Was in Prudhoe in June on a 2003 FJR.
We originally planned to ride fairbanks to Coldfoot, then overnight and continue to Prudhoe the next day. However, because the weather forecast was excellent for two days and then a forecast of rain, we adapted our plan and departed Fairbanks at 4.00am and arrived Prudhoe early evening. I'd advise you to be adaptable as the weather and road conditions will have a big impact on your progress.
I ran the FJR with Michelin pilot road 2s. Held up very well mileage wise. Picked up quite a bit of damage to the exhaust and belly pan plastics due to big rocks clanging off the underside of the bike. Running at 40-50 mph was fast enough for me on the FJR - seemed to develop a horrible weave at higher speeds on the gravel. Of course, some sections we were down t0 less than 20 mph. Stay off the brakes, use the gears and be prepared to give a handfull of throttle when the front wheel starts to bury itself