DropBarFan

Shimano hydros seem, overall, to get better reviews than TRP hydros. TRP Hylex is $250+ (ouch), some folks say there's a fair amount of initial lever travel...deal breaker for me. I like minimal lever travel & it seems like hydros could offer near-zero initial travel if the manufacturers desired. Baffling why Shimano doesn't make non-shifting hydro road levers.

boomhauer

Three years now with Shimano Hydraulic brakes. No problems. City riding and a few tours. I don't think the brakes know if I'm on tour or not. Seems like a pointless discussion.

elcruxio

You seem so sure about that I'm assuming you've taken apart a BB7. So you know about the floating pad contact piece that isn't attached to anything and is thus floating? Piston, contact piece, serves the same purpose. It allows for slight change in pad orientation making better pad contact.

That's not what the CPS washers are for and honestly all mechanic disc brake systems could benefit from them if the caliper mounting surfaces have not been machined to spec after you bough the frame / bike.
Also with BB7 you always align the non moving pad with the rotor since the moving has a floating piece in there which allows for the pad to contact the rotor evenly. If the BB7 has been adjusted properly so that there's almost non perceptible bending of the rotor when brakes are engaged the pads or the disc should not wear unevenly. In all my years of BB7 use have I ever seen an unevenly worn rotor. Maybe if one were to use the soft shimano rotors with metallic pads (which one should not do) could that perhaps happen.
Furthermore BB7's are set and forget until the pads have been worn out. Then you replace the pads and you won't have to touch the caliper. But if you do have to take the caliper off for whatever reason align with the non moving pad because that's what happens automatically if you follow the very simple mounting instructions.
It's true that the BB7 does require a click or two every once in a while to adjust the non moving pad towards the rotor. But to me that's as big of a hassle as using a barrel adjuster to adjust spyres, ie. a complete non issue.

In the case of BB7 it doesn't matter nearly as much whether it has seals on the inside or not. The distance water will have to travel inside a BB7 to reach bearings is longer than with spyres and also less open. I'd also not consider the inside as much of a risk as the outside as there's usually heat evaporating the water getting in. That being said with spyres the inside distance towards the mechanism is shorter than with BB7 and thus a bigger risk. With the spyres the complete mechanism of bearings / sliding surfaces is maybe 2mm from the outside world with a visible gap leading to them with no seals whatsoever. This is on the outside of the brake. So with Spyres there's two viable water ingress ways one of which is extremely viable since it's essentially a gap water can just flow in.
The fixed piston of the BB7 is a bit tight sure, but that's also a blessing since the pad adjuster won't move on its own as with spyre which only uses a flimsy threaded screw.

And did I mention that TRP does not like you taking apart the spyre? Do you carry a full Torx set on tour? I don't. The biggest piece I have is a T30 and the Spyre requires a T40 to do maintenance on. Also a bench vise is recommended. a bb7 opens up with basic tools

As to the spongy disc bendy feel you've experienced with BB7, I wonder whether your BB7's have been properly adjusted. The BB7's I've used (both mountain and road) don't flex the disc all that much since the inside pad rests almost in contact with the rotor so there's maybe 0.1mm of flex when the brake engages. If you search the wide world of the internet the general consensus seems to be that BB7 has a crisp feel whereas the spyre is generally considered to be the spongy brake, which is my experience exactly.


I completely fail to see why this is an issue except maybe in terms of fashion sense. Rotors are also pretty generalized in terms of thickness, but I prefer the thicker ones as they eat more heat than thinner ones.

I suppose feel is subjective. I far prefer the crispness of the BB7 over the sponginess of the spyre.

Trevtassie

Main reason I got rid of the Avids on the front was that they stuck out too much next to the lower front rack mount on the Troll, basically any rack would foul the adjuster without a large spacer, and the adjuster was hard to get too behind the tube on our Duo racks. So I figured bugger it, I'll whack on a Spyke because their profile is lower, and what the hell, $5 extra I can get 180mm discs. Like the BB7, the standard pads that came with the Spykes were junk, I ditched them and put Koolstop semi metallic pads on them. Bonus was I was no longer adjusting either the brakes on my bike or my partners bike any more, I did manage to cook the front, but that was a long slow descent on a 17% footpath, which seems the worst scenario for a disc, low speed, so no air flow over the disc, no aerodynamic braking and no chance to let the disc cool down.

djb

I think it's fair to say that those type of long slow downhills where one needs to brake so much more often, are the worst for great build up with any system. (Other than when attacking at max attack technical downhills with lots of repeated corners and little cool down time)
I've been on fist sized rock downhills like this where you just can't let the bike run, but again, repeated hard braking into a hairpin downhill can over do things also, it's all about detecting the feedback from your braking system and reacting to the beginning of over heating, no matter rim or disc systems.

Trevtassie

Sigh, do you really think that little rubber boot on the BB7 does anything? It has a huge gap where the spring comes out. It's only there so you can't see the spring... you've gotta be grasping at straws to think there is anything functionally different between the degree of waterproofing of these two calipers. They both suck equally.
And the pivoting foot on the moving piston of the BB7 (it's not floating, it can't move back into the caliper of it's own accord) is there because of the inherent design flaw of having a fixed caliper with a fixed piston on one side, it's there to minimise uneven wear in the moving pad because the inner edge of the pad would take all the clamping force. i At the same time, it introduces a secondary issue, because the foot can pivot, it tends to allow the leading edge of that pad to wear faster due to the pad tending to pivot around the pivot from the friction forces from the disc. It's a not insignificant force which can be seen in how the pad is not central over the piston, it's set so the piston is towards the trailing edge by quiet a distance, relatively speaking..This tends to offset the extra force on the leading edge by spreading it over a larger surface area. Despite all this, the pad and disc will wear unevenly,because ultimately the disc is being flexed and the offset piston can't entirely compensate for the varying braking forces applied; it's just physics.
Just as an aside, there is a visible taper on the piston pad of both old brakes I have here and yes, they were adjusted religiously, with the non moving pad kept as close as it could to the disc without dragging.
The Spyke is a good caliper with some clever engineering, especially the thrust bearing. It does have one negative , the adjustment screws could do with something a little more permanent than thread locker . It could be done, probably with an insert that uses the splines of the lever retaining screw as detents. And yeah, the pads wear parallel.

alan s