wicked will

Many thanks to Phil & Kevin, in response to Phil, good thinking, but as far as I can tell the XJ900s rear brake is rigid as opposed to floating front brake design. Kev, thanks, had not considered that one, fluid has been running freely through the brake line when I stripped the caliper and I can see some movement (both directions) at the pistons when footbrake is operated. It just does'nt seem to be enough movement to be allowing the disc to run freely enough. Will get back to you on this one.

Rear brake 'dragging', whether brake is used or not, disc getting very hot, ie; you cant put your hand on it. Caliper has been stripped, cleaned, fitted new seals, replaced anti-rattle shims (which were missing, presumed discarded by previous owner), master cylinder stripped to check for sticking piston, broken spring etc., fluid changed for new. Disc maximum runout is .15mm (approx. .006" in english money) mine is .2mm (.008"). .002" over, can this be enough to generate this amount of heat? or is there something else I can try before blowing a ton on a new disc. I'd be grateful for any good advice. PS; Please dont ask if my foot is resting on the brake lever. Wicked Will.