http://www.michigan.gov/documents/msp/MSP_2012VehicleTestBook_Web_PDF_375491_7.pdf
.42 (of a mile) to hit 120mph... had to have taken the trooper 6 weeks to catch up to them. I'm guessing they slowed down thinking he wouldn't be behind them while he was WOT the entire time.
Probably something like that.
Also, I doubt a 600 with a passenger would go over 140. A passenger makes a HUGE difference on a bike. The rider can't tuck properly, and that alone will take 5-10mph off the top speed...then add the added weight and aero restriction of the passenger's body and you're not going to outrun many cars on a flat open highway.
1000s will do 170+ with a passenger.