Miles wrote:I have just read about your dilemma.
Having had some experience with slipping clutches.
I find it hard to believe your problem to be with the clutch hydraulics. If there was an issue with the hydraulic system you would have problems trying to engage gear.
The fact you say your clutch only starts to slip when up to operating temperature.  Would leave me to believe you have some form of oil leak on to the clutch plate possible crankshaft seal or gear box seal.
This seems to be my problem! 

  The clutch is not disengaging properly. It'll find gears easily enough when cold, but the moment she warms up 1st, 2nd and reverse are a nightmare to find. 

  I've tried force bleeding the system, but to no avail. It feels almost like an automatic when I'm waiting at the lights with the clutch depressed, in that it creeps, and I have to blip the throttle to find the gears! 

  Needs to get it sorted before the trip to London.
Richard has suggested a few possibilties, and as he said some are very possible and some unlikely. I'll have a go at investigating them and let you know how I get on. In the meantime I'm open to suggestion!