Introduction: How to Bleed the Brakes for Motorcycles

About: Design, CNC, powder coating and so much more.

In this instructable I'll try to guide you trough the procedure of bleeding the brakes.

Step 1: Watch the Video

Step 2: Here Are the Steps...

This is how I bleed the brake system.

It’s not a difficult process, but if it’s not done properly it can take all day and it can compromise the quality of the braking.

First of all I need to loosen the purging fitting on the brake caliper and connect it to a length of clear plastic hose. The hose needs to be routed upward and then looped around a couple of times so that the oil that will come out from the caliper will form a sort of a one way valve that won’t allow the air to flow back into the system. Then everything is secured with a zip tie.

Now I can open the reservoir tank…

And fill it up with DOT 5 brake oil trying not to make a mess like I’m doing right now.

To bleed the system and flush out the air I start pumping the lever and when the system is full, oil starts pouring out of the bleeding valve on the caliper. As you can see a mixture of oil and air bubbles are coming out of the valve. Those air bubbles have to go, because being air a compressible gas, it would compromise the quality of the braking.

After quite a lot of pumping and a few oil refills of the reservoir, we can see that the air bubbles are diminishing until they disappear.

At this point I can tighten the bleeding valve and then remove the plastic hose.

The reservoir can also be closed at this time and the braking system is ready to go... well, actually is ready to stop… anyway…

It’s time to remove the center stand and glance at the result of our hard work!

I’m very happy with what we did; the different elements of design are well implemented with the functionality of this project. The parts we made from scratch come out really nice and blend in with the existing pieces like if they were conceived at the same time.

The powder coating come out very nice and, although I do like the rough metal look, the paint makes everything look more professional.

Now all is left to do is try the bike out and see if everything works.