My Opinion On Disc Brakes

I woke up one day recently, surprised to read that I’d become one of the world’s leading opponents of disc brakes.   Apparently we’re adamantly opposed to them for cyclocross.  Sort of strange that we’d offer a disc brake option on every wheel we build, then, but who knows? The world makes some strange connections sometimes. 

This characterization must come from a blog I wrote nearly two years ago, toward the end of the cx season that I spent using discs.  I’m actually not going to revisit that blog while writing this, since it will be much more fun to have someone call me out on how I re-characterize what I wrote then. 

My issues, as I recall, were:

1.       The power and modulation weren’t substantively more than the best cantilevers, which in my mind are Avid Shorty Ultimates (BB7s were, at the time, the best mechanical option, so comparing best to best was valid).

2.       The dilemma of either having brake rub or loosely adjusted brakes was frustrating to me.  No mechanical brake at the time offered dual-sided engagement, and pad clearance when using road brake calipers was a known issue, so this wasn’t really a rogue impression that I had.

3.       Having a 135-spaced disc wheel in a world of 130-spaced rim brake wheels was inconvenient.

4.       I’d had one instance where my rear brake pad didn’t last through a race.  This was the issue that so many disc-brake users experienced at CX Nationals in Madison last year. 

We were extensively testing discs in 2011.  Many had gone hog wild about how discs were incomparably superior, and would be taking over the world within minutes, yet I was one of maybe 2% of cx racers who were actually using them at the time.  The cocktail of authority and ignorance displayed there has always particularly rankled me, and there was definitely some flavor of “dude, until you’ve actually really tested it, you know nothing, so shut the f up” going on for me.  There was a generally complete dismissal of the real and present shortcomings that I was experiencing. 

I also thought that there were challenges to frame design, not as much with cx frames but with road frames, where the narrow q factors, 400-ish mm chainstays, and 135 spacing wouldn’t play nice together.  At the time, I believe I foresaw 11 speed complicating things, and said that 130mm spacing, plus discs, plus 11 speed, would cause challenges.  At the time, there was no standard over hub spacing, nor disc diameter.  None of these is sorted out, as yet.  People fail to consider disc diameter as an element of frame design.  It’s a big deal. 

So, am I the world’s leading opponent of discs?  I use them exclusively on my mountain bike.  A few weeks ago I had maybe the most fun day on a bike I’ve ever had, at Bryce Resort’s bike park.  Six hours of downhill runs later, my hands had zero fatigue thanks to hydro discs and 180mm rotors.  I’ve said many times that I probably wouldn’t even ride a mountain bike that didn’t have discs.  Hydraulic road brifters have proliferated, (although those brifters are some freaky looking hardware!), and I’d guess they work way way better than the mechanicals I used.  As electronic shifting keeps marching on, the re-decoupling of shifting and braking that I’ve talked about a lot (at least in conversations, if not necessarily in blogs to which I can link), that will offer more latitude for hydraulic lever engineering. 

Following my experience two seasons ago, I went back to cantis for cross, and am still there.  In the fields I race in, I sure don’t see many disc bikes, so I’m not alone in that.  Over time, discs will inevitably dominate, because that’s the way things go.  For now, they’re still a small minority of the bikes I see at cx races.  Top-level US crossers use them, but the top echelon of crossers in the world don’t (van der Haar being a possible exception).  For road racing, it’s a moot point because they aren’t allowed.  For a dedicated gravel or adventure bike, I’d probably prefer discs, but I’d only go hydraulics (maybe those TRP ones with the integrated cable to hydro conversion?). 

For me, the charge of being anti-disc dies on the welcome mat because we offer disc option on every wheel we build.  When my current cross bike dies whatever death is in store for it, I may choose to have a disc bike for my A bike, and I may not.  Until then, if not being a raving evangelist for the undeniable necessity and categorical superiority of discs makes me the world’s leading opponent of them, well, guilty as charged. 

 

Still

Back to blog

12 comments

Mike, I agree that the 140mm trend is dangerous. My concern is that if/when discs are legalized for road racing, there's going to be hell to pay for the neutral support people. I drive a wheel car for road races whenever I get the chance and things are already tricky enough with Shimano 10/11, Campy 10/11, and junior gearing. Now imagine adding discs vs rim brakes to the equation!?!? As for disc size, I was talking to one of the SRAM neutral support guys last month and his prediction was that even if the UCI doesn't regulate disc size, racers will for the most part coalesce around a single disc size just so they can share wheels and whatnot. Given the way the market seems to be going, I'm bummed to say it'll probably be 140s.At the moment, I can fit enough wheels in my tiny hatchback to meet the minimum required to be neutral instead of wheels in-wheels out. I am not looking forward to the day when I need a UHaul truck to meet the same requirement for both braking platforms.

Avi

I hadn't thought about it from the standpoint of neutral support… And it'll get even worse now: Front wheels.Right now, you just swap front wheels. It's not going to be like that within 2 years.The answer, of course, is to swap out the entire bike. You might need 3 sizes of bike and an easy way to adjust seat height.Here's the corner where I hit the deck:https://maps.google.com/maps?q=38.909385,-121.027527&num=1&t=m&z=17(Do a street view… I was going about 40 when I saw the 15 mph sign, and realized I was in big trouble. Completely wore through the tread on a Conti 4000 slowing it down.)

MikeM

Also, the neutral support issue becomes more complicated with the minimal tolerances of disc brakes. I have 3 hub manufacturers on 4 wheelsets. I'm in the process of getting spacers (Syntace makes some), but every time I change wheels there's drag, and I have to adjust. That minor variation in disc location would cause all kinds of problems for neutral support. Luckily my 2 race wheels are the same hub. So, if this is the way we're going, in terms of pro-style neutral support, we'll need some kind of disc mount location (lateral on the hub), disc width, and unused pad depth standard. Otherwise it would be a mess. I would not envy a mechanic in the TdF hanging out of the team car to work on brakes. I kid- those days will be gone, and so will the oooh-my-brakes-are-dragging-push-me-for-2k-I'm-tired scenario! As for the 140/160 standard, I think 140 will become the norm for most road bikes, simply because we'll end up with the "pro" standard. Pros are light (even the heavy ones, comparatively), and they don't get caught in traffic on long descents making them slow to constant braking situation. Heat and pad wear aren't as big an issue. All of that said… I think it will be a little longer before we see them in the pro peloton. Still unnecessary to have super braking power on a road bike in MOST situations. As well, if some have disc and some have caliper, you may end up with more crashes due to some having the ability to slow/stop quicker than others- for that reason I think we'd have to wait until pretty much all teams/sponsors/neutral have them and are ready to make the wholesale switch.

Sean Yeager

It's kind of a silly conversation for most of us. If your goal is to lose 8 seconds on Huez, then go for it.My goal is to stay alive on Mosquito Ridge Road.http://goo.gl/maps/q2XVcYou're either climbing in a big way, or descending in a big way.

MikeM

Maybe things would get complicated enough to where Shimano, Campy and SRAM would agree to a common cassette size, so they all share the same width and spacing.Nah, that'd be too simple. Forget I said anything.

MikeM

Leave a comment

Please note, comments need to be approved before they are published.