Originally Posted by
cyccommute
It may be hard to judge the ability brakes when not riding but it isn’t impossible. It helps to have lots and lots and lots of experience with brake systems. After 40+ years of riding and being a mechanic, I happen to have that experience. I can tell from the brake lever feel if the brake is going to be good or bad.
I also happen to have several bikes with both rim, disc and, in one instance, disc front/rim rear. Frankly all of them perform well and will stop me in every situation I’ve encountered from downhills with a loaded touring bike in a downpour to steep off-road riding with the added weight for bikepacking.
Cheap brakes don’t have an “on/off” feel in my experience. Cheap brakes have more of a “is this damned thing going to stop!” feel. Good mechanical disc and good rim brakes work well in my experience and have good modulation. I’ve not had the same experience with hydraulic.
I have good brakes of all the kinds I use. I’ve had what were considered to be good hydraulics and never found them to be all that good. Certainly not worth the hassles that come along with them.
For a long time I had reservations about hydraulic disc brakes since my experiences were pretty mixed. My first hydro brake was a Magura Julie, which was ok. Not great and not really an improvement to the Hayes mechanicals I had. The second one was Magura gustaf, which was pretty incredible in terms of everything. However both brakes had leaks (I bought the bike used) so there was some hassle and loss of braking power. With my mechanical aptitude at the time I moved on to an XC bike which had Avid Elixir 1's. Still good but nothing to write home about. I swapped them for Shimano Deore brakes with the servo wave tech and those were pretty darn good for a while. However they could not cope with the cold of Finnish Lapland and thus were pretty much obliterated and started leaking.
So I went with mechanical disc brakes for a long time. Avid BB7's with compressionless housings in both my touring bike and mountain bikes. Simple and with oodles of power when using the correct rotor size (my tourer has had a 203mm rotor up front and that was pretty nifty).
And now, just recently I got my first fat bike, the Surly ICT. It was a custom build and the shop put in Sram Guide RE's. The difference to anything I've ever used was to put it mildly, absolutely and completely mind blowing. The funny thing with fat bike tires is that you won't exceed the grip they have in almost any summer condition. This in turn means that if you have the power, you can literally stop on a dime. Well the Guide RE's had the power and more. Haven't gone over the bars yet but if I was stupid enough to use two finger braking that'd be a real danger.
Yet I have perfect control. The calipers have four pistons, which alters the brake feel a bit towards the Shimano Servo Wave -feel. They don't bite immediately, yet it's easy to ramp up the braking with very little effort while still maintaining perfect control, and all this with just one finger. Yet these have a lot more power than the Shimano Deore's ever had. These are verifiably in the magura gustaf region of braking power.
I mentioned that there are almost no conditions where the fat tires lose grip, but one place even they trule struggle is a light dusting of gravel over asphalt. But even there I can maintain ABS-esque control with both tires with very little effort as the fine control I get. It really is truly amazing.
It's hard to describe this in such a way that it's understadable so I'll try to go with an analogy. If one has ever tried driving certain US-made sports cars like say, an 80's Chevy Camaro, one knows what bad braking is. Like sure, you can lock up, but it requires your whole leg and then some to do so and you'll really feel the seat springs at your back whilst doing it. Then compare it to a car that has some seriously good braking with ease of use and safety in mind like say, a recent model of a Volvo XC90. The Volvo needs some care with braking as you can stop very quickly with just your big toe, yet it's easy enough to control. That's the difference I get, when I compare the Guide RE's to any type of rim brake and even some discs I've used.
My point is, there are certainly differences in brakes in every category. There are bad disc brakes in both mechanical and hydraulic sides and the bad hydraulic brakes lose to good mechanicals. However IMO all disc brakes beat all rim brakes in terms of, if not everything then at least accuracy and safety. Certain rim brakes have more power but are quite grabby, (V-brakes with really long arms come to mind). And at the end of the day really good hydraulic brakes wipe the floor with any rim brake. Ironically the Guide RE isn't that good a brake. It's middle priced. There are much better offerings available.