Shaft, I know you are a proponent of leaner and leaner mains, but that didn't work in my case with Mikunis and twin-plugs. Different bike, carbs, etc., but going to 195's from 170's got me four more mph on the top end and I had to back off.
I started at 150's then moved my way up. The 160's would rev cleanly to redline buy I'd get a surge (only on a cold day, was absent when 80 degrees) when backing off from WOT as flow transitioned to the richer needle/needle jet. I went up 2 sizes to 170 and thought all seemed well. After discussing my jetting with someone who is very familiar with Mikuni/Airhead setups, I plugged in my 195's and instantly noticed more power. I still have some more testing to do with some other mains, but I'm running out of good weather here in MI.
Buy or borrow a cheap handheld GPS to get an instant and reliable reading so you don't have to rely on radar guns and charts.
89 BMW R100RS
97 Suzuki DR440
And away we go!