any one try speed bleeders?

[redroadster]

Well since you asked.
You've braked by then ? Q
10,000-20k times ,or more many more right
With the pistons assy. Going 30 to 45 % down the MC cylinder ,the steel piston rubs scrapes the alloy cyl each time. Winter likely much harder on it , After 20k it has some rough gouges on the bottom of the cyl..
All of that going to the front of the cyl where the piston won't reach the rubber seals parts & debrie is pushed to the front too , most all gathering at bottom the bottom of the MC .which takes more heat from the engine and bakes these rubber particles to the cyl sticking them somewhat to it .if you bleed brakes in this condition many times it will grab the seal lip and fold it back or almost ,but also is the micro alloy fragments that stick into the rubber seal ,or your finger ( I've done it ,ouch) .
New dot 3 ,4 brake fluid is harder on. Rubber than old fluid chemically it eats / softens it
The Master Cyl will usually push thru all at once when it has been fine ,often on a lite brake apply loosing frt brakes .
Many old cyls have a slow leak, test by press normal medium hard slowly back off then hold light to very light pressure and you may feel the pedal sinking way more than it should and can go all the way down