- Joined
- Oct 28, 2009
- Messages
- 1,203
Below is a Norton front drum brake upgrade available from Old Britts, as described on their website. I see the logic if you are going to arc your shoes as well. Has anyone done this, did it make a difference, can they recommend this?
Stephen Hill
Spindle Bushing Upgrade:
The stock spindle bore in the backing plate is around .705" and the spindle is around .6673" or .002" under the 17mm (.6693") wheel bearing I.D. The .002" bearing to spindle clearance is what you want to achieve for the backing plate spindle bore. What I am told is that the factory increased the spindle clearance to allow for the brake shoes to self align themselves to the drum, but if the brake shoes are arced to the drum, this extra clearance is not required, and in fact lets the backing plate wobble in the drum, decreasing the efficiency of the brake.
What we do is take some .750" round 6061-T6 aluminum and bore it out to 17mm to make the spindle bushing. We then bore the backing plate spindle bore to around .748 and press the bushing into the backing plate. We then re-bore the bushing to 17mm.
Stephen Hill
Spindle Bushing Upgrade:
The stock spindle bore in the backing plate is around .705" and the spindle is around .6673" or .002" under the 17mm (.6693") wheel bearing I.D. The .002" bearing to spindle clearance is what you want to achieve for the backing plate spindle bore. What I am told is that the factory increased the spindle clearance to allow for the brake shoes to self align themselves to the drum, but if the brake shoes are arced to the drum, this extra clearance is not required, and in fact lets the backing plate wobble in the drum, decreasing the efficiency of the brake.
What we do is take some .750" round 6061-T6 aluminum and bore it out to 17mm to make the spindle bushing. We then bore the backing plate spindle bore to around .748 and press the bushing into the backing plate. We then re-bore the bushing to 17mm.