Stuff We Like: Cable-Actuated Disc Brakes

Avid BB5 Cable-Actuated Disc Brake

While I prefer the aesthetics of a delicate, high profile cantilever or a classic, dual-pivot caliper, I have to admit that nothing quite beats the overall performance of a high-quality, cable-actuated disc brake (also known as “mechanical” disc brakes). Drum/roller brakes are heavy and generally provide only mediocre braking performance, and most every other type of performance brake uses the rim wall for a braking surface, a fact that guarantees your rims will be toast long before your hubs go. Rim brakes can sometimes be poor performers in wet conditions, they make an awful mess in the rain, and the caliper variety rarely provide sufficient clearance for robust tires and fenders. Hydraulic discs are typically more powerful than mechanical discs, but the difficulties associated with cutting fluid lines and bleeding brake systems are not a fair trade for their slightly better performance over their easier to set-up and maintain cousins. A high-quality mechanical disc brake such as the Avid BB7 combines the simplicity and user-friendliness of cable actuation, with excellent all weather performance and long-term, wheel-friendly reliability. Setting aside aesthetic considerations and tradition, cable-actuated discs are hard to beat from the standpoint of pure functionality.

Avid Cable-Actuated Disc Brakes

47 Responses to “Stuff We Like: Cable-Actuated Disc Brakes”

  • Aaron Pailthorp says:

    Given that I didn’t have to cut or bleed the hydraulic brake lines on my bike, I have to say I really like them. I hadn’t even heard of disc brakes until I went shopping for a new bike about a year ago, and ended up with a set on a new bike. I really like how delicately the fluid allows modulation of the brakes. I’ve only test ridden cable disc brakes a few times, but I’m sure I could instantly feel the difference in a blind test. The cables just feel more mechanical, and have a small amount of tension that must be put into the cable to get work done. The hydraulics have none of this stickiness. The hoses once installed are lower maintenance than cables; they never need to be tightened.

    But again, that’s from the perspective of someone who has never had to install a set that wasn’t “pre-bled” and cut to length already.

    I did end up swapping out some really really cheap “Quad” brand single piston (!) hydraulics for some still pretty cheap Shimano dual pistons I got off ebay (lots of take offs available), but the hose lengths were fine, and the installation really couldn’t have been easier.

    Thanks for the review.

  • Alan says:

    I agree, Aaron, nothing feels like a well set-up hydraulic disc brake, particularly on the rear wheel.

    The action of mechanical discs varies quite dramatically from one model/brand to another, and a top-end mechanical like the BB7, combined with high-end cables and housing, approaches, but doesn’t quite match, the performance of hydraulics.

    Regards,
    Alan

  • Brian C says:

    We have 2 bikes with disc brakes – actually one catrike pocket with avid mechanicals, and a hybrid with hydraulic brakes (which have been completely trouble free now into their second year). I love both of these in the winter – when we get lots of rain to contend with.

    I am now looking for a mixte bike for my wife, and would love to have it with disc brakes, but none of the ones I am looking at (Rivendell’s Betty Foy, Soma Buena Vista) seem to have these as an option. (also means my own dream of adding a Civia Bryant to my inventory is on hold for another year at least, sigh – like the idea of belt drive and disc brakes for contending with wet weather).

  • Logan says:

    Russ Roca of pathlesspedaled.com mentioned the only thing he didn’t like about disc brakes were the difficulty of seeing how much wear was on the braking “pad”. I think it may have been too much wear on his bilenky front disc pads that resulted in a spring break down on one of his weekend bike tours last spring. http://epicureancyclist.com/?p=304

  • Doug P says:

    I used to think disc brakes were needlessly complex for a bicycle, but my recent research tell me disc brakes, especially the Avid BB7, are well-loved, so, why not! The price is similar to high-end V-brakes, and the problems Alan mentioned inherent to rim brakes merit a good look at discs. Clydesdales doing downhill will logically prefer hydraulic, but for most of a correctly set up cable disc setup should work fine. My next mountain or cross bike will sport discs. ‘Nuff said.

