Michael Matthews rode on the as yet unannounced Giant Propel disc(Image credit: Josh Evans / Immediate Media)
Kittel likes the stiffness of the Vision Metron 5D bar as much as the aerodynamics(Image credit: Ben Delaney/Immediate Media)
The Venge wasn't designed for the the Vision bar, but it works(Image credit: Ben Delaney/Immediate Media)
SupaCaz bar tape from Anthony Sinyard, son of Specialized founder Mike Sinyard(Image credit: Ben Delaney/Immediate Media)
Shimano Di2 sprinter shifters peek through on both drops(Image credit: Ben Delaney/Immediate Media)
Specialized routes hydraulic lines through the frame and fork(Image credit: Ben Delaney/Immediate Media)
Dura-Ace rotors and calipers only recently became available(Image credit: Ben Delaney/Immediate Media)
K-Edge provides the chain catcher, although with Di2 shifting that is seldom needed(Image credit: Ben Delaney/Immediate Media)
Specialized's Roval CLX50 Rapide tubulars(Image credit: Ben Delaney/Immediate Media)
Specialized tubulars come in 24mm, 26mm and now 28mm(Image credit: Ben Delaney/Immediate Media)
The graphics even extend to the section of the down tube typically hidden by the front wheel(Image credit: Ben Delaney/Immediate Media)
The Venge ViAS has an hourglass head tube(Image credit: Ben Delaney/Immediate Media)
The original Venge was created as a disc bike, but then Specialized led with the rim-brake version as delays with pro racing put the Venge Disc on hold(Image credit: Ben Delaney/Immediate Media)
Staff at CERN blast electrons at each other and record the visuals of the impacts. The graphics here are a spin-off on that (Image credit: Ben Delaney/Immediate Media)
When the same brand makes the saddle as the frame, coordinating is relatively easy(Image credit: Ben Delaney/Immediate Media)
The 'explosive speed' theme continues throughout the bike(Image credit: Ben Delaney/Immediate Media)
A close look at the Shimano Dura-Ace 9170 shift/brake levers(Image credit: Josh Evans / Immediate Media)
Marcel Kittel aboard his disc brake Venge at the stage two sign on in Dusseldorf(Image credit: Josh Evans / Immediate Media)
Kittel ran 140mm rotors front and rear on the day(Image credit: Josh Evans / Immediate Media)
Michael Matthews also appeared to run 140mm rotors front and rear(Image credit: Josh Evans / Immediate Media)
Giant registered the new Propel frameset with the UCI in May this year, notably not registering a calliper version(Image credit: Josh Evans / Immediate Media)
Marcel Kittel rides with race number 101 for the Grand Tour(Image credit: Josh Evans / Immediate Media)
Marcel Kittel won stage 2 of the Tour de France riding a Specialized S-Works Venge ViAS Disc, becoming the first rider in history to win a stage of a grand tour on a road bike with disc brakes. The German sprinter beat Arnaud Demare and Andre Greipel in the bunch sprint in Liege, Belgium.
Kittel's win follows a spate of controversies and marks a key moment in the use of disc brakes in the professional peloton.
Disc brakes came into the World Tour peloton on a trial basis at the beginning of the 2016 season. But following the injury at Paris-Roubaix of Movistar rider Fran Ventoso that was allegedly caused by a disc, the trial was put on hold until the beginning of the 2017 season.
Marcel Kittel aboard his Venge Disc at the stage 2 sign on in Dusseldorf
However, following another crash incident in the Dubai Tour involving Team Sky's Owain Doull, Kittel stopped racing on disc brakes for the remainder of the stage race.
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Disc brakes were used prominently throughout the spring classics, but weren't involved any any big victories. In fact, the main favorites all chose to race on rim-brake bikes. Boonen used a pro-only rim-brake version of the Specialized Roubaix for Paris-Roubaix, his final race.
At this year's Tour de France, Michael Matthews (Team Sunweb) and Reto Hollenstein (Katusha-Alpecin) also choose to race disc brakes on stage 2.
On stage 2, it was reported that Kittel suffered a puncture early on in the stage and whilst the wheel change from his team took slightly longer than normal, it clearly didn't prevent the German sprinter from taking victory.
Following the stage, Kittel was informed he had made history by winning with disc brakes in the Tour de France.
"I actually wasn't aware that if I won I would get this title, but I said before that I think that it is a good step forward in technology development that we still have ahead of us," he said. "There is a lot of discussion around disc brakes, but in the end I was riding today on an improved version from Shimano. They're definitely better than the old ones (Kittel used non-series Shimano disc brakes earlier in the season). There's more adjustment possible and that's a big step forward and from now on I think, especially with the rain today, it will help riders to brake better. The control is good."
Specialized designer Ron Jones played on the CERN particle accelerator for the bike's graphic theme
Kittel also said that rider safety is a good thing.
"I hope that we find with the industry and the UCI, and especially with the riders together that we can get rid of the last negative thoughts about disc brakes, especially when it comes to safety," he said. "I think there is still support for it and I hope that they approve the request to protect the riders from a potential injury that you could have from a disc in a crash and the whole issue of changing the bike or wheel can be solved. I'm sure that if we can talk in the right way then we can find a solution to it."
Another issue that needs to be solved is rotor standards, as 140mm and 160mm options are currently used.The UCI has settled on 160mm as its standard, and told Mavic neutral support to supply 160mm rotors at the Tour. But Kittel and Matthews were both on 140mm Shimano rotors. Rollenstein, on a SRAM bike, raced with 160mm.
Take a look at the gallery above for a closer look at Kittel's Specialized S-Works Venge ViAS Disc, as well as the disc bikes of Matthews and Hollenstein.
The original Venge was created as a disc bike, but then Specialized led with the rim-brake version as delays with pro racing put the Venge Disc on hold
