Thanks all for the reponses.
I have the optional 10" rear wheels which is making the wear situation worse as noted by Colin.
To Tron20, I originally had bad wear on the inner 15% of the front pair too but a local tyre fitting garage agreed to set up the geometry and camber (all the national chains wouldn't touch it!!). I then got 45K out of the next set of Conti-sports! Brilliant. However, the rear tyre wear problem persists.
The local tyre garage I use have suggested I get the rears set up by a specialist like Protyre in Bristol. Has any one else done this and were the results positive?
Cheers,
Marco.