On Thursday, November 16, 2017 at 10:37:10 AM UTC-8, Joerg wrote:
On 2017-11-15 16:45, John B. wrote:

On Wed, 15 Nov 2017 15:17:28 -0800, Joerg
wrote:

On 2017-11-14 17:31, John B. wrote:


[...]

Anyhow, there are numerous issues here, not the least being that it is
tough to mount a thick rotor so it still lines up correctly. It may be
possible to machine a part to adapt a motorcycle caliper and I have had
parts machined for my MTB. Requires time though. As I said, first I am
going to see if the 8" rotors are good enough which they very well may
be. 6" in back was clearly not adequate.

Good Lord! A disc is just about the simplest thing that you could
design - two circles one inside the other - and almost the simplest
thing to manufacturer. Even in the wilds of California you should be
able to find either a "home machinist" or a commercial shop to make
them to your specifications.


Take a look at a modern MTB, how much available clearance there is and
then think again about your statement.

One way to do it is to machine out some material in the center. And that
requires ... a machine. As I wrote several times now, if the 8" rotors
are good enough then they are good enough. I shall see.


I found a brake that might work for you. https://www.bikerumor.com/2011/09/24...-fiber-rotors/ Skip the CF rotors and go with SS.

-- Jay Beattie.