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Discussion Starter #1
Well I'm at another road block. I fixed both my front brakes. New pistons and rubber fittings. I cleaned the breaks completes and made sure there was some brake fluid around the piston and on the rubber bushings before installing. All 4 installed fine. Connected them and added brake fluid and started to bleed them. The issue I'm having is the level is still way too easy to pump. The brakes were working before (barely) but they were. I would think it would work better now but for some reason I can't get it to build any pressure. What am I doing wrong? Using dot4 brake fluid and bleeding them with a bleed system. I believe I have all the bubbles out (2 hours later)...
 

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I have messed with lots of brake systems and it sounds like you still have air in your lines somewhere. It can be a real nightmare to figure out where. Good luck! I know the mighty-vac system has helped me in the past.
 

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I had a similar problem as well when I did my brakes. I used a bleeder for about an hour and still had a mushy lever. I think what ended up happening to me is some air got into the master cylinder valving when I ran the resi dry, oops. What I did that fixed my problem was give the lever a number of panic type yanks, full resi and cap securely on, and then went back to using the bleeder with resi cap off. I did this a couple of times with panic grabs on the lever and then back to the bleeder. It took a little bit but my brakes are now nice and firm and quick to respond.

A vacuum bleeder is key to getting the brakes bled. Hope you can get them sorted out!

Tony
 

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Discussion Starter #4
Thanks guys, I also feel there is still air in the lines. But the last thing I wanna do is buy something else to fix the issue.. Any suggestions on a cheap vac to use for this?
 

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In the manual it shows how to bleed brakes, just take resistor cap off, squeeze lever and loosen the bleeder on 1 of the calipers and once the fluid has come out of bleeder and lever is touching handlebars tighten the bleeder and keep doing it about 10 times per line, pretty easy.
 

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Discussion Starter #6
In the manual it shows how to bleed brakes, just take resistor cap off, squeeze lever and loosen the bleeder on 1 of the calipers and once the fluid has come out of bleeder and lever is touching handlebars tighten the bleeder and keep doing it about 10 times per line, pretty easy.
LOL.. Sounds too easy. Smoked an entire cigar trying to get the damn things as needed lol. Theres air in it, I know it... going to buy a pump today I think.
 

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Discussion Starter #7
I bought a hand pump bleeder on Amazon.. hope it works.. the way I have been doing it worked for the rear but not from. I will update everyone
 

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Jerry,

You can pick up one of those hand help vacuum pumps at any auto parts store or even walmart for that matter. They are pretty cheap as well, just in case you don't want to wait for Amazon lol. A vacuum pump is almost the only way to bleed these brakes it seems. Hope you get them sorted out!

Tony
 

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Discussion Starter #9
I messed with them, again. I just can't say there is any bubbles in the, I manually bled them again. Although, I see my brake pistons moving slightly. I feel like they are stuck in and not out.. the pistons are new on both side and same with the rubber fittings inside. Properly lubed up before input the pistons in... see photo.
 

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Discussion Starter #10
Bled the brake so with the bleeder hand vac I bought. Works well burn unfortunateky still in the same boat. The pistons are depressed in some, although they work when I pump the break they don't come out far enough. Today I'm going to remove the brakes, pads and with a c clamp I'll try to push in those pistons and then will retry bleeding the system again. Not sure what the issue could be now.
 

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Discussion Starter #11
So I broke down and ended up taking the master cylinder apart and rebuilt it with a kit. No change. So then I took both front brakes apart again, blew out the pistons with my air compressor, took the pistons out and places more brake fluid around the piston so it would slide in the chamber easier. Mounted them and applied pressure. Lots of air still in the brake lines so after about an hour of bleeding I was able to get the left side to work. Then started on the right side bleeding but that side seems to be much tougher. Brakes are still spungy feeling, not tight yet. But I'm pretty sure there is still some air pockets in the lines. I'm wondering now if my lines are the issue maybe? Anyways. They work, not exactly how it should work but they do.
 

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Discussion Starter #12
The verdict.


The Pistons were not moving well enough and were stuck in the "in" position. While on the quad, I used compressed air and pushed out the pistons, after that they seem to move much easier now so after installing the new and thicker brake pads, bleeding the brakes as needed, not the pistons are reaching the brake pads and the handle tightened up. I think giving the pistons that extra push gave it the movement it needed. Not sure why this happened but its done with and working so I am happy. Thanks for the help guys!
 

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The stock brake lines can be a bit squishy, especially as they age. When I made the switch to braided lines I was amazed how the difference in brake feel once I got all the air bled out of the system.

Little idea on the strength of the brake lines..........I actually ruptured my rear brake line when I stomped on it once during a ride. It wasn't a complete blow-out but enough to put a split in the brake line, this caused the rear brakes to fail as you could imagine. Now, some of this could be do to age, or poor maintenance by the previous owner, the brake fluid WAS almost black when I pulled the resi cap.

This may seem like a dumb question but I have to ask it just in case............your bleeders are on top of each caliper and not on the bottom correct? Your bleeder should be on the top of the caliper when installed correctly. Just a random thought that came to me and wanted to ask. This would make bleeding the brakes a royal pain and getting all the air out virtually impossible.

Tony
 
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