I struggled to get my Imola set up with a PHBH 30mm and revvy exhaust, even had it dyno'd with little success. It was very rich low down and any attempt at getting rid of it lead to a the plug being too light for my liking. I was advised to use a Mikuni TMX27mm by one of out German cousins and he gave me the folowing jetting to use.
Engine: Imola 186 kit.
Carb: TMX 27 MM Mikuni, ran open mouthed.
Set up: Needle 5EL68-3 [that the factory needle from a TMX30]
Pilot 20
Main 250
Power jet 60
Exhaust: ScootRS pipe.
Bit of effort [at the time] to track down the right needle and jets but fitted it and never touched it again. The only issue I had was modifying the length of the choke cable.
Ran clean as a whistle from day one, went much faster, did 55mpg and far less spit back than the Delly. I'm planning on using it on a Monza 225 though I'll start a bit richer on the main and probably use a breath sweet filter.