I replace the pads on my rear brake a while back and haven't paid any attention to it since. It probably only has like 10 hours of ride time on the pads. I'm in the process of a full rebuild so i haven't been ridin and when i moved the blaster the yesterday i noticed the rotor looked worn. upon closer inspection the outside pad was completely gone. I have done tons of brake jobs on cars so i understand how this stuff works but thought i would ask what you guys thought would cause this. time to rebuild the caliper? don't remember the brand of pads but they weren't the cheapest ones.