parts supplier. There are two sizes so be careful that you get the correct size.
 
If the extractor threads on the center bolt are stripped (I suspect they all strip eventually) the bolts are available from Draganfly Motorcycles, the UK Ariel/BSA parts supplier. There are two sizes so be careful that you get the correct size.

Good info, Bodger.

My bolt is stripped, but I have not devised a way to remove the bolt from the AAU so I can replace with new. I suppose the internal left hand threads are so damaged that the bolt will not come off ..... it is captive and just spins forever. Tried left hand removal as well.

Slick
 
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Good info, Bodger.

My bolt is stripped, but I have not devised a way to remove the bolt from the AAU so I can replace with new. I suppose the internal left hand threads are so damaged that the bolt will not come off ..... it is captive and just spins forever. Tried left hand removal as well.

Slick
I have had this problem often. I cant decide if it is the result of normal wear, my lack of skill or the design - there's not much meat on the extractor threads. The last time it occurred I was somehow able to "worry" the bolt off. I think I tried tightening and then rapping with a mallet.
 
If the extractor threads on the center bolt are stripped (I suspect they all strip eventually) the bolts are available from Draganfly Motorcycles, the UK Ariel/BSA parts supplier. There are two sizes so be careful that you get the correct size.
Hi.
I have tried to unscrew the center bolt but the magneto turns with bolt that doesnt unscrew.
What i can do more?.
Piero
 
Is the magneto drive chain in place?

I do not see how the magneto shaft can turn with chain in place, and with AAU on the magneto drive shaft taper.

Caprice?

Keep us informed.

Slick
 
Is the magneto drive chain in place?

I do not see how the magneto shaft can turn with chain in place, and with AAU on the magneto drive shaft taper.

Caprice?

Keep us informed.

Slick

Sorry,
the magneto is in place but without chain, it was cutted off.
Thank you.
Ciao
Piero
 
You must secure the magneto drive shaft by either a new chain, or some by way to restrain the sprocket.

Slick
 
I just took a magneto off an Atlas. As Slick says, the "easy" way is to put bike in gear so that the magneto sprocket is held in place by the magneto chain. If you have already cut the magneto chain I suppose you could wrap it around the sprocket, clamp the ends together with a vise (mole) grip, and then have a helper hold the chain with the vise grip. The worst part of removing the magneto is loosening the bottom magneto holding bolt on the earlier bikes.
 
IThe worst part of removing the magneto is loosening the bottom magneto holding bolt on the earlier bikes.

I finally resigned myself to cut off the open end of a combination Whitworth spanner, and grind the ring end to a thin wall and depth. With this tool, I can get enough arc in the cramped space available. Last time I removed a mag, it was a piece of cake! (Except for draining the oil tank, removing the oil junction block and oil feed lines, then having the residual oil in the timing case leak onto the shop floor overnight !)

Slick
 
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I finally resigned myself to cut off the open end of a combination Whitworth spanner, and grind the ring end to a thin wall and depth. With this tool, I can get enough arc in the cramped space available. Last time I removed a mag, it was a piece of cake! (Except for draining the oil tank, removing the oil junction block and oil feed lines, then having the residual oil in the timing case leak onto the shop floor overnight !)

Slick
Never ending magneto woes. I actually took a file to a Husky metric open end to make a "special" tool. I didn't have the heart to butcher a Whitworth since I am still suffering remorse from unnecessarily flling a perfectly good King Dick to fit one of the head nuts. Some people say the waisted extended bolt from a BSA A10 fits. I'm thinking of trying it although even eyeballing it I'm not sure the bolt will clear the crankcase.
 
Some people say the waisted extended bolt from a BSA A10 fits. I'm thinking of trying it although even eyeballing it I'm not sure the bolt will clear the crankcase.

Scott (Kernel65 on this Forum) has assured me that the BSA long bolt WILL CLEAR the side plates and crank case when used on an Atlas. The tool I described above makes the BSA bolt unnecessary. If you can't get your heart into butchering a beautiful Whitworth spanner, take a worn out 7/16" ring spanner, cut it off as I describe, then with a file or Dremel, open up the "points" a wee bit.

The BSA bolt has the advantage over a Slick-modified ring spanner, in that one does not need to drain the oil tank, remove the oil junction block, and clean up the oil mess on the shop floor.

Slick

PS ....Look at taking a good spanner, and modifying it to ONE particular job, as making a "special" tool, for which we sometimes pay much money for, and value highly. I have the special tool to remove the Smith's Speedo drive nut, and the clutch actuator. Now have the special tool to remove the Maggie bottom nut, as well as other spanners that I modified to allow me to torque those cylinder head bolts, and cylinder to crankcase bolts that cannot be directly accessed by a torque wrench.
 
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Scott (Kernel65 on this Forum) has assured me that the BSA long bolt WILL CLEAR the side plates and crank case when used on an Atlas. The tool I described above makes the BSA bolt unnecessary. If you can't get your heart into butchering a beautiful Whitworth spanner, take a worn out 7/16" ring spanner, cut it off as I describe, then with a file or Dremel, open up the "points" a wee bit.

The BSA bolt has the advantage over a Slick-modified ring spanner, in that one does not need to drain the oil tank, remove the oil junction block, and clean up the oil mess on the shop floor.

Slick

PS ....Look at taking a good spanner, and modifying it to ONE particular job, as making a "special" tool, for which we sometimes pay much money for, and value highly. I have the special tool to remove the Smith's Speedo drive nut, and the clutch actuator. Now have the special tool to remove the Maggie bottom nut, as well as other spanners that I modified to allow me to torque those cylinder head bolts, and cylinder to crankcase bolts that cannot be directly accessed by a torque wrench.
My butchered inexpensive metric werench will remove the.magneto bolt with the junction block in place but it takes over an hour and I probably should ice my left hand when I'm done. FWIW I find that I can get a torque wrench on all of the difficult head bolts with a right angle extension. I use one purchased from Motion Pro. I have seen ones that were home fabricated but I don't have torches so that is beyond my skill rating.
 
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