Master Cylinder on my ATV took a crap ... What happened was the brake so tight for some reason, so I figured I'd flush and bleed the brakes. It appears the fluid was really bad, so bad there must have been water in there that nuked the o-ring in the master. Once I flush it, it would not build pressure and I saw some black crap coming up through the reservoir, which I believe is the o-ring. Anyways, I ordered a rebuild kit, $20, so hopefully that will do it. Since the ATV is up @ the property, I ordered a used master cylinder I found off ebay for $10 so I could just rebuild that one at home, then do the swap when I go back up. I'll flush and bleed again, and hopefully see some pressure. I never rebuild one nor changed one on a ATV, hopefully its not to crazy!