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 DR350