Thorn frame and forks.

[brummie]

It looks like an XTC classic frame to me. Same as mine, which can be found on the members gallery.
http://thorncyclesforum.co.uk/index.php?topic=13704.0

You're right it does and the colour of yours makes me smile.  Hope you've had some pleasant miles on it, must draw some comments.
Would I be right in thinking the XTC's would have had shorter chainstays than the more touring orientated models? Maybe that might confirm it.

The original XTC was lugged and was intended as a lighter- allround touring bike ( as opposed to the heavy duty offerings available in the shape of the Nomad and later EXP ) The XTC had a great review in Cycling Plus and sales took off. The lugless fillet brazed XTC soon followed with a tweaked geometry with slightly longer chainstays and clearances to allow fatter tyres. ( These frames were made by LA cycles to help meet the rise in demand ) The XTC SWB ( Short Wheelbase ) was introduced ( and made on site in Bridgwater ) which, as the name suggests had a tight sportier geometry and lighter forks with no Low rider rack bosses and had a lugged construction. These frames were all Reynolds 725, though later the Fillet brazed XTC was upgraded to Reynolds 853.

[Redswannie]

Yes I think your right, my frame looks just like this one, although in boring black :-)))).