  • Alan says:

    “I am now looking for a mixte bike for my wife, and would love to have it with disc brakes, but none of the ones I am looking at (Rivendell’s Betty Foy, Soma Buena Vista) seem to have these as an option. “

    Mike Flanigan at ANT has built some sweet step-throughs and Mixtes with discs…

    http://antbikemike.files.wordpress.com/2008/11/light-roadster-2009-105.jpg

    Alan

  • jamesmallon says:

    I have always eschewed disc brakes as needlessly complex, but I think I now see their merits. For one thing, it is often a pain getting fenders to fit between a tire and calipers, or even cantis. I like how the disc brakes on the Norco Vesta makes short work of that.
    http://norco.com/bikes/urban/belt-drive/vesta/

  • John says:

    There’s also a step through version of the Raleigh Superbe Roadster

    http://www.raleighusa.com/bikes/hybrid/superbe-roadster/

  • Roland Smith says:

    The only problem I’ve had with hydraulic brakes since I started using them exlusuvely in 1998 is that one of my brake lines started leaking after having been rubbed agains the frame for over a decade. Fitting a new line and bleeding the brake wasn’t difficult.

    Apart from that the only maintenance I’ve had to do was replacing brakepads (which can usually be done without even removing the wheel).

    No cable adjustments or cable lubrication necessary. And unlike bowden cables, hydraulic lines don’t freeze in winter.

    And nothing beats the rock-solid feel and control of hydraulic brakes! After getting used to the hydraulic disc brakes, I consider every other type of brake inferior.

  • Alan says:

    Hi Logan,

    The method is different for each manufacturer, but Avid brakes have an indicator built into the adjustment knob to alert the rider when the pads need replacing. This is from the manual:

    “Over time, you will need to compensate for brake pad wear. You can do so with two very simple adjustments: Turn both the inboard and outboard red adjusting knobs clockwise one or two clicks as needed to restore your brake to optimum settings. DO NOT use your barrel adjuster to compensate for pad wear. A pad wear indicator is at the center of each knob. As the knob is turned in, the indicator will retract deeper into the knob giving a visual indication of approximately how much the pads have worn.”

    This seems to be an effective system.

    Regards,
    Alan

  • Charlie says:

    I agree with Alan and went to quite a bit of trouble to outfit one of my commuter bikes with a front disc (Avid BB7). But I recently learned that not all roller brakes are created equal. Link from my name is from a Dutch cargo bike company reporting that Shimano IM70 and IM80 roller brakes have “a more consistent, snappy feel and [are] more powerful” than the IM40 and IM50. I’ve only used the IM40. Anyone know if there are bikes in the US that come with the IM70 stock?

  • Dustin S. says:

    Hi Alan,
    Just curious: Does your opinion of mechanical disc brakes vary depending on the type of riding one is doing? I am in the market for a touring bike and have heard from many that cantis are usually favored over disc brakes on this style of bicycle.

    Thanks,

    Dustin

  • Alan says:

    @Dustin

    For the most part, the issues are the same regardless of whether you’re commuting or touring, but there are a few things to consider.

    –Disc brakes place bigger stresses on front forks than cantilevers, so frame designers have to take that into account when designing touring bikes where the loads are typically greater than for commuting. This can result in a stiffer fork which may produce a more harsh ride.

    –Generic brake pads are easier to find than disc pads, though that’s less of an issue than even just a few years ago (most people will carry their own pads on a tour anyway).

    –Discs require a dished front wheel, so theoretically the wheel is not as strong. This is probably a moot point on a well-built wheel though.

    –Racks and fenders can be harder to mount on a bike equipped with discs, though a purpose-built touring bike with discs will usually have braze-ons and eyelets strategically placed to work around the disc mounts.

    There are a number of high-end, purpose-built touring bikes outfitted with discs (Tout Terrain, Co-Motion, etc.), so certainly they are a viable option if integrated into the bike design from the get-go.

    For more on this, check out this article by Sheldon Brown that was published in Adventure Cycling Magazine:

    https://www.adventurecycling.org/resources/Brown_MechanicalAdvantage_Brakes.pdf

    Sheldon essentially said any high-quality brake will do for touring, each has its advantages and disadvantages, and don’t let the brakes be a deal killer if you find a bike you like.

