(Todo: Daniel) BRAKE STANDARDS DRAWINGS
Hey Daniel, just as a reminder that this is still on your to Do list 
No, jokes aside, I have a real question regarding this topic:
I’m designing a Cargo Bike at the moment, and I’m having a bit of trouble with the brake mount at the rear. Iddeally I’d like to use an IS style mount, but the generic IS2000 makes it really hard to land the tab somewhere on the tube with my dropout design.
As the original IS dimensions are for a 140mm disc (or a 160mm disc if you use an IS->PM adapter that usually adds 20mm) and I want a 200mm disc for the heavy bike, I wanted to make it an IS+40mm tab (and then mount the IS→PM adapter for the 200mm disc).
Dimensions are nowhere to be found for that, and just adding 10mm to the radii doesn’t seem to do the trick…
These are the dimensions for the rear IS (140mm) and the front (160mm), any Idea why this is +9,8 for the smaller and +9,2 for the larger radius?
I mean, it’s not much difference to just adding 10, but the fact that it is a different amount just makes me wonder what’s going on…
As an alternative: does anyone have a verified CAD model of a caliper including the IS→PM adapter?
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I don’t have all the answers you seek, but I think that a good step in the right direction is the work that Peter Verdone has done on brake mounts. It’s a little over my head as far as technical drawings go. But for IS mount brakes, my guess would be that the optimal position of the caliper is somewhat dependent on the fact that the rotor passes the caliper mount at an angle and that a direct translation of the mount surface would not have the caliper tangential (or whatever) to the rotor.
Just a guess, but good luck.
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I’ve been deliberately trying to avoid having to read pvd’s very elaborate yet lengthy analysis about everything brake standards… But I guess I’ll have to…
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I use the smallest IS to PM adapter and move the IS tabs up the stay to suit a 200mm (or180mm) disc.
I’ve been planing to do exactly this for a bmx style mtb fork.
My plan was to mount up the IS adapter to the PM brake jig to find the the placement.
If you can track down drawings for the adapters, I’m sure you could reverse engineer it.