During the Games in Rio this curiosity happened to occur even twice within a few weeks, during the Olympic and the Paralympic Games. And this under professional conditions during the world’s major sports events. Concerned by this incident were track cyclist Kristina Vogel loosing her saddle during the final spurt and Hans-Peter Durst whose saddle had already loosened right after the start.
Bicycle expert Dirk Zedler from Ludwigsburg gives an explanation. Vogel’s track bicycle is an extremely lightweight carbon model. If fine cracks in the carbon occur as a result of too much pressure, for example due to overtightened bolts at the seatpost, the material becomes instable.
On Hans-Peter Durst’s model the saddle is mounted like on a common bicycle. It was designed and assembled by frame builder Sven Krautscheid: “The saddle is fastened with two bolts. One of these bolts broke”, he explains. According to Krautscheid, due to a material defect.
A problem that often occurs, says Dirk Zedler, not only for professional riders, but also for the elder woman riding to the green market once a week. “The saddle bolts must be tightened properly. This is best done by using a torque wrench”, recommends the expert. This is something that is neglected by many cyclists. But once a bolt starts wobbling, it wouldn’t take long until it breaks. “In the case of Hans-Peter Durst the breakage can also be due to the assembly. That is to say when a bicycle is often disassembled and reassembled”, explains Zedler. He is happy that the athletes remained uninjured: “Their reaction was good, because they are professionals. Normal cyclists would have fallen with serious consequences.”
Author: RENÉ LAUER