    Regards,
    Alan

  • RMH says:

    It’s the weight and stiffness “penalties” that have kept me clear of disc brakes and the kind of forks needed to mount them on. I also ride mostly fixed gear in the city, so I’m really not using my rim brakes much, if at all. Franky, I find disc brakes fugly compared with the elegance of a classic high profile cantilever brake on a slender, gracefully curved fork. But, it’s hard to argue that there’s anything better than discs for stopping the bike when it really needs to be stopped fast.

  • doug says:

    I love the Avid BB7. A fabulous cable disc brake. Set up, adjustment, and maintenance is intuitive and relatively pain free. Much easier than a canti IMHO. Also, I think these brakes can look quite elegant on an urban commuter. Over the past 3 years, I’ve ran the BB7 plus Avid Speed Dial levers on a MTB commuter with baskets, fenders, etc., totaling about 45lbs; with, a cargo trailer hauling over 100lbs, and have found the braking performance to be quite superb in sun, rain, and snow conditions. ‘Guess I’m a fan. :-)

  • Jeff says:

    “Setting aside aesthetic considerations and tradition”….if only I could get past how they look, which, at least for me, is clunky. I’d never argue against their performance but I can’t imagine buying a bike with disc brakes either, at least not in the foreseeable future.

    Thanks for the great write-up Alan.

    - Jeff

  • Alan says:

    Hi Jeff,

    I don’t mind how they look on some bikes. For example, they seem like a good fit for the Loring…

    Regards,
    Alan

  • Tim D. says:

    I don’t ride super expensive rims, so having to relace a wheel every so often doesn’t bother me. However, my dream touring bike would be spec’d with disc brakes. I like the idea of not exploding a worn rim on a steep descent loaded down with 100 lbs. of gear. I’m actually thinking about buying a new fork with disc tabs and using a front disc on my commuter bike, just to give it a try.

  • Androo says:

    I’ve never had a bike with discs, but have test ridden some – low-end mech. disks are worse than decent V-brakes, but good mechs or hydraulics are really stellar. As far as aesthetics go, my tastes in bikes have never been constrained by tradition, so I think they can look great on certain bikes. Superior, even, to rim brakes.

    @ Dustin

    Personally, I think cantilevers don’t really have much place in the bicycle world anymore. The reason that they are ostensibly better for touring is because they offer more rim clearance, allowing you to limp somewhere if you break a spoke and your wheel is badly out of true – in practice, modern spokes and wheels are so good that this rarely happens. The only other issue is one of compatibility, because few road levers have the right cable-pull for V-brakes (which have much better modulation, stopping power, and ease of maintenance and adjustment compared to cantis). The only reason they are still used in cyclocross racing is because the UCI banned discs, so manufacturers have less incentive to develop good road-style discs. I think eventually the writing may even be on the wall for road bikes, but then again, tradition is a powerful force…

  • Russel Haynes says:

    I was a little frustrated with figuring out how much pad was left on disc brakes but I noticed something a few days back. When I squeeze my brake brake lever, the actuator lever on the brake goes almost all the way to the cable stop – maybe I could add some shims if there is some pad left but I think I’ll just replace the pad, now.

  • jimbo says:

    I have been riding a Raleigh Sojeorn for about two years and the brakes are good. The rear is a little spongy at times but, this bike is ridden every day to work rain, sleet, or snow like today. I really should replace the pads some time. Anyhow this bike is a little heavy by race bike standards but probably average for touring bikes. The rear rack is standard so no issues there on the front I have a Jandd rack and had to bend the lower tab a bit to fit because of the brake. Since the popularity of 29er’s I bought a second set of wheels cheap for the snow tyres. Swapping wheels does require a quick pad adjustment as they are mabey a mm different. So after a couple of years and really abusing this bike I am totaly sold on disks for touring and commuting.

