A quick way to test the master and the line to the slave is disconnect the line at the slave and use a proper copper washer nut set and see if you can hold firm pressure with the lever. If you get a good solid response with the bottom of the hose plugged off then you know the master is still ok.
I have recently taken my slave apart only to find tons of sediment and garb that essentially cut a groove into the slave cylinder seal, so once I cleaned that up and replaced the seal I was goo to go.
Unlikely but you may have a bent rod from the slave going through to the clutch.
These are all some things to check before you have to open the clutch assembly.
If you need a copy of the '86 factory manual for that clutch, get me a mailing address and I'll send you a photo copy of mine. or you could go buy one at the local suzuki dealer. I like the Suzuki manual better than my Clymer manual.
Ok, first I've got a 1991 GSX-R 750 with a 1986 750 engine. My 91 blew and the 86 was all I could find to replace it. The engine has always been strong, until today.
I was ridding along on city streets and I pulled the clutch handle in to shift and about half way back, it just goes "pop." After that there is no responce from the clutch and the handle feels really loose. I could pull the handle all the way back and gas it and the bike would take off like it was still in gear...cause well, it was.
The clutch is a hydrolic clutch so no its not the cable. I've been told that I probably broke on of the bolts on my clutch basket.
Hopefully I can fix this myself. I've never worked on a Motorcycle engine before, but I am damn good at working on Honda Car Engines. I've got a full set of tools...but is there anything you guys can think of that I would need to know?
These guys all pretty much covered your question. Have you checked for fluid leaks at the master & slave cylinders?
If you do get into the clutch basket,they are really pretty simple. It is a good idea to have a good manual(from Suzuki) to refer to.