As I have posted before (many times, sorry to be so persistent guys), the single best change I made to my Caterham to date was new RA1's. And I have made a LOT of changes.The car's handling was transformed. I have put 10-12K miles on them, including many track days and they are still going strong, tho visible tread is nearly gone, so they are dry tires only.
Steve(BBall):
Any problem matching your lovely Pansport-type wheels to your Caterham's bolt pattern? Who manufactured the wheels? Do you have the 3.90 diff? If so, does the engine spin like crazy w/the smaller diameter wheels (My car has 15" wheels and 205/55 tires, so 13" tires wld basically subtract a gear, and make highway cruising difficult/noisy).
Mike M.