'There's no climb even close to this tough' – former US pro wins back 90km Strava KOM on world's hardest climb

American former pro cyclist Phil Gaimon has taken back the Strava KOM on Hawaii’s Mauna Kea, an almost 90km climb considered to be the hardest in the world.

Gaimon uploaded his file to Strava on Wednesday, showing he completed the 4,195m of elevation in four hours, 34 minutes and 10 seconds. The official ‘Waikoloa beach to Mauna Kea’ segment is 89.46km long, and climbs to the dormant volcano’s summit at 4,214m, starting on the island’s western coast.

Gaimon held an average speed of 19.6kph for the effort. His average power, according to Strava, was 271 watts.

“Not bad for an old man,” the American, who turned 40 this week, wrote on Instagram. In his Strava post, he described the effort as the “worst 40th birthday party ever”, adding: “There’s no climb even close to this tough.”

This is the third time Gaimon, who retired as a pro cyclist for Cannondale-Drapac in 2016, has earned the Strava crown on this Mauna Kea segment. He originally set the KOM in 2016 as the first person to clock under five hours. Gaimon’s time was then bettered by just 15 seconds in 2023 by now Tudor Pro Cycling rider Larry Warbasse, spurring him to reclaim it less than two months later.

Last April, the KOM swapped hands again, this time to an amateur cyclist under the username ‘elevin11’. Gaimon’s latest effort took nine and a half minutes off that benchmark.

The western ascent of Mauna Kea begins at sea level and has a deceptive average gradient of 4.7%, due to a flatter section in the middle. The final 21km are pitched at 9%. There is also a 10km gravel section at around 3,300m altitude.

Gaimon began his ride on a lightweight carbon road bike made by Arizona-based brand State Bicycle Co. For the gravel section, he swapped to the company's carbon all-road model.

The former pro credits Mauna Kea with kick-starting his YouTube channel, to which he began posting regularly in 2016 under the moniker ‘Worst Retirement Ever’. He now has 150,000 subscribers, and has said a video of his latest Mauna Kea KOM will come “soon”.

Last January, professional mountain bike rider Spark Moir Sears took almost an hour of the best women's time on Strava for the same segment. Her QOM still stands at six hours, 12 minutes and 51 seconds.