Originally Posted by
DaleDee
What, a stack of rim brake washers on the caliper bolts because the bolts were too long? And one rim brake washer sandwiched between a caliper and the mounting bracket, so the caliper was cock-eyed? The front brakes on both bikes weren't botched like that. And the Sun bike had an adjustable bracket to prevent the caliper from binding on the rotor. The 'mechanic' apparently couldn't figure that out. The shop owner said they were for adjusting the caliper. I'd like to see how that was done considering Tektro doesn't use or need them.
The photo shows how the washers were used, but not both on the same bike. Two stacks were used on the Specialized, and one was used on the Sun bike. I shorted the bolts to the right length, threw the washers out, and adjusted the Sun mounting bracket and threw the washer away. I'd be interested to hear what Tektro and Specialized would say about the botched brakes.
I hate to get involved in this, but you seem more than a bit misinformed about disc brakes. There are at least 2 manufacturers (Shimano, Sram) that use half-spherical washers in various configurations on their discs. Shimano has not used them recently, but has in the past--to make up for a mounting surface that is not perfectly perpendicular to the bolt hole. SRAM uses them, in general, on many of their brakes (specifically the mechanical discs...). Any good mechanic might shim one/the other post, if the caliper doesn't sit perfectly on the braking track of the disc. The special washers are certainly not specific only to IS brake mounts.
This is all rank speculation, since you haven't posted a picture of your particular setup...