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Front brake sucks a**


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I posted this is the CRF250R forum with no replies, the bike is an 09 250R. When I got my bike the front brake worked excellent, and the pull was very firm the whole way, with no slack at all. As the pads wore down the brake started to not work as well, not very stiff, and quite a bit of slack. I just put new OEM pads on the front and it didn't seem to help at all. The brake pull completely in and bottoms out, and does so with not a ton of resistance. When I put the pads on I also bled the brake and made sure the oil level was full. The bike also has a Gold Fren aftermarket front brake line. Im thinking it has something to do with the piston or the caliper, or something.... any input is appreciated.

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you still have air in the master cyl. or caliper. re bleed until fixed . i've had problems with air getting in the master before and its a pain in the ass to get it out. some times it helps to put the master cyl. below the caliper and pump or vise versa helps get the air bubbles but your forsure still have air in the lines good luck

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you still have air in the master cyl. or caliper. re bleed until fixed . i've had problems with air getting in the master before and its a pain in the ass to get it out. some times it helps to put the master cyl. below the caliper and pump or vise versa helps get the air bubbles but your forsure still have air in the lines good luck

You really think so? I bled it a ton, and had to put quite a bit more brake fluid in it...

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The piston in the master cylinder is not large enough to carry a hose lenghts worth of fluid and air with one stroke of the brake lever. If you don't have a pressure or vacuum bleeder, it helps to remove the brake caliper and hold it above the master cylinder with the bleeder at 12 oclock. That way everytime you open the bleeder and the fluid and air moves towards the caliper, it will stay put until the next time you open the bleeder, and eventually work it's way to the caliper and out of the bleeder. That's because the air wants to go up hill.

Don't overlook the possibility that you have some mushy debris in your master cylinder reservoir, plugging up the feed hole into the piston bore. If this is the case, you'll never get fluid into the piston bore to even be able to bleed. I have also seen dirt build up behind the piston in the rubber boot area, and it will keep the piston from returning all the way to its resting point. This will in turn keep the piston in the way of the fill hole inside the master cylinder reservoir, and no fluid can get into the piston bore.

You can open and close the bleeder as you go through the bleeding process, but something that I do is remove the bleeder and use my finger as a check valve. When I squeeze the brake lever I have my finger off of the bleeder hole. When I let go of the brake lever I have my finger over the hole. When you let go of the brake lever with your finger over the bleeder hole, wait a few seconds before you remove you finger off of the bleeder hole to pump again. The fill hole inside the master cylinder that goes into the piston bore is small. So it may try to pull air bag in through the bleeder hole if you let go to quick.

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You really think so? I bled it a ton, and had to put quite a bit more brake fluid in it...

What can happen is the air will stay put some where in the length of hose as you bleed it. The fluid will carry it down very little with each stroke of the lever. By the time you try and pump again, the air has worked its way back up, but you're getting plenty of fluid.

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yes you can use a vaccuum bleeder but you can also manipulate the air by moving parts around. this is somewhat of a bench bleeding method. air is tricky its like water it goes places you'd never think possible. you've got air in there its up to you to get it out keep at it try short fast pumps not full pumps seems to work good for that. good luck 🙂

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