53

Hydraulics are used on higher end systems, cables are often a sign of a cheap brake set, so your observations are correct regarding "professional" bikes. However there are very good cable disc brakes (e.g. Avid BB7's) that are the exception that proves the rule. . Cables have the disadvantage of friction that hydraulics virtually eliminate. It is ...


36

One of the most advanced designs is the "floating rotor", made of two different materials connected together. They look like this: These are exceptional brake rotors. They are very rigid and won't bend sideways easily. Overheating is much less of a problem for these. If they are getting overheated, they don't bend that much because of the material expansion....


33

IS mounts (also frequently called IS tabs, disc tabs, etc) are unthreaded eyelets 51mm apart that bolts run through parallel with the hub axle. In almost all cases the brake caliper is then bolted to an adapter that has one set of threads for the IS mounts and another 74mm apart for the caliper. (There are a very few caliper models that omit the adapter, ...


23

Youll run into two types of metallic pads- sintered metallic and semi-metallic. The term "metallic" without any modifier gets used for a couple of reasons- a) many manufacturers don't offer both varieties of metallic pads for a given brake, so the type is implicit, and b) lots of folks don't know the difference or think the terms are interchangeable. They ...


22

In addition to @mattnz's response; most cable disk brake systems work by operating one pad only - and squeezing the rotor onto a stationary pad. This means that as the pad wears down, you typically have to wind in the moving pad (usually the outside one) to keep the right bite point. Hydraulic systems usually have opposing pads that self adjust for central ...


22

Usually, singles need to have horizontal dropouts so you can take the chain slack by adjusting the rear axle position. That means that any brake that is attached to the frame will "go out of position" when you adjust the rear axle position. That is, by the way, the reason why some horizontal dropouts are not quite horizontal, but diagonal: to be near-...


22

Well, there are lot's and lot's of commuter bikes with internal hubs and disk brakes. I see no reason why a single speed wouldn't work as well. A google search for "single speed cx bike disk brakes" turns up this beauty. http://allcitycycles.com/bikes/nature_boy_disc There are low budget models out there as well. Nashbar 29'r Single Speed Swobo makes ...


21

One thing that hasn't been mentioned, and probably trumps any mechanical advantages or disadvantages of disc brakes, is the fact that the UCI currently doesn't allow disc brakes in professional road races. This has a trickle down effect to you and me. Most, if not all, of the national racing federations follow the UCI's lead on equipment rulings. This ...


21

Ideally, the brakes should be able strong enough to break traction otherwise you will not be able to brake maximally (i.e., just before the threshold of losing traction). Rim brakes can do this, even in wet weather, if set up correctly. The real advantage of disc brakes in wet weather is other aspects of how the brakes perform. From personal experience, ...


19

Since bikes are usually shipped to the dealer with the wheels disassembled from the frame, the disc calipers often each have a plastic separator pressed into them that serve to prevent lock-up during shipping. The Hayes company even puts their brand logo on theirs. Since these are removed during assembly, you might be able to ask a repair person at your ...


19

Centerlock largely exists because since the beginning of modern disc brakes for bikes, Shimano has more or less alone had a weird cautionary take on the physics of rotor bolts theoretically being able to loosen in the six-bolt design. That's why their six-bolt rotors have always come with various retention systems for the bolts that nobody else bothers with. ...


18

You got the wrong pads. While it's possible to mix and match some pads, this is usually not the case. When replacing pads, keep track of: Pad material and what your rotor is compatible of. Some rotors have a "resin pads only" etched on. Consult user manual or manufacturer website for this info. Pad shape. Note the features, like "handles" shape, amount and ...


16

For the brakes to self clean and remain effective, the surface of the pad must transition from metal to void at least once every revolution across the entire pad (i.e. no continuous line of metal). The 'sawtooth' rim achieves this. Some very cheap disks do not achieve this. You may find the very good answer by @trailmax in this question useful.


16

Yes. Disc brake rotors can warp a little in use, or get bent from impacts and straightening them is routine maintenance. The basic procedure is to find spots where the rotor is bent inboard or outboard, and carefully incrementally bend it back. There are tools made for this purpose (e.g. Park tool DT-2) but the job can be done with a large adjustable wrench....


