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Help bleeding front brakes

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I installed new brake pads and am having trouble building up pressure in front brakes. I keep filling it with fluid and cracking the bleeder and no air is comming out. I know their is fluid and i just cant get pressure on the brake lever. Any help?

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Another set of hands helps for the front brakes. Make sure you're fully engaging the lever, releasing whatever (might be almost none) pressure is in the line at the bleeder, tightening the bleeder fully before releasing the lever, then repeat. It shouldn't take much time as long as you aren't letting air back in the system.

I have to ask, why would you have to rebleed just from changing pads? :)

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When i opened the front reservoir..one a new bike i just bought...their was absolutly no fluid in the reservoir. Yea thats the method im doing. I just tried putting the caliper on the ground and seeing if the pistons were moving and I got them to move..but when i reattached the pads and caliper to the rotor it didnt move. Frustrating I must say.

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It can definitely be frustrating. Make sure that you're keeping fluid in the res. when working the bleeding procedure. Otherwise, you'll pump more air in. Good luck man:thumbsup:

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Front brakes take time...pump, pump, pump, then hold the lever and crack the bleeder. Repeat like 200 times. I find that even after a while you still wont get the right pressure.... so a trick I learned from a pro mechanic is to use a zip ty to hold the lever down to the grip, and leave it over night. The next day, bleed the crap out of the brakes again, and you should be golden. Another trick is to flick the brake line as hard as you can with your middle finger working from bottom to top.... this is usually done before you start bleeding though because it causes the air bubbles to go out the reservoir rather than out the caliper end (opp. of bleeding)..

Good luck!

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If there was no fluid you may have air bubbles stuck in the piston at the bars.

With the brakes and pads installed leave the bleeder shut and open the res. While continuously pulling the lever tap the res with a rubber mallet or 2x4. I stress "tap." Don't bang on the thing.

You need to get the bubbles to release from inside the piston. I had this problem when I rebuilt mine. I ended up buying a new piston that I didn't need.

You can also try tying the lever open (pulled to the bars) overnight. This should allow the bubbles to float up on their own. After all that just bleed as normal again just to be sure.

good luck.

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I had the same problem on my XR650R, what worked for me was to move the lever back and forth really fast to get the air bubbles to rise out of the piston, or I would fully compress the lever the let it snap back.

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You might try to reverse bleed it.

Get a spice injector and some fuel line then rig it up on your bleeder valve with no air in it. Open the valve and push fluid through the brake system. Also when bleeding it normally you might try to push the pistons all the way in by hand. I have gotten a bubble out by doing that in the past. I have gotten a stubborn bubble in a banjo bolt for the rear, but never had a problem with the front. You might look at that if nothing else works.

I've got a couple of spice injectors laying around. One filled with grease makes adding grease to bearings easy. No more getting it all over my fingers! Look for one with a plastic tip that you cut to determine the size if possible. Use the smallest hole that will work for what you are doing.

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Ok i semi-cheated and took the caliper off and let the pistons build up pressure then jammed it against rotor. I keep trying to bleed and pump the brakes but no pressure builds up against..but if i take it off from rotor the pistons move all the way in. Something broken here possibly?

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ok not sure what I should buy first to fix the problem. I can get clear fluid no bubbles or nothing all the way down to bleeder but cant get the usual hard spray out of the bleeder as I did with my rear brake. When I take the caliper off I can get the pistons to tighten up but once I put it back on the mount cant get them to tighten up. Ive gone through a gallon of dot 4 bleeding/reverse bleeding/vacuum bleeding.

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try a master cylinder rebuild kit and that should fix it.

also take the bleed screw out and check to see if it is messed up/ smashed

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my theory is..bleed screw is damaged from cracking it t0o much. Going to get another one and put teflon tape on it.

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