Originally Posted by
merlinextraligh
Uhm, disc brakes do not work well as drag brakes. they are not designed for continuous use. The advantage of having a rear disc brake and rear caliper brake is to alternate use to manage heat, not to use one as a drag brake. If you really need a drag brake get a drum.
as for the Spyres, we have used them, as well as TRP hybrids, and full hydraulic.
in order I would prefer full hydraulic, then hybrid then the mechanical spyres.
the hybrids are nice, and a big upgrade from pure cable actuated. But if you can do a full hydraulic setup it is definitely better in raw stopping power, and modulation.
additionally, give the much greater volume of fluid in the full hydraulic setup, the risk of boiling fluid should be lower than In the hybrids which have a small amount of fluid.
I won't argue that a 203mm disc is not an Arai drum, but it is a lot better than most people realize. It's not a best practice, but it is done, and given the scenario being presented, it seemed the better idea than figuring how to 'alternate' between a caliper rear and disk rear. Do people really rig that up? I would be curious how that works in practice. Thing is, drum brakes are no longer easily available. It would be taking a step backwards, I think to try and work one into a modern braking picture.
The main reason why no one has bothered to manufacture a replacement for the Arai drum is that a front/rear pair of 203mm high performance (think Icetech) rotors gripped by modern calipers offers immense performance. And, as the o.p. knows, bigger rotors than 203mm exist, even if I personally have never seen any. Given that, I don't see the need for a caliper at all. I I should have just not mentioned using the disc as a drag. Consider it retracted. And I also agree with the technology/performance ranking you listed, but didn't have time earlier to go into it. A full hydraulic offers a significant advantage over mechanical actuation, the greater fluid volume is neither here nor there IMO because the heat path through the brake lines isn't the most efficient. The long cable run to the rear brake introduces a lot of mechanical friction, even when a lot of the run is exposed. Sticking calipers and/or sluggish action at the rear caliper is eliminated with a hydraulic connection between brake lever and caliper. Prices are coming down all the time on full hydraulics. Brakes that used to cost $600/pr. are now half that. Worth considering.