Just an update. I never got round to getting throttle bodies but after 2 years of problems starting the engine from cold and a season of my lap times getting slower and slower culminating the other weekend with me throwing a strop and pulling off the track during my last race, I have stripped the carbs down and found I only had one accelerator pump jet working and two pumps out of three were seized.
The carbs were full of crap and after a good clean and some new seals and filters, the engine starts on half a turn from cold and runs and accelerates smoothly. Just have to check it on the road.
