Do not use KC motorcycles in Hove unless you take the wheels in loose to them. They are expensive though do a good job
TPG Motorcycles
Unit 3, Freemans Road
Portslade
East Sussex
BN41 1SL
Tel: 01273 420045
are closer to you. Real back street bike shop - they are straight out of the 1950s - god knows how they stay in business. Do MOTs and can get most tyres. You have to go off road to get to them!!! The road to them is really rough. Google a search to get a map as they are not easy to find if you have not been there before.
I buy my tyres from here
http://www.mynetmoto.com/
Good service and good prices especially if you buy three tyres at a time