  • dynaryder says:

    My first winter commuting,I glanced off a car’s fender because my V brakes had packed up with snow. This combined with the freqency with which I was replacing pads and limping home one night with a wobbly front wheel after a pothole encounter convinced me that my next commuter would have discs. Now the only bikes in my fleet that don’t have discs are my two road bikes and my folder. All weather stopping,long pad life,easy/infrequent adjustments,cleaner wheels,not worrying about perfectly true rims,and never having to remember(or forget) to reconnect the brake after wheel removal have convinced me that disc brakes are one of the best things to happen to bikes. As for esthetics,I’ve ridden motorcycles my whole life,so I like the way discs look.

    @Russel: do not shim your pads. This is a Bad Idea. If you want to check for wear,just look straight down into the caliper and apply the brake(if you can’t reach the lever just move the caliper’s arm). The pads should move enough that you can see how much material is left. If not,pull the wheel and repeat,the pads will be easy to see.

  • Dolan Halbrook says:

    I have a set of BB7s on my touring/commuting rig, and they’ve been pretty solid over the past two years. Brake feel is fine, a bit of squeal here and there, but nothing big. Changing pads wasn’t as easy as I expected, but not extremely painful, and it took me over a year to go through the first set, and I brake HARD at times.

    That said, I have a set of V-brakes with Kool-Stop Tectonic cartridge pads on my Xtra, and I have to admit, the performance __even in the wet__ is pretty darn close to the BB7s. The bonus is that they’re much lighter, and it’s much easier to find non-disc wheels than disc wheels.

    At this point I’m thinking of building up a fairly light commuter and I’m on the fence. I’m in PDX, where it rains a fair bit, so stopping power is an issue. Do I favor price and weight or low maintenance? I think in the meantime I’m going to see how the Tectonics hold up wear wise?

  • doug in seattle. says:

    I have cantis on my camping bike. Tektro 720s up front and Oryx in back. Overall I can’t complain — they’ve stopped my substantial mass + full touring load in the rain on muddy roads many times with no problems. I do tend to ride slowly in inclement weather, however.

    I guess I might say the disadvantages of rim brakes are often overstated. It often reminds me of SS/fixed people moaning about how hard it is to maintain multispeed drivetrains. Modern brakes of every design are just really, really good across the board.

  • Charlie says:

    Yes, as far as stopping well lots of brakes work. But on a daily-use bike, the rim wear is at least unfortunate and the black muck generated by wet-weather braking is unpleasant if not an actual problem that needs to be solved.

    One other solution is ceramic rims. They solve both of those problems, and they improve wet-weather braking.

    Charlie

  • Scott Wayland says:

    Love discs–Avid only, please.

    But does anyone have a fix for the squeaky? On one bike, despite fresh pads–and even a fresh rotor–the front brake squeaks. The rear–dead silent. What gives? One fellow suggested electrical contact cleaner from the auto parts store, which I have yet to try. Alan, anyone, help!

    Thanks.

    Scott

  • Dave says:

    Alan,

    I agree 100%. Cable-activated discs, specifically Avid’s BB-7, are great. Hydraulics are only a necessity on mountain bikes, where the longer, steeper grades and loose surfaces make brake-fade an issue.

    Around town and on the road mechanicals are fantastic.

    In touring applications you have the added benefit of being able to carry out roadside repairs…something to consider if you’re riding unsupported across the country!

  • Alan says:

    @Scott

    “But does anyone have a fix for the squeaky?”

    Hmmm. Brake squeal is usually related to high frequency vibration which is most frequently caused by loose parts. I’d check to make sure everything is snugged down properly (rotor and caliper body) before trying cleaners/preps.

    There’s a possibility the fork itelf is flexing, introducing vibration into the system. This is fairly common with V-Brake/Canti mounts and I wonder if it’s an issue with your particular fork’s disc mount. Was the brake squealing before you replaced the rotor and pads?

    Alan

  • DrMekon says:

    I am glad you said roller brakes “generally” provide mediocre braking performance. We’ve had 3 bikes with rollers, and 2 were mediocre. However, my wife is currently running a BSP Seine mummybike, and the braking is amazing. You can easily lock the wheels, but the braking is still very progressive. I’ve spoken to the distributor about it, and he thinks they’ve incorrectly specced higher ration levers, but isn’t certain. Whatever they’ve done, ITSM that rollers can do better, and that they don’t need looking after makes them ideal for commuter bikes if they can be made to work better.

