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Brakes refuse to bleed!

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Alright, so today I got done drilling out and retapping my CR80's master cylinder. Obviously I had to drain the brake fluid so no metal would get in, after I was done, I went to go and bleed the brakes, but no matter how many times I pump the brakes, hold the lever all the way down, and open the bleeder, once I close it up, it goes right back to no resistance (only from the spring). When I pump a little more, I get some resistance, but its very mushy.

Any help? I'm stumped, no, I will NOT, I repeat, I will NOT buy a brake bleeding kit. Don't even say it.

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attach a piece of clear tubing to the nipple, backfill the tubing first(you need a friend to hold tubing up so no fluid spills). take off top of MC and fill w/fluid, crack the nipple and let the fluid drain into a catch can( now lower the end of the tubing in the catch can). the tubing,being backfilled ,will pull a vacuum and assist in the bleeding. Just keep filling the mc until no bubbles come out the line. The clear tubing is the key here . You must use the tubing or it won't work.

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If it is front brakes try bleeding with the banjo bolt where the brake line attaches to the master. There may be air stuck there.

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MITY-VAC instead of the ARCHAIC WAY

reverse bleed with big syringe

MOST DEF. crack the banjo bolt at the lever once ya get the air outta the line/caliper..

tap/flick the end of your lever ever so slightly to knock the bubbles off the plunger inside the master

take a screwdriver handle and tap up and down your brake line to help break up any bubbles that may be in there

stand on one leg, hop up and down and pray to the GOD OF DOT 4 while holding your tongue just right......

good luck

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I'm stumped, no air is coming out of the line! The pads are not worn at all either!

I've trying gravity bleeding, reverse bleeding (syringe), pump bleeding, and still nothing! Can some get me a pic of the banjo bolt?

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banjo bolt holds the brake line to the master and to the caliper... pump up lever and crack the bolt (watch your eyes) do it a couple times and see if it helps.....

could be the resy's plunger is wore out/knicked/got a hole in it...

also make sure the small hole/s in the bottom of the resy are clear and not plugged up....

banjobolt.jpg

cloggedmaster.jpg

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Banjo bolt didn't help, BUT, the master cylinder of this bike has this little plastic screen thing covering the hole, and looking at the holes with a flash light showed a lot of dirt and stuff down in their, I'm gonna pull off the line and blow the master cylinder out with 60PSI of compressed air, I'll see what happens.

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Ban I'm gonna pull off the line and blow the master cylinder out with 60PSI of compressed air, I'll see what happens.

thinking thats NOT A GOOD IDEA.. there are rubber diaphrams in there that you could displace.. you need to pull it down and clean it correctly....

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Well, cleaning the sediment out didn't work either. I just wanna ride the god damned thing. Any other ideas?

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Take the banjo bolt out and hold your finger over the hole. Fill the resivour. pull the handle an let the air out of the hole. now push with your finger to seal it up and let the lever out. your finger is acting like a one way valve. heep doing this untill ou get solid flow with each stroke of the lever. then put the banjo bolt back in without letting the resivour drain. now bleed the normally.

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Would you like to buy it for me?

Ill try the finger of the banjo tomorrow.

Then ride with no brakes, why would I care? Sounds like the master is toast.

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get a replacment master cylinder kit, the seals in your master cylinder are broken and the fluid is not bein kept in place to hold pressure, happened my 250

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Then ride with no brakes, why would I care? Sounds like the master is toast.

serious. pretty obvious the mc seals are done or the cylinder itself is out of spec.

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Actually, pretty sure I found the problem.

2011-10-21_17-43-40_905.jpg

When I'm bleeding the brakes, the bleeder when closed allows air and fluid to go back into the system. I'm gonna order a new one and see if that fixes it. If not that, then looks like I'm gonna have to spend 200 bucks on a new master cylinder :thumbsup:

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