400ex rear caliper bleeding off?

[Tyl3r]

So I've been trying to get my rear brakes back in order on my quad and its been driving me nuts. First I bent the rotor my first day out at Powerline Mem day weekend. That pretty much caused the pads to completely wear out. So I put on a new rotor and pads. Still no brakes.

I was getting fluid from my bleeder, but there was no pressure coming out. So I figured the master cylinder wasn't holding pressure, so I got a rebuild kit for it. Put it all back together,bled the brakes (didn't bench bleed the master cylinder? do I need to? is there a way to?), had some pedal, was getting pressure at the bleeder, thought it was great. I drove it out of my garage... no phuckin pedal!

Here's where I am now. I can bleed it and get a little bit of pedal. When I hold the pedal down, it will fade off. I could see a little fluid coming out of the boot in the parking brake. So I took it off, and could see fluid is coming out from inside of there. My guess now is that there is a seal in the caliper that is blown out, allowing fluid to come out there and not holding pressure to push the piston out. Does this sound right? Or is there some sort of relief in the caliper for in case your piston is seized? Or did I miss something else along the way? I just figured I would ask before I go ordering more stuff that I may not need lol

[rbates9]

If it is leaking from the park brake screw you will need to fix that before going further. Is that one of the calipers that the park brake part is bolted to the back of the caliper and can be removed? Also with a bent rotor that ate up a set of pads the caliper probably got hot and melted something.

When you get the leak fixed then try bleeding the caliper with it held up in the air. Might help get the air to go out easier.

[diymirage]

I had a similar issue with my KDX front master cylinder and even after it was properly bled it still felt pretty mushy
I kept a zipty on the lever for a day or so and that did the trick

[Tyl3r]

Well, I didnt feel like joining yet another forum, so I asked on the dirtbike/jeep/four wheeling forums I'm already a part of. But then I broke down and did it lol

The 400ex guys are saying the factory parking brakes are notoriously problematic. Their suggestion was to remove all of the parking brake stuff from the bike and buy a parking brake block off plate for the caliper. I guess that's what I'll be doing then. I never use the parking brake anyways, I'm soo use to driving manual shift trucks without parking brakes, I don't even think to use it lol