15

They squeal because water acts as a mild lubricant. That's why things are "slippery when wet" ;) The water makes it harder for the pads to grab onto the rotors. They'll grab for a small fraction of a second and then let go again, and they do this really fast. Imagine the squeaky sound that a your finger makes when your run it over a smooth wet surface, or ...


15

Disc brakes are generally more effective in the rain than rim brakes, but using rim brakes properly in the rain has served people well for many years. You need to feather the brakes to remove the water+crud from the rims. Softer brake pad compounds can also help you brake more easily. Also, having good quality brakes that are well adjusted is always a good ...


14

For use at home, there's no question that separate keys are more useful and more economical. A multi-tool has limitations that make it cumbersome to use in tight spots because all the keys are attached to the tool. Separate keys suffer no such limitation. Separate keys can be bought and replaced individually and very inexpensively -- not so with a multi-...


14

Simply put a bigger rotor provided better braking, and a four pot caliper provides better braking - better meaning more, and more control (Everything else being equal). For the same force between the disc and pads, a bigger rotor generates more torque on the wheel - i.e. more stopping force. It is running though the pads faster, generating more friction ...


14

Low-profile button-cap socket screws do have a design weakness. The button reduces the amount of material around the head and the recessed hex or Torx socket also does the same, exactly at the interface of the screw body and head. In this zoomed in portion of your larger photo, you can see just how little material connects the head to the rest of the screw: ...


14

If you are asking one of each type on the bike, yes. As disc brakes were becoming popular, many companies produces bikes with a disc in the front and a rim brake in the rear. If you are asking about one of each type on a single wheel (three or four brakes total for the bike) yes that would also be possible, but there wouldn't really be a point. Also ...


13

These things are called tightening plates or lock washers. Your suggestion was righ in where it goes, here's an exploded diagram and installed photo:


12

It isn't wise to install disc brakes on a frame and fork that weren't designed to withstand the unique forces that disc brakes generate, and you'll just damage your bike in the process. If your Haro does have disc brake mount tabs, then you can install them but likely only with smaller disc rotors. Remember that you'll have to get new wheels too, ...


12

Cable discs rule if you are riding a lot of third world. I am a million miles away from a shop, access to the oil, etc. A hydraulic failure would be disaster, whereas the worst thing that will happen with a cable disc is a lose bolt/need for readjustment. As smooth as hydraulics are, the fix of a failure when in the middle of nowhere (whether third world or ...


12

Advantages of 6-bolt: Not being patented by Shimano means more vendors offer compatible wheels/disks. Torx bolts require a smaller tool which is often included in many multi-tools so one can always have one on the road. Advantages of Centerlock: Faster installation and removal with a cassette tool; no need to fiddle with 6 separate bolts No need to have ...


12

On most cable disc brake systems there's a moving pad and a fixed pad. The moving pad presses against the rotor and bends it slightly towards the fixed pad. The rotor is made of rather springy steel, and is probably where the feeling you experience comes from. The barrel adjuster only addresses wear to the moving pad, but the fixed pad also wears in use. ...


11

I have been using disc brakes on my Mountain, Cyclocross, and Road bikes for well over 10 years now. Earlier disc brake versions certainly took a while to reach excellent, smooth, and modulated braking power levels that they currently enjoy. In that context, a poorly adjusted or designed disc brake vs. a well adjusted v-brake showed less performance ...


11

For a city commuter bike, don't bother with disk brakes - go for simple rim brakes. You'll want the reliability over all else. You don't need disks for most types of road cycling, as the limiting factor for grip is likely to be your tyre anyway. As regards shifters, go with whatever is comfortable for you. I like the combination of brakes and gear levers in ...


11

Rim brakes need an appropriate braking surface on the rim -- if you apply rim brakes to a rim which doesn't have an appropriate braking surface, it'll wear down the rims quickly to be unsafe to ride on (or possibly damage the rims in other ways). Disc brakes need a hub that can mount a disc rotor. As you can note from the two points above, they're ...


11

The hub for a disc brake wheel has the mounting for the brake rotor machined into the left side, and has shorter spokes that side to make room for the brake. If the eBay wheels are for rim brakes, they won’t have these disc mount features out the box. If the spoke counts match and are sufficient, you could theoretically rebuild the rims onto disc specific ...


11

The main reason is the 2020 Specialized Shiv provided by their sponsor is only produced in a disc version. You can see an article about the bike here: https://www.bikeradar.com/news/specialized-sworks-shiv-tt-disc/


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