Those brakes can be excellent so worth getting sorted.
Hi, yes I've had no problem with the 8" brake on other bikes, so its down to the set up. Plan is:
1. Going to get a new decent cable as this one feels too spongy.
2. The shoes only seem to be wearing on the middle section and not at the trailing and leading edges. So am going to try the adhesive emery on the shoes to true to drum first,
3. and then (after I've fitted some better linings) stick the emery to the drum to bed the shoes in.
Any other tips?
Make sure the leading shoe contacts first, a “quick fix” to achieve this is to weld a 1 to 2 mm thick “pad” onto the leading shoe where it contacts the cam and grind it flat. This can transform many duff brakes. Be careful not damage aluminium type shoes doing this.
A design fault of many SLS brakes (like the A10) is the lever being “upside down” so the trailing shoe moves more than the leading shoe (this takes some thought to figure out why, its to do with the distance from the contact point on the cam versus distance from pivot point) so even a well set up brake can degrade over time.
Given the leading shoe gives (say) 80% of the braking effort, if the trailing shoe contacts first, the leading shoe will be prevented from being pushed as hard onto the drum, and the result is usually a poor brake.
Some owners reverse the levers as a permanent mod. It’s a common racing trick.
You can also use emery cloth to line the drum and sand the shoes to fit, whilst a 1mm spacer is temporarily under the trailing cam, so after the spacer is removed the leading shoe contacts first, but I personally have not had as much success with that method as with welding the shoes (and it reduces shoe life!).