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Steve2011 01-20-2015 11:37 AM


Originally Posted by mywifesquad (Post 3275226)
There has to be something plugging your master cylinder. Compressed air may free things up.. But you would have to take it apart and re bleed the system..

Bearings should be separate from the hub and be replaceable..

Yeah I took it apart. The only thing I could remove was the handle from the cylinder. Not sure how to get the piston out. It's all one piece now. The other issue I have is I need new seals that go on the bolts that mount the brake liNE to the caliper and master cylinder. Any idea where I can get those? Been a couple motorsports places and they have nothing.

MPDano 01-20-2015 02:31 PM

Also, on these small chinese master cylinders, they are almost impossible to bleed through pumping the pedal. I pressure bleed mine using a large syringe hooked up to the caliper bleed valve. Open the reservoir and push the fluid using the syringe. You should see old fluid/bubbles come into the reservoir. Once clean fluid and no bubbles in the reservoir, the lines are bled.

If the pedal still goes to the floor, the master cylinder is bad. Non-rebuildable as far as I know. The only good thing about chinese master cylinders is that they are cheap to buy.

Steve2011 01-20-2015 06:37 PM

2 Attachment(s)
This isn't a brake pedal. Its a lever up on the handlebar that the master cylinder is all attached to. Ive attached a picture of the lever and master cylinder. There's another photo below as well. I am in need of the black handle on the shifter selector. Anyone know where I can get one of those or something like it. Grabbing threads with your hand gets old real quick.


Attachment 13742


Attachment 13743

MPDano 01-20-2015 07:32 PM


Originally Posted by Steve2011 (Post 3275275)
This isn't a brake pedal. Its a lever up on the handlebar that the master cylinder is all attached to. Ive attached a picture of the lever and master cylinder. There's another photo below as well. I am in need of the black handle on the shifter selector. Anyone know where I can get one of those or something like it. Grabbing threads with your hand gets old real quick.


http://i176.photobucket.com/albums/w...ps5d9048cd.jpg


http://i176.photobucket.com/albums/w...pscc29d157.jpg

Same idea. Bleed though the caliper. If no fluid comes up to the brake handle res, it's blocked somewhere. You can remove the hose from the handle to verify where the blockage is.

Steve2011 01-20-2015 08:09 PM


Originally Posted by MPDano (Post 3275279)
Same idea. Bleed though the caliper. If no fluid comes up to the brake handle res, it's blocked somewhere. You can remove the hose from the handle to verify where the blockage is.

The line is off and it flows fluid through it with no issues.

MPDano 01-20-2015 10:19 PM


Originally Posted by Steve2011 (Post 3275284)
The line is off and it flows fluid through it with no issues.

Ok? Did you reconnect and let it fill the reservoir? Once it's clear of air bubbles, you close the bleed valve while the syringe/hose connected. Then try out your brakes. Report back.

Steve2011 01-21-2015 07:51 AM

I don't have a syringe. I've been using a oil can that had a lid along with a squirter. I've got a piece of hose that goes from there to the bleeder. I've pumped forever and nothing ever gets into the master cylinder. If I disconnect the brake line from the master cylinder and pour fluid in the master cylinder. You can pump the handle all day and no fluid if any very very very little comes out where the brake line hooks up. When I say very little I mean a drop or two. Does anyone know where I can get the black knob that goes on the shifter selector at. I attache'd a photo a couple of posts before this.

Steve2011 01-21-2015 10:41 PM

Ok so I stopped and picked up a huge syringe today from a vet clinic. I also took the caliper completely off and cleaned it out. And I took the master cylinder completely apart. Reassemble everything and I tried to push fluid back up from the caliper to the master cylinder up on the handle bar and no fluid got into the resivoir. So we tried to gravity feed and put fluid in the master cylinder and we opened up the bleeder and no fluid will leave the master cylinder. We tried pulling it down through with the syringe also and we got nothing. WTH else do I need to do. I've bled brakes 1000 times on cars and have never had a problem like this. How do tell if the master cylinder is bad or if the caliper is bad etc...

mywifesquad 01-22-2015 06:46 AM

Since no fluid is going thru the master cylinder, Id say its bad.. Have you tried blowing compressed air in/thru the master cylinder? Its definitely plugged.

Steve2011 01-22-2015 08:40 AM


Originally Posted by mywifesquad (Post 3275412)
Since no fluid is going thru the master cylinder, Id say its bad.. Have you tried blowing compressed air in/thru the master cylinder? Its definitely plugged.

Yes it feels like air comes out. But like said I can disconnect the brake line from the master and no fluid will come out of master. If I pour fluid in the resivoir and have the line disconnected, fluid should come out of the resivoir where the line hooks up should it not???


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