The Quick-Step Floors cyclist crashed on the Maing to Monchaux-sur-Écaillon cobbled sector, with dramatic photos of the incident showing that his stem and steerer tube had detached, sending Terpstra over his detached bars and on to the cobbles.

“The rigid steer cartridge is an aluminium part connecting the steerer tube and the stem, supporting Niki’s feedback that he wanted the bike to be fully rigid for the race,” said Mark Cote, Specialized’s leader of global marketing.

“We made a pre-production model back in January for him to try out in a few test rides. After that we went back to Morgan Hill and engineered another improved model and brought five new rigid cartridges back to Europe.

“The problem was that there was a miscommunication on Specialized’s marketing team and the original pre-production sample never got taken away from Quick-Step, and the engineered samples never got put on any of the bikes. That meant Niki raced with the original pre-production model that never went through full safety testing, and that’s the part that failed.”