Had a free hour waiting for my mates to get ready to do a loop into Italy from Guilestre so rode up and down this route a couple of times. The lower section has moe varied radius corners and the upper section long high speed straight/sweepers. Exellent fun.
The road from Guilestre to Risoul 1850 is built for coaches to take skiers to Risoul in winter. In the summer months there is very little trafic. The road is wide with long radius hairpins about 1 km apart and superb high speed corners in between. Its a dead end so you have to ride back down - hardship!