I did get a similar result on my motorcycle without a master cylinder being bad, but there was more to it than that. Last month I took it to a shop to replace the rear tire. They did that, but the tech who put the bike back together managed to leave out the inside rear brake pad. Despite the missing pad, it still worked so amazingly well that I didn't notice until the steel rotor had worn through enough of the aluminum caliper that the caliper pistons ran out of travel. The service manager seemed a bit embarrassed when I brought the bike back.

@westchester aut: This site sells parts. Go to the top of this page and click where it says "Buy Parts".

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.