Hello, I need some help in regards to motorcycle brakes. I have never had trouble maintaining or servicing the brakes on my own bike, but when working on my friend‘s bike I had an issue. He let his rear brakes wear down completely metal on metal for a long time and just relied on the front brake. I know you‘re suppose to replace the rotor if it gets to that point but we did not because he did not want to spend the money. I replaced the brake shoes and bled the brakes and replaced the fluids but the back breaks won‘t work at all. Is this because of the damaged rotor? Will motorcycle brakes not work at all if the rotor is worn down bad? Thanks for the help.
you already asked this and as everyone told you before you should be fine. You would know by now if it was a problem.
Brakes need 3 pieces at the wheel. Caliper, pads, and rotor. If the rotor has gone metal to metal long enough it definitely needs replacement. If you did not need more than one brake the manufacturers would save money and not give you one. And laws would not require a second. Brakes are important if they do not work you WILL have a wreck and you may kill or injure someone else, or yourself. Do brakes the right way, the one you hit may be me.
If he let go to metal, more than likely the o-ring (it's actually square) inside the piston the resides in the caliper got hot and is frozen in place. You will have to take it all the way off and put pressure air to where the banjo bolt would go and see if you can free it up. Now your caliper probably won't look like that. That's a front left off of an fxr that froze so solid 150psi couldn't break it loose. Makes a great paper weight. If it free's up it will make a loud pop. That's normal. Inspect the piston and bore. No damage buy a rebuild kit and try again.
