Mechanical disc brakes, a frustrated review

I suppose I can say I was a pioneer of disc brakes on road bikes, having bought the first one in December 2009. Ok, it was sold as a cyclocross bike, but the knobbly tyres got immediately replaced with slicks, so it was in practice a road bike. It came with some dreadful Shimano BR 505 calipers, which were not set up very well and I never managed to get to work in a satisfactory way. So I began a journey of upgrades, which I am going to describe here:

Avid BB7: in 2010 they were the must have, but getting hold of the road version was almost impossible, so I settled for the MTB equivalent. Unfortunately, I did not realise the lever throw was meant to be different, hence I had to run the pads so close to the rotor, that any particle of dust trapped between the two caused the well known grinding noise. Getting homogeneous pad wear out of a single piston system also proved tricky. Apart from that, they were much more powerful than the Shimano they replaced and I kept them for a couple of years, until it became obvious that the new “must have” were the Hayes CX5 (then rebranded CX Expert).

Hayes CX5: First impression, they were heavy, I mean very heavy! The pads were kept in place with a magnet, which did seem a good idea, but it wasn’t: it simply meant every time I slid the wheel in and out, the pad got kicked out too. Moreover, as pads wear out, they become less magnetic, something to do with surface rust on the metal part, I would assume. Moreover, seeing magnetisation is temperature dependent, having a magnetic retainer on a part that can easily reach 400 degrees C doesn’t appear a great idea. They never worked particularly well and as a matter of fact, they were a downgrade from the BB7. I don’t know how I managed to keep them for a couple of years, probably for lack of alternatives, which is until TRP became all the rage and the new thing “to have”

TRP HyRD: The first I bought, for the front, was faulty. Meaning it did work fine, but it would not adjust for wear, as a semi-hydraulic caliper is supposed to do. It caused some hairy moments at the Gent-Wevelgem, when I ran out of brakes all of a sudden, luckily it a mostly flat course! Eventually, I got it replaced under warranty and the second they sent me has been flawless and I am still using it nearly three years on. However, it is not a problem free thing: the lever throw is very long and almost unusable with Campagnolo Ergo levers. Marginally better with Shimano, it does really need compressionless brake outer cable, otherwise it feels very spongy. I also never managed to get homogeneous wear out of the pads, it’s almost as if the two independent pistons didn’t have the same hydraulic pressure. With all that in mind, it is a powerful caliper, probably the only one that marginally exceeds a good modern dual pivot rim brake.

TRP Spyre: I bought one for the rear, didn’t want to spend too much for another HyRD and the warranty saga had put me off them. It has been fine, not particularly remarkable, but reliable, even without compressionless outer cable. In truth, probably the only caliper I did not regret buying. You can adjust the pads to suit the lever throw you find comfortable to use.

Juin Tech R1: I bought a set of these, after reading some raving reviews and attracted by the affordable price point. First impression was a lot of thought went into the packaging, but less so in the arm that operates the piston. The fact that when not in tension it has some side play doesn’t feel particularly reassuring. They are semihydraulic, like the TRP HyRD, but they are a closed system, therefore they do not adjust for wear of the pad. You need to adjust for wear using a dial, which is not a huge problem. I never got to trust them going down a big mountain, therefore I fitted them on my commuter bike, where they have been fine, unremarkably fine, they could be better if I invested in some compressionless outer cable, I am sure. Occasionally they seem to stick a bit in the return, but is it the caliper or is it friction in the cable? Hard to tell.

All in all, over eight years I haven’t found what I was looking for and I am now going back to rim brakes on my leisure bike. Of course, I should give full hydraulic a try, but the price point is beyond sensible and has just got worse in the UK since last autumn, when Shimano increased their prices by 20% across the range to compensate for the post-referendum fall of the GBP. I think a pair of 105 level STI with the hydro lines and the calipers retails at 400 GBP or something equally mental. I have STI levers and a pair of 105 rim calipers cost me 50 GBP, thank you very much!

14 thoughts on “Mechanical disc brakes, a frustrated review

  1. Great article! I have a 2013 Salsa Vaya. It came with Avid BB7s. They worked OK until I tried to touch them and then I could never get them dialed in again. Switched to the TRP HY/RD. I was initially really unimpressed, until I swapped the rotors to Shimano Ice Tech, the pads to EBC green and the cables to compressionless. Now it works well, though it sure ended up being an expensive project! The braking is now strong with good modulation, though I agree that the lever throw is too long. It works with SRAM levers, but it pulls very close to the handlebar. I feel like TRP could have refined this system over the last couple of years. They are close.


  2. Hi Paulo. Your ‘journey’ has been almost exactly the same as mine with a 2010 Genesis Croix de Fer (505-BB7-Hy/Rd) – all with similar levels of disappointment. Last autumn, I bit the cost bullet and got some RS785 hydraulics when PX were having one of their silly sales. I now have MTB levels of braking and the original pads are still only half worn after 6 months use (the BB7s used to eat a set every 6 weeks)
    Keep up the good work.

