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The title might be wrong, I am not familiar with the terminology here.

I just got a BR-M445L front hydraulic brake. Installed it - this stuff is MUCH easier to install than a cable disc brake.

Now my problem is that in order to apply maximum braking force, the lever has to be pulled all the way to the handlebars.

I discovered the reach adjustment screw on the lever. With this screw, I moved the "at rest" position of the lever further from the handlebars. Thus, the situation is somewhat better now.

However, what I would want to do, is leave the lever not too far from the handlebar, and remove the "free travel" - the part of the lever's path, during which the pads do not contact the disc at all.

In other words, I would like to have 2-3 cm of travel of the lever, instead of 5-6.

There are a couple of screws on the calliper, but I am scared to touch them, before knowing what I am doing. One is on the entrance of the hose, similar to a cable brake adjustment screw. The other is at the base of a small opening, covered with a cap.

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2 Answers 2

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The brakes should adjust themselves automatically. Try pumping the lever all the way a couple of times. If that doesn't help, or the contact feels squishy, the brakes probably need bleeding. Either do that yourself or take the bike to your LBS.

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Thanks. I have seen that Elixir 9 or some such have "contact point adjustment". Is this the same as what I am describing in the question? If so, there is not way, except on very high-end brakes, to adjust the lever travel? –  Vorac Nov 22 '13 at 10:31
    
The "contact point adjustment" is a tweak for lever travel, and it's only available in high-end brakes, as you write, but no brake should have more than a few centimeters of travel if properly set up and bled, provided the pads and rotor are still good. My Elixir 5 have less than 2cm iirc from full release to maximum contact –  arne Nov 22 '13 at 10:41
    
thank you very much. Do you have, by any chance, a favourite tutorial on bleeding those boys? This is going to be my first time. –  Vorac Nov 22 '13 at 11:00
    
The Avid bleed kit has a very good manual, and I suspect the same for the Shimano one. However, be prepared to bleed multiple times until you are happy. I needed three attempts the first time ;) –  arne Nov 22 '13 at 11:31
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You need to bleed your brakes. The need for bleeding breaks arises when air is introduced into the breaking system, creating air bubbles. Shimano bleeding is easy, but an LBS might be the best bet unless you would like to invest in a bleed kit and some mineral oil.

Unscrew the bleed cover on the brake lever and screw on the reservoir. Attach the syringe (filled with mineral oil) at the caliper after removing all the air bubbles from the hosing and give the cap screw at the bleed point a quarter turn. Fill the brake system with mineral oil until the collection of mineral oil in the reservoir is no longer bubbling. Do not pull the break lever in the process.

Once that is done, do not pull the break lever until the wheel is mounted and rotor seated. Doing so will cause the pistons to move closer towards the rotor(helps when your pads are wearing down), leaving you unable to seat the rotor. The pistons can be pressed gently back into place with a tire lever. But this is also a way to introduce air back into the system.When you have finished the process of bleeding and re-seated your wheel and rotor, pull the levers until they are hitting firm and consistently.

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Beware! Not all brakes use mineral oil. IIRC, only Magura and some(!) Shimano models do nowadays. –  arne Nov 26 '13 at 13:09
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