Shortening and Bleeding Shimano Disc Brakes

Here is a generic guide on shortening and bleeding Shimano Disc brakes.

OK, this is what tools you'll need if you have to shorten the hoses.

1. Decent cable cutters
2. an 8mm box spanner
3. a 3mm allen key
4. A socket wrench with a small socket on it (can't remember which size, but its probably an 8mm)

For the actual bleeding, you need the following:

1. https://www.tweekscycles.com/components/disc-brake-spares/shimano-br-m575-disc-brake-bleeding-kit
2. https://www.tweekscycles.com/components/disc-brake-spares/shimano-disc-brake-mineral-oil-bleed-kit
3. A syringe to use with the bleed kit

Here is what I do (this is mostly tailored for new Deore M615's, but can be adapted to the others).

1. At the lever, pull down the plastic cover over the hose where it joins the lever.
2. straighten the split pin on the caliper
3. pull out the split pin (or unscrew with allen key if its got one of those instead) and slide out the pads and the funny metal spider that holds them together.
4. put the yellow block in and secure it with a rubber band or a food bag metal tie.
4. using the 3mm allen key, undo the round cap on the lever. Make sure you son't lose the little plastic washer as otherwise you won't have a seal. Stick them to one side (not too close to the pads as you might foul them)
5. Screw the yellow reservoir (bleed tool 1) into the hole you've just exposed. Take off the lid and remove the needle in the middle.
6. At the caliper end, take off the little plastic cap over the bleed screw (I just pull it straight off).
7. Use a socket tool at the right size (can't remember which it is, but I'll check later on) and crack it open so it is just finger tight and not leaking.
8. Cut the hose that comes with the bleed kit in half (ish) and connect it to the syringe. Pull the plunger fully out.
9. Attach the hose and syringe to the bleed screw and open it. Press very slowly till all the oil is in the reservoir. Don't go too fast as it'll spurt out the top 10. Once its all out, finger tighten the bleed screw again and take off the syringe.
11. Put the needle in the reservoir.
12. Carefully unscrew the bolt underneath the lever cover that joins the hose to the lever using the 8mm spanner.
13. When its finger loose, unscrew it by hand.
14. When its fully out, you should be able to pull out the hose very easy.
15. Next, work out how long you need the hose to be. Take into account when you turn the handlebars.
16. Cut the hose as straight as possible using a decent pair of cable cutters.
17. slide the Olive you cut off the end back onto the hose and hammer in the connector insert (page 20).
18. If all goes well, you should now be able to reconnect the hose, screw it tight (not too tight, as those connector screws are pretty crappy and break easily).
19. Empty out the air from the syringe and fill it from the reservoir and the bottle of oil. Plunge it in and out a couple of times in the bottle to get as much of the air out as possible.
20. Attach the hose and syringe to the bleed screw again and open the screw.
21. Take out the needle from the reservoir on the lever.
22. Slowly push the plunger on the syringe in till the reservoir is filling up.
23. Slowly pull the plunger out and repeat a couple times, making sure you leave a little oil in the reservoir. This will make sure that the air is all out of the brake hose.
24. Once you've got as much out as you can, take off the syringe and tighten the bleed screw properly.
25. put the pin in the reservoir and unscrew it. empty it in the oil bottle.
26. Screw back on the bleed hole cover (making sure the washer goes on).
27. Slide the hose connector screw cover back up to cover the screw.
28. Take out the Yellow block and put the pads back in. They'll only go in one way but the little metal spider can be a pain!
29. slide back in the split pin and bend it back open.
30. Voila! Give it a ride.

With the calipers, what I normally do to get them centred is attach the bolts to the adaptor fairly loosely and with the wheel in. Then, I pull hard on the brakes and either keep the brake lever held with your hand, or bind it with some tight rubber bands. Next, with the pads fully fight on the rotor, tighten up the caliper bolts. You should find that there is almost not rubbing that way. If you still get a little rubbing, loosen the bolts a tiny bit and then push them with your thumb while spinning the wheel till you can get it to run freely. When you've got it, tighten up the bolts.