There is a link on here about it somewhere, but as a quick reminder next time you change your clutch cable you will have to totally remove the front sprocket cover where the lower end of your clutch cable sits.
Before putting it back together, pop off the rubber bung on the front of the cover and fill the hole where the adjuster nut is with spray grease, i've always used White Grease, but each to their own.
Then using the spring loaded mechanism that the cable normally sits in, keep pumping it and it will draw in the grease and lubricate the bearings inside.
Just keep doing this until you know there's plenty of grease in there.
The bearings inside can get completely forgotten about, if you even knew they were there, but after plenty of greasing you'd be amazed how much smoother it can make your gear changing become.
Here's the thread if you've not read it before, it makes good reading and is a simple but very effective thing to do.
http://foc-u.co.uk/index.php/topic,10124.msg105264.html#msg105264