The crack happened under the eyes of the public: During the spring race Le Samyn the handlebar drop of Mathieu van der Poel’s Canyon Aeroad broke. Miraculously, the cross world champion did not go down. But the missing handlebar piece and the loosely dangling shift brake lever reminded us that carbon involves certain risks. Even companies with a lot of technical expertise like Canyon are not invulnerable to damage to their products. The handlebar breakage presumably due to the interaction of the shift brake lever fixing to the carbon handlebar, is however an unusual incident. Forks break much more frequently.
This year for example during the Omloop Het Nieuwsblad race. The Factor Ostro VAM’s fork of EF pro Tom Van Asbroeck failed above the head tube - luckily without severe fall. Bike manufacturer Factor analysed the damage and identified a defective steerer tube expander and improper mounting as cause. In 2019, the Swiss pro Simon Pellaud went down during the Tour du Doubs when the fork of his Bianchi Specialissima broke during the sprint. Pellaud fell, but was lucky and did not injure himself seriously. He wrote on Twitter that he would never forget the moment when he suddenly held the handlebars in his hands during pedalling, but that he made it across the finish line before he went down and was able to avoid the barriers. He also published the photo of his broken racer but deleted it soon. Copies of it are still available on the internet today.
Is this a random accumulation of problems with carbon components? Rather not. The number one problem area on road racing bikes is not the handlebar, but the steerer tube, says graduate engineer Dirk Zedler, who as a tester and expert witness has an overview of what happens when bikes break (see interview). Google also finds far more hits on broken forks than on broken handlebars. Zedler says: “Although the products have become safer all in all in recent years, it’s in particular the stem clamping on carbon fork steerer tubes that still involves risks.”
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Author: Robert Kühnen
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