Can someone identify this rear hub

[Topdad]

A mate of mine is trying to source a 47 ridgid B31 rear hub he mentioned something about a "thin" spindle type  and a "large" spindle type does any of that make sense to you guys or good you give any ideas as to what he needs to look out for. Oh anyone got one to sell ?

[limeyrob]

I have an idea that the '47 has a fixed spindle like a bicycle wheel that goes into forks on the frame.  The later wheel (49/50?) is the same as the '48 A series with the pull though parallel spindle and holes in the frame.
Here's a rigid wheel on e-bay, but the problems are, it could be M series not B and I suspect the difference is the sprocket which is integral with the drum and hub so its hard to identify.
Given that these are 80 years old most sprockets will be worn so i think it wil be a case of machining off the old teeth and having a ring welded over.
https://www.ebay.co.uk/itm/387618413540?_skw=BSA+B31+rear+wheel&itmmeta=01JD71K6KCZ161DRFZRPW7WG0K&hash=item5a3fdb9be4:g:5Q4AAOSwL6Bl1Qq~&itmprp=enc%3AAQAJAAAA0HoV3kP08IDx%2BKZ9MfhVJKkC9SCXzfuYnrNhlfC4c5xC2q9Ee5Fzt%2FZt0eKBVoNlYpokA%2Bz3vcUVkG4G7RYa2zfEFhWSjEgUIXaWcPUVhN0BKfSQpvitG%2FR2A4jITVVzzsjkqf78rt%2Fv5uBVpg2WGLjaO7uDaZHtGPYnedQRCAueFvnnHH%2BGPvu1JjZla38JAFyB0%2BPnT29v7hQWgUgSK5bG0yTfVzeWZu0VHsBHT3t3W43O79wom2FvhxffAes87zmu8Ko%2FPF3vcyx%2FqzzW%2BCY%3D%7Ctkp%3ABk9SR-LpzOHpZA

[Topdad]

Thanks for that I'm getting him to take pictures cheers Bob 

[Brian]

That wheel on e-bay is the correct one for a 47' B31. I had a B31 and modified the whole axle set up, they have snail cam adjusters and cup/cone bearings. Rather than try to explain what I did I'll add some photos.

[Rex]

Looks the same as my old 1936 Empire Star.

[Swarfcut]

   A bit late to the party, but this may be helpful. Looks like the correct purchase for your bike. Dust cover is missing the outer circular pressing.

   BSA used variants of the crinkle hub design over a long period, but happily the dimensions of the inner centre tube stayed the same, along with the splined drive boss, so a wheel hub from almost any model variant, even unit model range can be adapted to fit using the appropriate bearings, locking rings and spindles. That's how you got the wrong wheel. Plus of course some sellers don't know what they've got.

 Plunger hub has a locking ring each side, both L/H threads. The right side ring is capped by the dust cover, in MAF's example the  circular disc has been removed, the spot welds are still visible. The remainder should "pull off"...no chance in practice  without damage or sacrifice. Back in the day they were readily available, cheap. Not so now.

 S/A models have a single lock ring on the left side, a flatter cover on the right, and the centre tube is shorter, as no space is needed for the absent lock ring. The spindles and bearing spacers are different, so do not interchange between the hubs. But the bearings themselves are the same for both hubs.

  Both hubs use the same  bearing support ring on the left side, (pictured)  described as a thrust washer ....this sets the location of the left side bearing, which then becomes the datum for the whole assembly. On S/A, driving the centre spacer to the right will extract the right side bearing.

  Plunger hub needs the right side locking ring removing before driving out the bearing in a similar manner. Reassemble with left side bearing, followed by the bearing spacer going in from the right side. No need to remove the support ring, but if required it pushes out to the left side in each case. Left lock ring needs to be nice and tight, but right side ring just needs a light nip and a dose of thread lock. Too tight and it loads the bearings axially. On S/A hubs the right bearing outer race finds it's own happy place.

 Solo bike should have 42 teeth on the rear sprocket. 49 means likely ex sidecar bike.

 Swarfy