Disc Rotor material

Guy Brooke

Hey all, it's been a good few years since I logged in here. I had trouble finding the place now that it's not MBUK forums anymore.

Ok so down to business. I'm making my own rotor as part of a course project, and need to know what grade (if it matters) of stainless steel to use, and the PCD of the basic 6 bolt mount setup. Also I need to find a source of information on how the shape of the rotor affects its performance - i.e whether a wavy surface is genuinely better in dirtier/wetter conditions, and how the drilling affects dirt clearing/cooling etc. I preferably need info from somewhere that isn't a manufacturer's site explaining why they chose a particular shape, but rather a 3rd party source if possible.

Any advice is welcome, thanks.

Guy

ride_whenever

I'd phone up hope, i'm sure they'd like to chat. Also look at performance car discs and motorbike ones, it is all the same technology give or take.

But ones that double up as shuriken are best!

nicklouse

Guy, there are drawings on hayes webby for the BCD link in the sticky above.

Materials there is a topic active at the moment on page 2 http://www.bikeradar.com/forum/viewtopic.php?t=12563211

Guy Brooke

Thanks for that. I'm still looking for a source of info on how the shape/wave of a rotor affects its performance. the hayes "U" section is a bit vague in all aspects.

nicklouse

shape has very little to do with the braking forces other than the larger the contact surface the greater the braking force that can be applied. In a clean environment. TBH though most MTB rotor shapes are more to do with marketing and image. Yes a wavy (patented by magura) can help move crud off the rotors as can the holes. Strange that the discs on the first Gustafs were solid and un vented and round.
Hayes i can not comment on.

Prints

holes help to disperse water in the wet
(why v brake blocks arent solid surfaces but have cuts, to allow the water out)
They also help to prevent heat build.