Hydraulic Clutch - Do they Leak?

I have a 2008 Breva 1200. I took it for a run Saturday and noticed that the clutch was coming back to the bar and not disengaging properly.
I stopped at a mates house (which was where I was heading) and had a look - the reservoir was empty.
Topped it up, and got the air out and normal operation was resumed - enough for a good ride home again.

  1. Is a leaking clutch slave cylinder a common fault on theses bikes?
  2. Are there any other ways the fluid might disappear.
  3. How many miles can I expect out of a clutch? Is it worth taking the actual clutch apart whilst I have the swingarm off and replacing the friction plates?

The bike has done 47,000 miles.
The clutch looks identical to older tonti framed bikes with cable clutches so I expect the wear would be similar,

Hi des
I fitted new clutch ect at 50000mlsThere was lots of meat on them. I had a new oil seal fitted the one that fits behind the clutch so replaced the lot. But as I said miles more ware left. Bike has done 73000 now so just run in!

Regular Clutch hydraulic oil changes are recommended by some of the “guys that know”

Given the ease of doing it with the remote bleeder - you might as well!!