Bicycle Mechanics - disc vs caliper

I understand that disc brakes are more reliable than caliper brakes and more expensive, but do they require more or less maintenance?

It bothers me that I have to keep adjusting my brake pads to keep me braking, I dont mind that much but if I can avoid it with disc-brakes that would be nice.

Most disc brakes, porbably all are self adjusting...I remember atleast over 5 years ago i had a mtn bike with mechanical shimano disc brakes, which probably weren't the most exspensive to boot, but i went thru a pad without a single adjustment. Hydraulics...unless something changed yield longer pad life due to the ability to use harder brake pads. Hope that helps.

Hmm so thats good, I am a commuter and dont really care for performance, does anyone think disc-brakes are overkill?
I live in a hilly-rainy part of ontario.

Disc brakes do generally require less maintenance, but it's not that they're self adjusting, they just have thinner pads and move less to brake, so they seem to stay in adjustment for longer... also they don't rely on your rim being true so you can use less clearance between the pads and the rotor.

I've been commuting with some BB7s for a few months and love that they brake better in wet and muddy conditions, that they have more overall stopping power, and that they're cleaner (you don't end up with rubber-dust covered rims), but there are some requirements that often get in the way of using them:
You must have a frame and fork with disc brake mounts
You must have hubs with rotor mounts
You must be using long-pull style road levers, mountain V brake levers, or included hydraulic levers - so if you're running an average road bike, you'd be spending hundreds of dollars plus the cost of brakes to get all the bits associated with using them.


If you've already got mounts, disc hubs, and long pull levers, a set of disc brakes will run you less than $100 for decent mechanical ones and does have some considerable advantages.

yeah i wouldnt be converting my roady to disc brakes, just in the future if i get a new bike i think i'll get one with disc brakes.

EDIT: I guess having disc brakes would make people want to steal it more.

Definitely get discs. The mechnical disc brakes on my new Novara Big Buzz are really great...alot less trouble than calipers. The only adjustment I've made is to the inboard pad when it is found rubbing on the disc. Stopping power will throw you over the handlebars so wear your knee pads. :)

If you do get discs, get BB7s. Really simple set up, and no tools adjustment.

I don't understand why you have to adjust your rim calipers so much. Yes, they do require periodic adjusting, but on all my rim calipers that means about 1.5 times per year.

I also have a disc brake commuter. In dry conditions it's no better. In wet it is better, though not exponentially. Keep in mind that with the typical rim brake you can already overcome the traction of the tire...more powerful braking will still leave you skidding.

I like my discs though, they're nice, and fairly simple after setup is complete. I'll play devil's advocate on this and recommend Shimano R-550 (or was it R-500?) road discs over BB7 road discs. There's less play in the mounting system, which means they don't squeal under conditions that the BB7s do. (I used to run BB7s.) The return spring is much more powerful and positive, ensuring pad retraction every time; this is especially important with the rear brake since it has more cable to drag back into the "relaxed" position.

The adjustment dials on the BB7 are supposed to be "tool free" and easy to use by hand, but from the start required my needle-nose pliers...more so after road grit started getting on them. The Shimano system requires a 3mm allen, which is smaller than pliers, and much easier to turn as well.

How good are discs in the rain? My calipers suck when wet.

The advantage of discs is greatest in the wet, in dry conditions a rim brake works very well.

IMO mechanical disc brakes like the BB7 are fairly maintenance free aside from an occasional change of cable housing; they do require manual pad adjustment for wear. I've run some of mine for almost 9 years without a caliper overhaul. The BB7 is a bit easier to setup initially and easier to adjust. Hydraulic discs, while self adjusting for pad wear, require a bit more attention at setup, as well as a bit trickier maintenance in terms of bleeding lines and sticky pistons (and the tools/supplies needed). Either type of disc is really no worse maintenance wise in the long run once you're setup for taking care of your gear (let alone having someone else do it for you).

Try out some Shimano Hydraulics and you'll never go back. The available modulation and stopping power on these truly make riding more enjoyable. Hardware will only get lighter with time, so look for this stuff to begin appearing more on road-oriented rides.

They're low maintenance with one caveat: quick release wheels and pesky lawyer lips. Due to the tight clearances between the pads and the disc, if you remove your wheels and don't re-tighten your quick-release exactly right, you might end up some rubbing. Short answer: set it once and keep your wheels on. Also, if you ever need to re-adjust, keep a couple pieces of business-card thickness paper or cut playing cards around to use as shims. This will get you dialed in perfectly.

When I bought a new bike last year I specified claipers because I didnt want the weight penalty when going up hills (and the extra cost. Its not only the weight of the brake units, but the wheels and forks are also heavier. The rear disk can provide problems with attaching a rack. Since the rear brake is only a back-up system you could consider a front disk only. Recent calipers with pads mounted with spherical washers and nuts are much easier to adjust than the ones from 12 yrs ago with the post mounted pads. Kool stop pads will give all the wet weather braking you need. Disks make sense if you will ride a MTB through mud or a loaded tourer on long descents.

Just a gentle note that both disc and rim brakes have "calipers," so that might not be the best term to use to differentiate them.

You must be using long-pull style road levers, mountain V brake levers, or included hydraulic levers - so if you're running an average road bike, you'd be spending hundreds of dollars plus the cost of brakes to get all the bits associated with using them.

There are a few systems for sale for the last year at least that allow you to run disc brakes using standard short pull road levers. Avid BB7's are one and there's another Shimano version as well. Possibly more too. I've used the BB7's with Ultegra levers and really liked them once I had them set up correctly. A lot of attention needs to be paid to get the caliper adjusted perfectly parallel to the disc otherwise you won't get full power, lever travel will be high, and they'll squeal often.

I got them because I ride in hilly terrain and often in the rain. I only run a disc in front to keep weight down and to allow for easier rack mounting, plus a much wider selection of frames.