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24

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 ...


19

What you experienced was brake fade. There are two reasons why it happens: The fluid inside the brake boils releasing gas into the system which makes the brakes feel spongy and then non-existant. The pad and rotor heat up sufficiently to not work, this feels like you are applying the brake but it doesn't work. You look to have experienced the first. ...


18

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 ...


18

First of all you need to tell the LBS (local bike shop) that the disk can be "fixed". Then you need to find another LBS because they are either amateurs or are simply trying to make you buy stuff that you don't need. You need to remove the oily disk from the bike and use a bike degreaser or alcohol on it to remove all oil. Rub with a clean dry cloth or ...


17

I think the answer he was looking for was how they adjust as the pads get worn. There is a check valve in the master cylinder, that will allow enough fluid from the reservoir when the lever is pulled. If more fluid is needed because of pad degradation, it passes it into the active system. Therefore with more fluid in the system, the piston is pushed out ...


15

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 ...


14

Look at any high end bike and you will find hydraulic disc brakes. There will be people who argue the pros/cons of hydraulic vs mechanical disc brakes but it's hard to deny what the entire industry is putting on their most expensive rigs. For ease of stoppage, minimal brake fade and ease of modulation - the hydraulic disc brake wins hands down. You can ...


12

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 ...


11

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 ...


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 ...


10

I have or have had bikes with mechanical rim brakes, mechanical disks (shimano deore), hydraulic discs (also shimano deore) and recently hydraulic rim brakes (Magura hs33). The experience I had says that: The force you have to apply depends on brake-system preload / elastic constant (lever spring + actuator spring), cable friction, and actual, braking, ...


10

The least you need to do is bleed the brakes to remove trapped air. It's best though if you completelly change the fluids and bleed. You can do that in an LBS, or yourself if you have a bleeding kit and know how to do it. The reason for the behavior you described is that air is trapped in the system and makes things mushy and unpredictable. The fact that ...


10

There are two risks to turning your hydraulic brakes upside-down. The brake system isn't filled to overflowing with hydraulic fluid: there's likely to be a small air bubble. Normally, this sits at the highest point of the system: the oil reservoir at the brake lever. There, it's not compressed by the piston when you brake, so it can't interfere with ...


9

It's not for hand signals. "Left hand only" signals were originally designed for cars. You couldn't use your right hand out the window, so you could only use your left. Using both hands to properly signal on your bike is far more clear. It's used on motorcycles due to the fact that the throttle is on the right hand, so you want to keep that engaged at all ...


8

Hydraulics are the same for car brakes, as for these style brakes, as anywhere else in the physical universe. Liquids have an amusing property that they do not compress well, if at all. (They do of course compress, but not very much in the grand scheme of things, and it takes a lot of pressure to noticeably compress them). Thus your hand started breaking ...


7

You need to bleed your hydros when they get a squishy feeling. They should be pretty close to the rotor, but if they are rubbing a lot, then you could try to recenter the pads around the rotor. To do this: Loosen the bolts attaching the brakes to the fork (or the adapter). Grab the corresponding brake lever and hold it in place. You can use a rubber ...


7

This document covers all your questions, and is from the manufacturer. http://www.hayesdiscbrake.com/wp-content/themes/hdb/pdf/45-14550DEnglishForWeb.pdf Looks like pad replacement/adjustment is easy enough, and you may need a kit for bleeding. Good Luck


7

There are 2 types of hydraulic brake systems, referred to as open systems and closed systems. Open systems have a reservoir, with a cap, usually on the brake lever, above the master cylinder. These systems, when proper care is taken, can have fluid added, or hoses trimmed without rebleeding the brakes. Closed system brakes, like most older Hayes brakes, ...


7

1- Disc brakes perform better in wet weather. If you choose rim brakes, aluminum rims offer a better braking surface than carbon rims. Hidraulic brakes adjust for pad wear and both pads move inwards to press against the disc surface. Mechanical brakes push one pad (usually the outer one) onto the disc, and the disc has to flex to touch the other pad. 2.- ...


7

That is normal behaviour. You pushed the piston way out, so oil from behind it found a way out. General actions suitable for your case as well: remove wheel remove pads carefully push the lever a couple of times in order for the pistons to extend a couple of mms. if one is stuck, make sure you push the other one with a plastic tyre lever while pulling the ...


6

The advice I have seen for a stuck piston is a) hot soapy water, followed by Isopropyl Alcohol, followed by a small amount of brake fluid (Use the same that is in you brakes - mineral in your case) to lubricate the piston. If you google for "Stuck Bicycle Disc Brake piston" there is quite a lot of useful advise Warm soapy water on it's own cannot hurt. ...


6

All brakes work by converting kinetic energy into heat through friction. In disk brakes, the heat builds up in both the rotors and calipers. Under heavy sustained braking, such as down a long steep hill, the calipers can get hot enough to start to boil the brake fluid. Because gases are easily compressible, boiling brake fluid causes a loss of braking ...


6

Short answer is don't throw out you brakes just yet and a different material MIGHT make the squealing stop. What you are experiencing is quite typical. Mine are really bad sometimes if they are wet or have dust on them. A few max effort stops fixes it. Steps to address, in a rough order based on cost and hassle factor, and no guarantee of success... Find ...


6

Most likely cause if the disc and pads are contaminated. What did you wash it with? Many cleaners leave a residue. Worst case the pads need replacing. The discs should be well cleaned before installing new pads - Use a solvent such as brake cleaner, methylated spirits or Isoprop alcohol, and rub the discs to be certain no contamination is left on them. ...


6

You don't need to remove existing fluid prior to bleeding. Unless you use two incompatible fluid types (for example replacing DOT 5.1 with 5), mixing an existing fluid with new one is completely normal and part of standard procedure. The only situation where you may want to remove the old fluid completely is if you know it has ben heavily polluted with ...


5

Answer to part one: Yes, within reason, it's true. Answer to part two: It works in a very simple fashion. Each time the lever is pulled, enough fluid to move the pistons, and therefore the brake pads, is pushed out of the caliper far enough to contact the brake rotor. As they move out of the piston, they push past the caliper seal. The flex in the ...


5

Many high end hydraulic systems on bikes are very much the same design as the car & motorcycle variety. However there are cheaper cable/hydraulic type brakes for cycles avalable. What happens in the fully hydraulic system is that the fluid within the system is put under pressure by you pulling on the lever, but the fluid and the system itself will not ...


5

Generally speaking you should just be able to take off your wheel and grab them with some needle nose pliers. I just grab onto the tab (see picture) and slowly ease them out. Mine are just held in with magnets. More info is probably needed for a better answer.


5

There are plenty of advantages to disc brakes while mountain biking. In my opinion, disc brakes give much better feedback to the lever with almost no fiddling with them. Rim brakes can be set up to work as well, but it has been a long process every time I've tried it. Rim breaks also can cause problems by heating up the rim itself, and as a result the air ...


5

From my experience racing USAC Collegiate xc and short track, disc brakes are the way to go, and I prefer hydraulic to mechanical, as long as they're the right model. You can find a lot of reviews on the mtbr.com forum about disc brakes to find one that would work for you. The Avid Elixir R SLs I use on my full-suspension mtb have never let me down and are ...



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