Brake Bleeding

May 18, 2012
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Scotland
hi guys i am wondering how you bleed front hydro brakes? also what is the bracket thing and where does the long thing get bolted on?

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The bracket attaches to the top clamp for your steering stem. Remove the two bolts, slide them through this bracket, and reinstall. It just serves as a cable/brake line retainer. The open (looped) side faces the right side of the Blaster when you are seated on it.

Now for the bleeding. There are a couple different techniques, and they all work fine. What I do is to start by installing all the brake components on the Blaster. Now take the cap off the master cylinder and get yourself some fresh DOT 4 brake fluid. Open one caliper bleeder valve (bolt) at a time, and pump the master cylinder lever until fresh fluid squirts from the open bleeder bolt. Now close the bleeder, and repeat for the other caliper. Be sure to keep brake fluid in the reservoir on the handlebars. If you let it run dry, you'll get air bubbles in the lines and you'll have to start the bleed process all over again.

Once you actually have brake fluid pumped to both calipers, you can begin the bleeding process. Top up your master cylinder reservoir. Dab a little grease on the threads of both caliper bleeder bolts to help keep air from entering around the threads. (You can clean it off later). Squeeze the lever on the master cylinder and hold it down. Now, pick a caliper (doesn't matter which one), and crack open the bleeder bolt for a couple seconds. Brake fluid and air bubbles will run out. Close the bleed bolt and release the master cylinder lever. Now repeat the process.

Squeeze, loosen, squirt, tighten, release. As you start getting the air out of the brake lines, you'll feel the master cylinder lever get hard, as it is supposed to do. You are through bleeding when the air bubbles stop coming and neat fluid is expelled from the bleeder bolt.

Once one side has been bled, switch calipers and bleed the other one. Then you're done!

The process can take 20-30 mins if you've never done it before, although it is pretty easy once practiced. Don't let the master cylinder run dry, work carefully, try not to make a mess (this whole process is easier to do with the front wheels off and a piece of 3mm hose slipped over the bleeder bolt head to keep fluid from running everywhere), and you'll be good to go! :)
 
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