    Liked by 2 people

  3. Well I wish I had not bothered going the disc brake route recently , mine are shimano hydraulic ultegra spec R685 front shifters , the breaking is very good but that’s it , the hoods are rock hard nylon with no padding , no free play adjustment on the brake leavers , only two upshifts for a complete sweep of the outer right shifter , front right inner shifter ratles because of all the free play in the inner leaver(35mm before you get to the shift click) did a 140 k Audax in wales last weekend and got blisters for the first time ever on my hands due to the hoods , not even LEL did that to me , my bikes a Domane and I which I had got the none disc even though I got it for winter/wet weather use.
    I could change to mechanical disc but your comments would put me off that so there as yet is no cheap fix.

    Liked by 1 person

    • Mechanicals will give you grief at the caliper/pad end of the brake, rather than the lever, plus spongy feel if you don’t use compressionless outers. I have gone back to rim brakes in spring, done several long Audax rides and never felt short of brakes


    • I’ve been using the R685 hydraulic shifters for about 8 months now. The braking is indeed awesome (compared to my old TRP HY/RD brakes). When I was setting the brakes up, I noticed that the hydraulic connection at the shifters leaves a big bump that you can feel through the hoods. I thought it would be uncomfortable, but I have to admit that I haven’t really noticed it when riding. Overall, I think the brakes work great, but there’s room for significant improvement in the comfort and aesthetics. The new Ultegra 8000 shifters look like a step in the right direction, but I can’t bring myself to spend even more money to upgrade. FWIW, the SRAM hydraulic shifters I’ve seen at the store some much more comfortable, but I have to admit that I haven’t ridden with them.


  4. Interesting article but slightly disconcerting as I have just ordered a pair of TRP HY/RD calipers to replace the crappy Promax Renders that came with my Cannondale Synapse. These failed almost completely on my last audax just as I was coming down Birdlip hill (1 in 6!).
    I have ordered the TRP’s from an Ebay seller from Taiwan for £75 so if they are not great I guess I can re-sell without too much loss.


    • When they work, they do work well… the lever throw can be an issue with some levers (Campagnolo mainly). Much better with Shimano STIs. I think my first caliper was duff, the replacement did work fine


  5. When I had a fall on my bike last year I ruined one of my Shimano RS Hydro levers….. The look on my face when I saw the replacement price…. Shocking. That being said, as a heavy rider who likes to tackle very large hills, I simply cannot consider anything less. As it is the stock rotors were struggling and getting very very hot, enough the steel was turning a shade of purple and getting tremendous brake fade which meant stopping every 5 minutes to let them cool. I went straight into the closest shop and paid 100 euros for a pair of ultegra ice-tech rotors and those get me down a 1500m descent without fade.

    Liked by 1 person

  6. I have used the Avid BB7’s for years on my road/gravel bikes. They have been great for that. For MTB I used for years and they pretty much sucked.


  7. This is quite late but since this comes up on searches, I want pose a correction for anyone who is disk phobic as this review and some replies are misleading. I also was one of the earliest non MTB adopters of disk brakes, got the first BB7 roads for my cx and commuter bikes the first year came out, but have been quite happy with them and won’t bother with rim brakes any more, disks are just so superior in so many ways, never going back. I think your issue with cable actuated brakes, which you mention a few times, is the need for compressionless housing. Without that, all cable actuated disk brakes will suck. Its that simple. Whether BB7, Spyre, any of the hyro/cable hybrids like TRP hy/RD or Juin R1 (oft sold as Origin8 mech/hyd, Yokozuna Motoko D) etc you need expressionless housing. Now full hydros are the real bomb and I have them on my MTB bikes exclusively. But I like cable for my commuter and touring bikes because road-side adjustments are simpler. I’m on the fence with CX, using Juin R1 mech/hyd for now. But again, never rim brakes for me. I like my hand laced super light wheel rims and my health too much.


  8. I’ve been using Hope disc brakes on one of my road bikes since I had the frame built with appropriate braze-ons in 1999 [last century – purchased before Hope introduced hydraulics]. I’ve never needed to upgrade but now have the problem of not being able to source 152mm [6 inch] rotors. 160mm is closer to 6.5 inches. Anyone have any ideas?


  9. I’ve been using Shimano BR-CX77 for five years with no issues. They are available from a number of online retailers.
    They use a 160mm rotor, and the replacement resin pads are also widely available. These brakes are designed to use standard Shimano levers.


    • Unfortunately 160mm discs, although they are sometimes described as 6 inch, are 4mm [radius] too large to fit my callipers. I’m talking about a frame built before the “big boys” had imposed their standards on the industry.

      Liked by 1 person

  10. I haven’t had any issues whatsoever with my TRP Spyre’s dual piston flat mount brakes. My bike was set up with 180mm rotors on the front and 160 on the rear.


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