Just adding the latest update to this thread for anyone who is interested.
I haven't changed the setup since the last post, but the weather has changed - The jets are now at 52.5(stock)/152.5(3 steps up from stock). The spacer is at 50% thickness.
I still had a bit of surging that I have been trying to figure out how to eliminate - but now think I don't need to.
So, the weather here has changed over the last few days, and the surging is gone! When I was doing the original carb tuning we were experiencing days of 35°C (95°F) with humidity at 100%. Now the humidity is still up around 95% but the temperature is around 25°C (77°F). I took the bike for a couple of long rides and it was just terrific!
It's great to feel the bike running the way I knew it could. It idles well, is smooth right through the throttle range, and if I open up the throttle it 'runs like a scolded dog' (as Lancer put it in an earlier post
)
I even had a chance to wind it out on a quiet stretch of straight country highway. I've read in some other threads the kinds of upper limits others found their bike could hit - and where the bike starts to struggle. I'd rather not talk numbers here but, let's just say, the bike didn't struggle.
I'm adding all these details because I learned a lot by reading other people's trials and tribulations, so I hope it's useful to somebody