BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Keith L on 18 Apr, 2024, 16:16

Title: 1946 BSA XB31 Gearbox Problems
Post by: Keith L on 18 Apr, 2024, 16:16
I have two of these early gearboxes and I can't get either working properly on the bike. The one currently installed on the bike is OK in gears 1,2 and three but it won't go into 4th on the road and if I wangle it in with difficulty it is almost impossible to get it back to 3rd gear. All gears select as they should with the bike on the bench and not running so the problem appears to be when the gearbox is under load.

Any suggestions as to what the problem is will be gratefully received.

Keith
Title: Re: 1946 BSA XB31 Gearbox Problems
Post by: idie on 18 Apr, 2024, 17:54
Maybe the linkage needs adjusting, half a turn one way or other might be all it needs. If you remove outer cover the linkage is top tight. Take out the pin and turn the linkage and replace the pin.
Title: Re: 1946 BSA XB31 Gearbox Problems
Post by: DAVE BRADY on 18 Apr, 2024, 18:00
Hi,

A bit of along shot, but chains being too tight can affect the clutch and the gearbox making gear selection difficult.

Dave.
Title: Re: 1946 BSA XB31 Gearbox Problems
Post by: V500 on 19 Apr, 2024, 12:53
As can clutch plates running out of true. Changing fine when the engine is stopped is usually the give-away for this issue.
Title: Re: 1946 BSA XB31 Gearbox Problems
Post by: Keith L on 19 Apr, 2024, 17:59
Thanks for your suggestions. I will let you know how I get on. Keith