Although disc brakes were allowed in 2016, Tom Boonen opted against using them this season. In Paris-Roubaix, he rode a rim-brake Specialized Roubaix SL4 to a heart breaking second behind Mat Hayman (Orica-GreenEdge).
Following that race, the UCI stopped the disc brake 'experiment' after Fran Ventoso (Movistar) suffered a deep gash to his leg that he blamed on a disc brake rotor.
Now that disc brakes are back in the peloton for 2017, Specialized has made a Venge disc machine just for Boonen. The Quick-Step team posted photos of it on Twitter today.