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Contra-rotating brake rotors

Contra-rotating brake rotors

RE: Contra-rotating brake rotors

IMHO, the entire CG stability comparison of motorcycles to cars is backwards. Rotational inertia of the brake rotor pales in comparison to that of the wheel and tire. In a racing environment, the weight penalty and drag will be noticable.

RE: Contra-rotating brake rotors

I may be mistaken but I saw this on Lance Weil(sp)  AKA
Ricky Racer's desk back in 1983 and if I remember the guy had a patent on it then.

One of the advantages was to take away some of the dive inertia from braking. another was to slow down the disk speed.

Anyone remember the model..

I don't know anything but the people that do.

RE: Contra-rotating brake rotors

Any suspension design is based on a model. How accurate that model is depends on how closely the results you get from applying it.

These models are constantly evolving, which is why you constantly see developments in chssis and suspension design.

So, reading the site it seems to me that the model they are using is completely different than the one I use. The bit about the bike going where the front tyre points it is a major discrepancy in the models for a start.

All that aside, having the brkes connected to the wheel by a gear train, isn't something that appeals to me for a start!

The other problem I have with this is that since when have motorcycles been hard to turn?

I'm also going to try and remember to weigh a sport bike wheel and discs on Monday.....

RE: Contra-rotating brake rotors

Slowing a brake down is like lowering voltage, everything gets heavier.

For the rear, a few bikes have had a small disc brake at the countershaft sprocket. Very efficient, but rarely a nice fit.

RE: Contra-rotating brake rotors


Only bikes I've ever seen with brakes on the the drive sprocket, were Fred Kodlin's friction drive V-Rod and Mike Puglisi's (I think) biker build off friction drive bike.

Since you've got a reduction on the final drive, the brake disc has to spin faster than the wheel, and because you tend to get packaing issues with the available space it often has to be quite small. All of which adds up to a less effective rear brake.

And again it's connected to the wheel that it's braking by a drive train and one that's quite prone to slop. All of which sounds like a recipe for a "snatchy" brake to me.

RE: Contra-rotating brake rotors

I agree with Fabrico and I was thinking at the time that it was adding unsprung weight and  I knew gear lash would be a problem.

I was working on a anti-dive system myself at that time and that is the only reason I gave it a second look.

Now I never hear any concerns about anti-dive.


I don't know anything but the people that do.

RE: Contra-rotating brake rotors

Sounds like a technology looking for a purpose to me.

What about the wear that will build up in the system, increase in unsprung weight, potential for breakages?

Also what is the relevance of the video on the website. A motorcycle going around a corner. How can you or I tell if it handles any better? Was it even fitted with the contra rotating brake system?

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