BSA Owners' Club Workshop Discussions

The BSA Workshop => Pre War => Topic started by: Andy24 on 03 Aug, 2026, 17:45

Title: Gearbox lubrication
Post by: Andy24 on 03 Aug, 2026, 17:45
Hi
Anyone have any advice on the best lubrication for a 1924 roundtank gear box. I've seen varying ideas of semi fluid grease to various grades of oil. Anyone with personal knowledge of which is the better option I'd be grateful.
Thanks
Title: Re: Gearbox lubrication
Post by: Steve.S on 08 Aug, 2026, 03:42
BSA recommended Castrol D140 for the '30s 3 speed gearbox, and I imagine the 2 speed would be the same.
However, if you live in Antarctica you may want to use a lighter oil.
Some people recommend Thixotropic oil, but if you fit a sealed bearing, this shouldn't be necessary.