thanks for the advice re the forks and gear ratios.. the wrecker i spoke to said the R, SE and SP engines all had different ratios (which i didn't think was the case). I think i may just leave the engine for now and get it cornering nicely first

i should have mentioned that there's not much you're legally allowed to do engine performance modifications wise. can't touch engine internals, basically all parts must be from roadgoing versions of the same make/model. The rules are a lot different to the formula 250 series you have over there. the 250's are lapping about 10 sec a lap + slower than 400's on a 1:50 track