BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: Andy Edwards on 27 Jun, 2022, 15:17

Title: A50 Rear Brake
Post by: Andy Edwards on 27 Jun, 2022, 15:17
I wonder if anyone can help with an issue ref the rear brake on my 1962 A50.  The workshop manual and the parts book appear to show the brake shoes fitted differently. Both shoes have the friction lining fitted for about 3/4 of the way around the shoe circumference.
The workshop manual shows the trailing shoe fitted with the lining starting nearest to the cam and the leading shoe fitted with the lining starting about 1/4 of the way from the cam.  This suggests that the trailing shoe will contact the drum first.  The parts book seems to show the shoes fitted the other way around and this is what I would expect to see.

On dismantling the brake I found that it had been assembled wrongly with two of the same shoe! If someone could confirm which of the two scenarios above is correct, I can then decide if I have two leading or two trailing shoes. Thanks.
Title: Re: A50 Rear Brake
Post by: JulianS on 27 Jun, 2022, 15:44
The brake is assembled like this.

Photo shows my A10 rear brake fitted with floating A65 shoes.
Title: Re: A50 Rear Brake
Post by: Andy Edwards on 27 Jun, 2022, 16:14
Thanks Julian.  That confirms that the workshop manual is correct which of course is what should be expected. That means that the brake had been assembled with two trailing shoes!  No wonder it was useless.  Thanks again.