BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Beeza jon on 27 Jun, 2025, 19:24

Title: 51 B31 (rigid) rear hub.
Post by: Beeza jon on 27 Jun, 2025, 19:24
Hi chaps.
Whilst examining the rear wheel of my bike (purchased only a year ago) it appears that I don't have a crinkle QD hub. The bike is an "older restoration " sort of bus and I wonder if the rear hub is from an M series, or were some B31's issued with different rear hubs?

My gratitude in advance for your thoughts.
Title: Re: 51 B31 (rigid) rear hub.
Post by: Derek996 on 28 Jun, 2025, 09:40
That wheel is correct for the rigid frame models. The crinkle QD hub was introduced for the plunger models from 1949.
Title: Re: 51 B31 (rigid) rear hub.
Post by: Beeza jon on 28 Jun, 2025, 10:33
Thanks for that.I had wondered if that might be the case but hadn't been able to discern a definitive point of information. The parts book, workshop manual and owners handbook that I possess are not dated earlier than '55 which makes them very useful....nearly all the time!
The bike appears to be fairly correct for the year (51) but my main priority is its mechanical well being and day to day functionality (as it would have been in the 50's).
Once again, my thanks to you.
Title: Re: 51 B31 (rigid) rear hub.
Post by: Derek996 on 29 Jun, 2025, 11:54
Here is parts list for the 1951-52 models (https://www.dropbox.com/scl/fi/fat4qgv73j1wdkv5462gu/1951_1952_parts_all-models.pdf?rlkey=hk3ayehgx3r41h5brm8b3glz9&st=mcc768nj&dl=0).
Title: Re: 51 B31 (rigid) rear hub.
Post by: Beeza jon on 29 Jun, 2025, 16:07
Thanks for that Derek. I've also had a closer look at my service sheets, and lo! There is a sheet for the rigid rear hub (number 309). I've also chanced upon an illustration in my parts book....(I should have spent a bit more time studying it eh?)
For your help, and causing me to look with more attention, I'm grateful to you.