Gents
I have a friends Principia Rex (a little old school) with the original hope brakes. The rear rotor has warped and is causing binding issues.
I have tried a 140mm but it catches on the caliper.
I am trying to sort a quick and reasonably cheap solution as the rear brake isn’t the best currently. If I can’t source a rotor then I may try an extension bracket but the older brakes are a little meaty.
Any suggestions??

Ring hope they will bash one out for you.

Don’t know how your 140mm rotor is shaped but should be easy enough for a machinist to turn it down to 135mm

Turning down a 140mm Steel heat treated rotor 5mm ? Aye that’ll be easy without warping it to ****.

Hope should be able to make one. Might not be cheap though.

Sometimes a stack of washers does the job, bit on the frame it won’t be easy. Ask at Retrobikes maybe?

Offroading – turning down a rotor, yep no problem, been there and done it many a time.

Turning down a 140mm Steel heat treated rotor 5mm ?

it’s only 2.5mm all the way round anyway 🙂

I took a 205mm hope disc down to 203 by putting the wheel in some old forks in a vice, then spinning the wheel while holding an angle grinder against the edge of the disc. Kept it nice and round and did the job in no time 🙂

Is it the old 5 bolt rotor? If so, I think I’ve got a 135mm hope rotor you can have…