Brake Binding

[hardnutdvd]

I noticed yesterday after half a mile of riding that one of the front brake discs was extremely hot (far too hot to touch) whilst the other was stone cold..
I'm assuming the pads are rubbing on the one disc as the wheel rotates, although the wheel does turn when its off the ground and does freewheel on the road both when coasting with clutch in and pushing it along by hand..I can also hear a very faint rubbing of the pad on the disc.
there is no sign of fluid leakage on any part of the braking system and it stops as it should when the lever is pulled.

I have done some reading about generally servicing the calipers but has anyone got any tips/advice for a complete novice to working on the braking system. it looks fairly straightforward, or will i be pulling my hair out?

if i do the one caliper (clean + new seals) am i right to assume that both calipers will still need to be bled?

[hardnutdvd]

just got back from the garage that fitted new front tyre yesterday...
when the guy had put the wheel back on and tightened everything up yesterday, the way he'd done it had caused the disc to constantly rub (not sure how)
the pistons were returning into the calipers ok when he had it off today so they are working as they should be...

another guy today loosened everything off, tightened it all up again and seems to have sorted it,