Methinks there's a leak in the master cylinder somewhere leaking back into the reservoir.
Either that or I forgot to tighten the clutch line after I took it out to inspect it. No stoppages, no leaks found. A slightly corroded Zerk fitting but that shouldn't be the problem. I will likely replace it anyway because it's only $.50 at the hardware store.
Mostly I'm waiting until it's warm outside again in April or so before I get back at it.
My Seca 750 only needs new turn signals and an exhaust so I may do that first and go after the Sabre later. At least I know what's wrong with the Yamaha and can fix it easily, if not cheaply. Then I can sell it and get that Shadow 750 I've been wanting.
Brian