Bleeding Magura brakes

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[edit] Bleeding Magura rim brakes

There are two major ways of bleeding maguras - either with a bleed kit, or submersed in water - such as a bath or bucket.

[edit] Bleeding Maguras with a bleed kit.

[edit] Tools needed

For this method you will require a bleed kit. These can be purchased from many online stores or local bike shops.

A Magura bleed kit

[edit] Method

Loosen the TPA all of the way off.

Move the whole lever up so that it's pointing forwards instead of down. The bleed screw on the lever has to be at the highest point, so the air can escape.

Take the bleed bolt off of the slave cylinder. This one circled red; Click for image

Using one of the clear tubes, attach it to the syringe. Attach a barb to the other end of the tube.

Fill the syringe with water, or oil. People tend to prefer water because it gives a better feel to the lever rather than oil which can sometimes feel spongy. It's also free! I find it easiest to fill it with the tube and barb attached already, makes sure you get the most liquid in there.

Screw it into the bleed hole, making sure that the tube is full up with water before you screw it on.

Make sure you always bleed from slaves to lever

Undo the little grub screw on the lever body.

Optional Step Take the other clear tube and attach a barb to it. Screw it into the bleed hole on the lever.

Optional Step Ask someone if they can hold an old butter tub or something under the tube coming from the lever, otherwise you'll get oil all over your rim/rotor. This isn't too important if you're using water, but it's still useful.

Making sure everything is done up tight, slowly pump the syringe until most of the fluid from it is gone.

Now look at the tube coming out of the lever, if it has bubbles in you need to do that again. Note: I prefer to do mine without a tube.

If you're going from an oil bleed to a water bleed, you're going to want to flush the system, so take the syringe off the tube, and fill it with water again, then repeat the bleed process.

Once there are no bubbles in the tube coming from the lever, the bleed is done.

Take the pipe off of the lever and put the grub screw back in. Do this up tight. Remember: When you're taking the pipe off of the lever, make sure to leave the syringe on the pipe coming from the slave.

Take the pipe and syringe off the slaves, and replace the bleed bolt.

You should now have a working brake! If you have any problems, make sure you follow the steps carefully, you may have missed something out.

[edit] Bleeding Maguras in a bucket or a bath

Fill the bucket or the bath full of water.

Take the brake off of your bike and put it in the bucket/bath.

Undo both bleed bolts, the one on the lever and the one on the slave. (Underwater)

The method is tricky at first, but once you have the rhythm, it will take a minute at maximum.

Underwater: hold your finger over the hole on the slave cylinder (remember, when you have your finger on the hole, make sure it is tight and sealed against the hole, other wise it will take longer to bleed and may effect performance), press the lever all the way down, then hold your finger over the hole on the lever body, take your finger off the hole on the slave cylinder and release the lever fully, repeat until you no longer see any air coming out.

Do up both of the bleed bolts. (Again, underwater)

Take the brake out and it should be air free.

Revolver's Water Bleed guide can be found here - [1]

[edit] Alternative Syringe Method

Set the lever pointing vertically down first.
Fill the syringe and tube with fluid, get as much air out as possible.
Hang a pot from the bar/lever blade with a tube going into it from the lever bleed bolt, stick some fluid in there so the end of the tube is submerged.
Push the fluid through, then pull it back, then push it through, then pull it back. Pump the lever, flick everything, push it through and pull it back several times until no bubbles come out of the tube connected to the lever.
Disconnect the syringe. At this point fluid will start to drain down slowly from the lever end, don't worry it's just sucking it in from the pot, this helps as you can screw the bleed bolt back in as the brake is pushing fluid out so you can't get air trapped under it.
Take the pot away from the drain tube on the lever, it won't run out because it's secured at the other end. Keep it tipped up a bit anyway.
Tip the lever up vertically then put your thumb over the end of the hose, and unscrew the hose, your thumb sealing the end will stop the fluid running out.
Make sure the recess for the lever bleed bolt is filled with fluid and is vertical, then screw the bleed bolt in.
Then set the lever in to where you want it and wind the TPA in a little bit and set the lever flat or pointing up a bit, then crack the bleed bolt with a rag under it, it should push a little bit of fluid and air out, let it drain for a while with the bleed bolt undone about half a turn, then once it stops flowing the slaves will have hit their stops, so tighten the bolt back up.