The island's Murdo 'Lightning' Morrison put in an incredible ride on the shorter 70 kilometre course, starting in Tobermory, to break the previous best time by around nine minutes.
The 14-year-old crossed the finish line in 2.16.59 as the only rider of 129 participating in the under 18s category on the shorter route around the north of Mull on Sunday June 4.
Weather conditions were near perfect for the annual event, which was first organised in 2011, with 329 riders taking part across the two courses this year.
Robert Lee was the fastest of 205 riders on the longer 140 kilometre course, finishing narrowly ahead of Alistair Simpson in 4.20.08.
Ferry issues caused travel headaches as around 100 riders who had signed up had to pull-out.
This year's sportive was organised by Joe Reade from Island Bakery and Jeff Adams, with Jeff impressed by Murdo's efforts on a tough, undulating route.
"Murdo Morrison was a late entry and he slowly pulled away from the other riders after I led them out along the road out of Tobermory," he said.
"He must have ridden up the first steep climb at around 24-25 km/h and was already about five minutes ahead of the next rider by the time he reached Salen."
Murdo's father Colin Morrison was tracking his son at the finish line and watched as he averaged around 30 km/h to arrive back in Tobermory in record breaking time, nine minutes ahead of the next rider.
Jeff added: "The guy who finished after him said he thought about asking him to sign his shirt afterwards because it might be worth something in years to come.
"Averaging that speed on a challenging route like that is hugely impressive because there are some brutal climbs on the shorter course, especially at Calgary and Dervaig.
"He has a huge amount of ambition and potential and has already won several duathlons and triathlons in his age group."
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