bouncing temp gauge

[Darkk_Calais]

i have just changedanged my radiator in my vt and now since then ive noticed them temp gauge will sit just on a quater for a while then creep up to half way between quater and half then go back down then back up and so on its a pretty fast creep propably every half a k it will be up then down again, ive bleed the system 5 times so there is no air left in the system.
Anyone have any idea why it could be doing this? The car is a supercharged 6 with the 3 bleeders.

[ACEMonkey]

It could be bad connection at your temp sensor. Give the connectors a clean with some contact cleaner and see how you go.