I think I need a new master cylinder. I can only get mine to pump fluid if my thumb is over the outlet hole.

So the question, is there a master cylinder from another machine that would be an upgrade over my warrior's stock one? I was thinking maybe one from a yfz or 450r would give more stopping power. It seems like the stock one on the warrior is a little on the weak side to begin with.

 

yea it does.. really anything should bolt straight up

 

yea it should bolt up but the problem might be the size of the brake line and make sure that the bolt will fit into the new mastercylinder I would say go with either another warrior,wolverine, or a raptor or yfz I would stick with a yamaha master cylinder unless you can find another that would fit

 

also I forgot to ask how are the copper washers and are there any leaks that you can see in the line by where you hold your hand

 

Are you leaving your thumb over the outlet hole on the return stroke? If you dont, youll never get rid of the air.
Almost all the jap master cylinders have the same size thread on the banjo bolt (M10x1.25), but the inner center hole is different on each model. As long as you use the bajo bolt from your machine, most any master will work. Some have brake light switches and some dont, mounted on the master. This may effect your decision on which master to buy.
I wouldnt give up on your master yet....if it produces pressure, its probably still good, and just needs to be bled of air.

 

What is your suggestion, if you think mine is still good? I tried everything I know and nothing helps. I know the lines are sealed right, and I know how to bleed lines, but nothing comes out. All I get is a gurgling sound on the caliper end from air moving, the fluid never leaves the reservoir.

 

How did the situation start? You changed brake pads? or did the brakes just go soft?

If you leave both bleeders open, and all lines tight,and lid on the master resi is off, gravity should take over and fluid should leak out the bleeders. Does it? If it doesnt..open the line at the master and see if the fluid flows out the bleeders . If fluid still doesnt come out, its blocked somewhere.
If you have a vacumn bleeder, you could try that.

Does the lever get firm before hitting the grip?
If so, Id Start at the master, and get the lever firm, then barely crack open the line at master. Let the air and fluid escape, and snug the line back up. A couple of these should allow you to move down to the caliper.
Bleeding can be frustrating..but like i say, if the master will build pressure at the outlet hole..its good.
If you can get fluid to flow from the master, but the calipers dont move, id look for a blockage in the line or caliper.
If you need to get another master, i see them all the time for 10 bucks or so on ebay.

 

I'm replacing the stock lines with a 2-line braided set. I don't think there's a blockage anywhere, because it doesn't build up any pressure at all, with the only exception being when I have the lines off the master, and cover up the hole with my thumb, then for some reason it works until I take my thumb back off.

I thought the fluid would run down the line by itself with the bleeders open, but it just sits there and nothing changes at all.

 

So if you disconnect the line at the master...and open the bleeders...nothing come out the bleeders? Im assuming there is at least some fluid in the lines, and calipers...but something should come out.
Id start by making sure the lines arent blocked...maybe use some compressed air, and when you get fluid to flow down the lines by gravity, then id start the bleeding procedure.

 

The lines aren't blocked, compressed air blows straight through them. Only a little bit of fluid dribbled out through them, not enough to actually come out of the bleeders, but when I loosened the line on the caliper, some ran out. Not much, but some.