1ST gen, Slave or clutch?

Last month I rebuilt my clutch slave cylinder as after riding for about 45 mins
the clutch would start slipping. It seemed to work fine until this week when it started
slipping again. So into the shop it went for a new clutch ( 53000 K original clutch).
Got it back today (Barnet and Honda parts) and it was unbelievably great for about
45 mins and again clutch started to slip, getting worse and worse until no clutch at all.
I leaned down and put my hand on the slave cylinder and it was fairly hot, so I'm
wondering if I should recheck the slave. Any suggestions would be very welcome.
I'm going to pull the slave cylinder tomorrow and check it and take measurements
against the FSM and see what's up. It's an 84 VF750F.
Thanks

 

Clean out the clutch mc paying special attention to the small fluid return hole. Not likely any problem with the slave cyl.

 

Thanks Squirrelman I'll get to that tomorrow. I released some fluid from the
bleeder on the slave and it released the clutch so the master is next. By the way when
I put the bike down for the winter I'll be pulling the carbs to send you, should be end of November
when I get around to taking them off. I'll PM you when I'm ready to send them.
Thanks
Garry

 

Cleaned out the master and it was working ok, then about 45 mins into ride it did it again.
This time I think I'll take both master and slave and check and clean everything. When it
I just slightly released and retightened the bleeder screw and it work fine on the way home.

 

Be sure not too over-fill mc as there should be some air space above the fluid.

 

Follow Up:
Seems that I must not have cleaned everything as well
as I thought I did. I cleaned master, line, and slave.
Then hand bleed and went out for about an hour and
everything seemed fine. Thanks Squirrel