Well we usually refrian from giving jetting advice, as every single bike is different. Mine ran fine on Mains up near 190 with only a few mods, others run better with mains only a size or two up from stock.
There's so many things which can affect the jetting, and getting it wrong is such a pain in the bum!
Still, we all had to learn sometime, so as long as you're aware of what to look for on a plug chop, and go about it sensibly, then I'm sure you'll be fine.
I certainly wouldn't start leaner than 145. It might cost you a few quid buying a selection of jets, but I guarantee it'll be cheaper thana new piston and a replate...
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