Clunking sound when setting off?

Hi

Sometimes when my Clio 197 has been sat over night and I get in and after it has warmed up I go to pull off and hear one loud clunk coming from the rear? It feels like my rear disc has just unstuck itself? Any ideas what this might be?

Thanks
 
I think you answered your own question. Common enough if a car has been
parked a wile and discs get a bit rusty.

Leave the handbrake off the next time if safe to do so and see what happens.
 
Yes, very normal - when was the last time that the rear brakes were stripped and cleaned/re-lubed? If they're due a seeing to, then that could be a potential cause of the sticking too.

EDIT: also, moved to correct section.
 
Mine does it too after its not been driven for a while. I dont see it as a problem. My 205 GTI used to do it and I put it down to having discs on the rear and not using it enough. Doesnt do it in the summer only when its wet or its rained.