clutch slowly stopped working

[Freddy]

On your bike it's hidden just behind the foam insulation where the line from the m/cyl attaches.  On the earlier bikes it's exposed.

I recently had the same problem as the OP but it wasn't air in the system.  It was a loose nut - the one that holds the star springs and clutch basket together.    I'd had it off 4 years, 20,000km ago and hadn't fitted a new one like the good book says.     I found the cause after fitting a repair kit to the master & slave cyls and copious amounts of fluid for bleeding.     Lesson learned. 

[GLA55Y]

Thanks for your reply Freddy, I was beginning to think nobody was reading the forum or had no knowledge of it!

[Boomer]

I replaced my clutch slave with one from Oberon Engineering. Since then no problems but you do need to refresh the DOT4 every 2 years or so.