Those 450's seem to be handling the pace. I quite liked them last year and fully support them using 450's instead of 690's. They're lighter and I think the biking public can relate to them more. It's like a trail bike on steroids. Serious steroids.
The first few stages have been quite docile, but these guys are reaching insane speeds. According to Ultimate Motocycling the top speed reached by Quinn Cody on his Team Honda Europe 450 was 157km/h. I must say the roads are really helping these guys reach these speeds. Nice long, flowing and open.