So seemed simple, change the cable... So i did that, and I have already got it at full extent of adjustment at both ends

Yet today i was having the same problems, At the lights i had to hold the break on to stop the bike rolling off, and it did die occasionally and i had to shove it to side of the road, which is bloody hard work when the clutch won't disengage!!!!
So basically what do you think i could do?? I was thinking of re-routing the clutch cable, so it was effectively shorter and so would disengage the clutch.
The friction plates were changed about 2 months ago, at which time i checked the steels and they were fine.
Another thought....any chance it could be the oil? Its semi synth castrol designed for bikes......
Cheers for responses people