no front brake

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Sep 17, 2000
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#1
After putting my front caliper back on I've now got no brake lever pressure. I've read previous threads here and figured maybe it was just a bubble. So I took the caliper off again, took the brake line, master cylinder and lever off, thoroughly drained the whole system, put it back together, refilled the master cylinder and tried bleeding again. But I still can't get any pressure on the lever and the brake fluid doesn't even want to flow down to the caliper now when I pump the lever. This is drivin me nuts! It's like there's a leak in the system, but if that were true, I'd see fluid leaking somewhere, right? I keep thinking I'm missing something simple. I've bled brakes on my car many times and never had anything like this happen. Please help!!
 
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Apr 18, 2001
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#2
DIRTMONKEY... i once had the same problem on my 1997 yz125. Took the front brake completely apart and couldnt get any pressure through it for the life of me. I dont know what made me think of it or how i came about the answer but what i had to do was replace all the copper washers on both ends of the brake cable. Just go to a local hardware store and pick up a couple copper or bronze washers of the same size and try that. It worked for me! Good luck and let me know what ya find out!
 
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#3
Instead of buying one of those expensive vacuum pump bleeding systems, i went to tractor supply and got a big 50 cc veterinary shrynge and some clear tubing that would fit over the end of the shrynge and bleeder nipple. I've found the best way to get all the air out of a front brake like this is to fill the shrynge and tube with brake fluid (no air bubbles) put it over the bleed screw, then crack it and force the fluid UP from the caliper to the master cylinder. It'll make alittle mess as all the fluid comes out of the master cylinder, but it will also take out the air from the caliper and line and master cylinder and almost guarentee pressure from the first squeeze of the brake lever.
 
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#4
Hog -- that's definitely an idea I haven't heard yet. Thanks.

I would've never thought bleeding the brakes would be such a pain in the a$$. Why is it so tough to get lever pressure back? After blowing away most of the day jerkin around with this I was almost convinced the brake line, the caliper or the master cylinder were toast. Even if there are air bubbles in the line, shouldn't I be getting some pressure?
 
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#5
DIRTMONKEY... i gotta say once again! TRY THE WASHERS!!! You sound exactly like i was. Spent the whole day and finally fixed it in 2 mins and 30 cents later.
 
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#6
One of the reasons bleeding the front brakes is such a pain in the a$$ is bacause the caliper is at the bottom of the forks and the master cylinder is WAY up top on the handlebars. Any air trapped in the system is trying to go UP!!! When you pump the brake lever, you are trying to build pressure in the system that has air in it. When you open the bleed screw, you are trying to force the air bubbles DOWN the line into the caliper and out the bleed screw. So, you pump and pump and pump.....as soon as you stop....the air starts RISING again and it NEVER gets down to the caliper. Just seems logical to use mother nature against herself and let the bubbles rise and force them out the master cylinder than to try to move them little by little with the teenie weenie amount of fluid the master cylinder pumps out each stroke.

Of course DesertGuy is right too, if those copper washers are bad, NO amount of bleeding is going to get you any pressure or get the air out.
 
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#7
Ok, finally. Syringe trick worked. I could only get a 5 cc syringe today so I had to inject about 8 vials to make sure the bubbles were out. The lever could still use some pressure, but at least its now pushing the pistons and I can use the brake. The washers are already new so that's why I wasn't putting that solution at the top of my list. Anyway, thanks a tonne for the help!
 

TimW

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Feb 21, 2001
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#8
Front brake bleed

I had the same problem with my kdx and some on the forum told me to hang it upside down overnight and then bleed it off the bike with the caliper elevated and it worked awesome. I had pumped and pumped thinking there couldn't possibly be any more air in it. It saved me from total frustration!
Tim
 
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#9
yea....that works too, but involves removing the caliper and finding something/someplace to hang the caliper higher than the master cylinder. i think the syringe method is faster.

to find those LARGE 50cc or bigger syringes, go to your local Tractor Supply store and look around the veterinary supplies. think they are a buck or two. you'll also find this useful for filling and draining other oils around your garage (like injecting a few CC's of oil in your forks that leaked out)

glad it worked for ya.