BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Grandad Russ on 20 Jan, 2021, 16:54

Title: Magneto pinion nut
Post by: Grandad Russ on 20 Jan, 2021, 16:54
Hello all
New member here, some advice needed if poss.
B31 magneto pinion nut required for my build. Two types listed.. Short sleeve and long sleeve. Any advice please on which to order. Ta. 😁
Title: Re: Magneto pinion nut
Post by: Bess on 20 Jan, 2021, 17:39
Hi,
    I can only find 1 nut. Its for years 1937 to 57, part number 24-0195, the other years its a circlip.

Best wishes...
Title: Re: Magneto pinion nut
Post by: JulianS on 20 Jan, 2021, 18:31
Short sleeve and long sleeve nuts usually refer to the central nut which goes into the automatic advance pinion for twin magnetos.

Bess has identified the nut you need which was also used on twin magnetos with manual advance. Image is from the A10 parts book. Ignore the leading number 111 which is just a price code used by the factory.
Title: Re: Magneto pinion nut
Post by: Grandad Russ on 20 Jan, 2021, 19:06
Gotcha, 24 - 195 is what I had written down. I'll order one off Feked tomoz. 😁
Thanks all.
Title: Re: Magneto pinion nut
Post by: Grandad Russ on 20 Jan, 2021, 19:15
Oops, just been on the feked website and they list a short sleeved and a long sleeved nut with the same 24-0195 part number. Really confused now.
Title: Re: Magneto pinion nut
Post by: JulianS on 20 Jan, 2021, 20:02
The Feked nuts are long or short shouldered type, which is what you need.

Not to be confused with the auto advance unit sleeve nut which you can see at the bottom of the photo.
Title: Re: Magneto pinion nut
Post by: Grandad Russ on 20 Jan, 2021, 20:48
Cheers Julian, but which do I need.. Long or short shouldered? Ta. 😁
Title: Re: Magneto pinion nut
Post by: Pete C on 21 Jan, 2021, 05:42
searching on the Draganfly site gives:

24-195  long sleeved nut
24-0195  short  variety.

I have 3 bikes with Magdynos and all have the short version holding the pinion in place.

Title: Re: Magneto pinion nut
Post by: Bess on 21 Jan, 2021, 07:57
Hi,
     I'm believe 24-195 and 24-0195 are the same, however follow the links in Draganfly site, 24-195 on the drawing, 24-0195 on the text?:

https://www.draganfly.co.uk/product-category/bsa/sparesparts-for-bsa-a710-b3133-c101112-m202133/engine-gaskets-gearbox/timing-gear/pre-unit-b-m-group-gear/

Shows short, the image of mine attached demonstrates a small nut will suffice. A longer nut might foul the casing.

To cover all eventualities buy a long one and cut to size.

Best wishes...
Title: Re: Magneto pinion nut
Post by: Pete C on 21 Jan, 2021, 11:07
If you do cut down a long nut (which you don't have to do if you get the correct short one  ;))  make sure it is cut square. I would say a lathe is the best way to do it.
Title: Re: Magneto pinion nut
Post by: Grandad Russ on 22 Jan, 2021, 09:32
Thanks all for the replies, much appreciated.
I've ordered the small sleeve nut from feked. Six quid with p and p. Thanks again all. 😁
Title: Re: Magneto pinion nut
Post by: Pete C on 22 Jan, 2021, 10:17
Now the real fun begins..trying to tighten that nut without disturbing the timing!  :'(
Title: Re: Magneto pinion nut
Post by: Dennis49 on 23 Jan, 2021, 11:17
I find that if you lap the gear to the shaft using fine valve grinding paste and tap the gear onto the shaft when the timing is correct. It should not move. You can also use solvo autosol instead of grinding paste.