- Mon Jan 21, 2019 1:52 pm
#81147
First an expectations check. I think this is a brake that will, at best, count as barely adequate for the bike it's fitted to. I have had bikes with worse brakes but it is not very good.
The thing that made most difference to mine was NOT fully tightening the domed brake plate nut so it allows a slight amount of free play on the plate. Up tight then backed of maybe half a turn. This lets it find its own centre/angle.
Have you tried reshaping the brake shoe material to the contour of the drum? Effectively "bedding in" but done in the workshop. Draw a cross-hatching of chalk on the shoes, insert them in the drum and rotate a couple of times holding the brake lever on. The chalk marks will rub off the high points, sand these down with some relatively course sandpaper. Repeat until pretty much all of the chalk marks are gone when you test it. I then file a slight chamfer on the leading edge of each pad to help them cam-on. In theory, this process should finish with your pads radiused correctly. Also, in theory, even if the cam pivots/back plate aren't true and square, it should still work properly because your pad material will all be hitting the drum (if you think about it, BSA and Triumph both fitted their bikes with conical hubs).
The thing that made most difference to mine was NOT fully tightening the domed brake plate nut so it allows a slight amount of free play on the plate. Up tight then backed of maybe half a turn. This lets it find its own centre/angle.
Have you tried reshaping the brake shoe material to the contour of the drum? Effectively "bedding in" but done in the workshop. Draw a cross-hatching of chalk on the shoes, insert them in the drum and rotate a couple of times holding the brake lever on. The chalk marks will rub off the high points, sand these down with some relatively course sandpaper. Repeat until pretty much all of the chalk marks are gone when you test it. I then file a slight chamfer on the leading edge of each pad to help them cam-on. In theory, this process should finish with your pads radiused correctly. Also, in theory, even if the cam pivots/back plate aren't true and square, it should still work properly because your pad material will all be hitting the drum (if you think about it, BSA and Triumph both fitted their bikes with conical hubs).