1994 K75RT Rear ABS Brakes have no back pressure
So I drove about 10 miles into town and had rear brakes, pulled up to a stop light and the pedal bottomed out. There is no back pressure other than springs. Pumped several times with no change
Steps I've taken so far:
1) Checked reservoir, empty. Filled, no change in pedal pressure.
2) Vacuum bled brakes from rear caliper, lots of Bubblles. No change.
3) Vacuum bled brakes from ABS hydraulic unit, no bubbles. No change.
4) Installed new master cylinder and rebled system as above. Same results.
Steps I will take today:
1) Get a better seal at rear caliper bleed point as bubbles continued after I closed fitting. (Checked fitting, it is sealing)
2) Start disconnecting brake lines starting at the master cylinder, seal the ends and determine if I can pump up the master cylinder.
3) Pull caliper for inspection.
When I have bled, I have pulled through several reservoirs full of fluid
I noticed last night as I was hand spinning the rear wheel, there is the slightest resistance when I push down the brake pedal but I can't feel any back pressure in the peadal other than springs.
I don't see any fluid leaks or residual fluid on bike although I haven't inspected the caliper very close.
Any ideas would be greatly appreciated.