1996 RT rear brake no worky.

[Belquar]

It isn't my bike. It is my Dad's RT. My GS is in the shop and he has been letting me ride his bike. Well...it gets me around so I am grateful for that but....

The rear brake is not working. Gets a little grab initally then bottoms out. If I pump it I can get that initial grab but then nothing. I just hooked up the mighty vac and ran half a bottle of DOT 4 through the system. All fresh clean fluid. No air that I know of. Still can't build up pressure.

Thoughts?

Thanks in advance.

Brian

[lazywizard02]

Without knowing much about anything, I would examine:

Does the Master cylinder work? Is the connection made from the pedal to the cylinder?

Is the hose damaged or kinked?

Is there a pebble interfereng with pad travel? Are the pins straight?

Does the caliper have an obstruction in the oil passage?

Are the pads glazed? Is the disk greasy? Does the brakelight work? Does the brake lever move across its range?

[Belquar]

Without knowing much about anything, I would examine:

Does the Master cylinder work? Is the connection made from the pedal to the cylinder?

Is the hose damaged or kinked?

Is there a pebble interfereng with pad travel? Are the pins straight?

Does the caliper have an obstruction in the oil passage?

Are the pads glazed? Is the disk greasy? Does the brakelight work? Does the brake lever move across its range?

Everything appears to be in order. The pedal just won't build any resistance. Initial application yields a very little bit of braking and then the pedal just sinks to the bottom of its range without any further braking. I don't know much about the brake system so I am a bit at a loss without pictures to point at but I put all new brake fluid in. Bled the brakes with a mightyvac all to no avail. Don't know where to look next.

[RTNewbie]

Everything appears to be in order. The pedal just won't build any resistance. Initial application yields a very little bit of braking and then the pedal just sinks to the bottom of its range without any further braking. I don't know much about the brake system so I am a bit at a loss without pictures to point at but I put all new brake fluid in. Bled the brakes with a mightyvac all to no avail. Don't know where to look next.

You have a blown rear brake master cylinder. Very common failure.

Mine did the exact same thing so i took it apart and upon close inspecion i found a crack in the master cylinder cup seal. I tried to find the cup seal only but wound up getting a rebuilt kit and spare cylinder on ebay for cheap.

Don't worry, its a very easy fix.:thumb