  • David says:

    My LBS seems to have a philosphical problem with discs on road bikes, with one of their issues being that the disc tends to wipe at some point during each revolution so there’s never truly “silent running”. In my (limited) experience and talking to friends with disc-equipped bikes, this doesn’t seem to be the case. How about the folks here?

  • Alan says:

    @David

    I’ve been able to make every disc-equipped bike I’ve owned run silently. There’s no reason that a properly adjusted, high-quality brake with a straight rotor shouldn’t run perfectly silent.

    Alan

  • John Boyer says:

    I use the Civia Loring for Hot Italian Pizza delivery because of its disc brakes and nimbleness in traffic. The combination with 3 speed internal hub makes for getting from A to B with the least amount of thought and effort thus being able to focus on traffic, timing and potholes.

    Simply said Its a pure joy to ride with alot on your mind.

  • Scott Wayland says:

    @Alan: I’m pretty sure everything is tight, but I will go back and check. The brake has always squeaked. When I put on new pads, there’s a brief period when it’s pretty quiet, but before long, the squeal sets in. The fork is amazingly beefy, heavier than other forks I’ve had that did not result in brake noise. It’s dang frustrating.

    Scott

  • Charlie says:

    Dr. Mekon,

    Thanks for that note on the roller brake performing well. Based on the posting I quoted above (and is linked again from my name), I’d bet that it has an IM70 roller brake instead of an IM40 or IM50. I’m not sure if it’s easy to read that off the hub but perhaps you can identify it based on the pictures you get by googling shimano IM70 and shimano IM50. (the IM70 has a black center vs. the silver center in the IM50).

  • Aaron Pailthorp says:

    I’ve had less noise with the aftermarket Kool Stop pads I’m using now. It might help to recenter the calipers by loosening the securing bolts so it can move side to side, then closing it with the lever, and re-tightening the securing bolts (tightly) while holding the caliper closed.

    I’ve got the cheapest Shimano takes offs I could find on ebay, and I haven’t really had to spend any time fiddling with them, unlike the single piston hydraulic brakes that preceded them. I think the cable discs I’m planning on replacing with likewise on a new bike I have on the way (Norco Ceres!) are also single action. Maybe single action are inherently more noisy? Are some cable discs single and some double action?

  • David says:

    Thanks Alan. As I said, I think it’s more of a “philosophical” problem on the part of the LBS, R&E Cycles. I was a bit surprised by this as rainy Seattle is where the advantages of discs for commuting are most apparent. Then again, they don’t really cater to the commuter (more tandems, racers, and tourers) and they do make and market their own cantilever brake design, so there’s the potential for a conflict of interest.

  • Don says:

    I have commuted and toured year around here in the rainy PNW for over 30 years. The bikes I use in the fall, winter and spring either have cantilevers or center pulls. My commute route has multiple oppurtunities for stops or slowing at the bottom of significant hills. I am anal about maintaining my brakes, i.e. pad replacement, rim inspection, etc. I am also more cautious when it’s dark and wet even on roads I have travelled over literally hundreds of times. In all these years I can’t think of any incidences where a loss of braking has caused me to fall or run into anything. Maybe I’m just lucky, but in my opinion, well maintained brakes of decent quality and common sense are more important than the style of brakes used.

  • David says:

    Don, I don’t disagree. I keep my caliper brakes in top shape and my wheels true to +/- 1mm, so my braking is fine. However, I’ve gone through two rims in the last couple thousand miles, each of which required a ~$175 wheel rebuild, not to mention the hazard and hassle that goes with that kind of failure. I’ve therefore vowed that my next bike will have discs.

  • Don says:

    I too have rebuilt wheels but not at that rate, I generally use heavier touring rims suc as the Velocity Synergy or the Mavic A319. These have a thicker sidewall and and seem to last quite a bit longer than lighter rims.

