If you're wondering what 55+ mph on a bike looks like then take a look at this video of our descent on the spectacular Col du Glandon (the same route the pros will ride July 19, 2013). It's from Bryan's GoPro camera mounted on his handlebars - that's me ahead of Bryan for a good part of the descent.
https://vimeo.com/70076247
Click on the HD in the lower right of the video screen to watch it in stunning High Definition.
Enjoy!
Jonathan