Repairman,

Sounds like air in the system but I am no brake expert, other than offering my experience when upgrading my M/C. I had to bleed multiple times using the pump the pedal method. I did this so many times I rotated around my family members to be the pedal pumper ("down....hold....ok up...wait oh crap"). Can't tell you how many bottles of fluid I pushed through.

I assume you are bleeding starting at the farthest wheel, etc. I haven't used a power bleeder, but I wonder if there is air getting in somewhere. Try the pump pedal method?

Finally, you might bench bleed the new M/C first using short brake lines and plastic clear tubing back into the reservoir to see if there are any bubbles. Once the air is out of the M/C, then install it and then bleed the rest of the system.

waggin

1985, 245 turbo wagon
1965, 220 wagon