  • Fergie348 says:

    I disagree that cable pull disc brakes are more powerful than a good set of canti’s in dry conditions. I’ve got a set of Avid BB-7s on my commuter where I used to have a set of old XT cantilevers. I think the cantis with good pads, in clean and dry conditions were actually better at stopping the bike quickly. Add some mud or water or both and the story changes quickly. I’m now dreaming about a relatively weatherproof and completely capable commuter/touring bike built around a belt driven Alfine 11 setup with Avid BB-7 discs, fenders, racks and a generator hub. Probably a bit heavy, but go anywhere and no cleanup will make things nice on my regular commute.

    One thing to note – the Avid BB-5 and Avid BB-7 are identical except for one very important feature that the 7 has but not the 5. The BB-7 has two adjustable braking surfaces and the BB-5 only allows adjustment of the outer pad placement. I don’t know how you adjust a BB-5 to avoid disc rub after the pads wear in. It may be a bit more money, but get the BB-7 if it’s at all possible.

  • Alan says:

    @Fergie348

    I agree; go for the BB7s if you have the option. That said, I’ve had pretty good luck with BB5s, but you have to replace the pads a little sooner.

    Alan

  • Logan says:

    Hey Alan,

    Have you read the article on this topic in the latest Bicycle Quarterly? JH has an interesting perspective and compares bike wheels and braking to trends in the engineering of car wheels and braking. Its a short article and I wish JH would have gone into why hydraulic braking systems are different in performance than cable systems. ;)

  • Alan says:

    Hey Logan,

    Unfortunately, no, I haven’t seen the article. I’m quietly boycotting BQ until JH makes available an electronic subscription. :(

    Thanks for the heads up!

    Alan

  • jimbo says:

    The artical , Why cable-operated disk brakes dont work well, I think gets a little side tracked with the car braking systems brought up. What is right about the artical is the problem with the brakes is the housing compressing. That is why on my Sojourn rear brakes feel mushy and my Hydraulic brakes on the 29er don’t as there is no compressing of the cable. That being said this seems to only affect the rear as it is a much longer cable the front feels fine. The hydraulic systems use pressure so the only effect on them is the type of hose used. His last statement of the artical is spot on we need a hydraulic system for drop bars!

  • Alan says:

    @jimbo

    Can you clarify, is he saying housing compression is a particular issue on disc brakes? My experience is that housing compression has a negative effect of braking regardless of what type of brake it is. The issue is particularly noticeable on tandems and recumbents with their long cable runs to the rear wheel. “Compression-free” housing like Jagwire Ripcord (not to be confused with “compressionless” shifter housing) is certainly an improvement over standard housing, though I agree, there’s nothing as good as a hydraulic line to the rear brake.

    Alan

  • jimbo says:

    Yep, housing compression. I have BB-5′s and BB-7′s on 26 inch wheeled mountain bikes and havn’t noticed the same feel. I just looked at the Raleigh and the housing is not Jagwire and the other two bikes are. This may be the differance in feel. I will change the Raleigh when I get a chance and let you know. Might take awhile I am really lazy!

  • DavoColo says:

    I have some high-end Avid Juicy Ultimate Carbons on one MTB and Avid BB-7s with Speed Dial levers on my other. Admittedly, the hydraulics are better modulated and more powerful for any particular amount of force on the levers … but triple the cost.

    As long as you go with high-end mechanical brakes — BB-7s are really the class of the field here — you’ll enjoy them a lot. They’re far easier to adjust than hydraulics and infinitely easier to set up (anyone can install and maintain a cable-brake system; I’m pretty handy but I leave cutting, bleeding, and filling of hydraulic lines to my LBS).

    The best thing about hydraulics: Amazing stopping power.
    The worst thing about hydraulics: Hoses filled with oil — which will eventually escape one way or another.

    The best thing about mechanicals: Normal humans can maintain them.
    The worst thing about mechanicals: Okay, they’re a little less elegant and powerful than hydraulics.

    The best thing about having both Juicys and BB-7s: They take the same brake shoes, so I don’t have to buy more than one type.

 
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