They may not do any pedalling, but the outcome of an Olympic road cycling medal – and even the life of a competitor – could be their hands. Bicycle mechanics play a crucial role in the dreams of top-level cyclists. If the job is not well done – if a brake or gear is not perfectly tuned, if a wheel is not properly fixed, if a tire does not have the correct calibration – it could result in a cyclist failing to finish the race or even suffering a serious accident.

According to mechanic Mateus Ferraz, who was part of the neutral assistance team for the Rio 2016 road cycling test event on Sunday (16 August), technological advances only increase the responsibility placed on bike mechanics. Road racing bikes today are made of carbon fibre and gears are regulated by computers. Ferraz must check the torque of 20-30 screws per bike two times each before delivering it to the rider or placing it on the rack on the safety vehicles. “A carbon fibre bike is more delicate than one made of aluminium or steel and we cannot tighten the screws very much, or we risk damaging the bike,” said Ferraz.

Check out this video made during the Rio 2016 test event (click on the options icon to select English subtitles)

Gears deserve the same level of attention. High-performance bikes are becoming more like cars, with adjustments made by computer. The frames to which all the parts are fixed are tailored to each cyclist. “When we travel we bring five different frame sizes to suit the tallest and shortest athletes,” Ferraz said.

Once the race gets underway, mechanics travel as co-pilots in the safety cars to help with on-the-road repairs. The speed of changing a flat tire can make the difference between a medal or going home empty-handed. In serious cases, a replacement bike can be required.

Spanish safety car driver Julio Gallego is a veteran of international events who has worked on the Tours of France and Spain. “Once we had a big crash, with many cyclists,” he said. “After attending the most serious cases, we looked at the cars and… where are the bikes? The cyclists had helped themselves and sped off!”

The closeness of the professional relationship between cyclists and mechanics often becomes a friendship. “Cyclists invite their mechanics to barbecues at their homes,” said Brazilian cyclist Eduardo Oliveira. “They ask them to be their best men and invite them to their children’s christenings. They become part of the family.”