Alex Lord, 26, who is from Maidenbower, set off on the epic challenge from the Cornwall landmark on June 16.
Along with friends Rob Fenwick, from Kent and Jamie Tyson, from Surrey, the determined trio arrived at the finish line in six days, nine hours and 35 minutes.
They are now waiting to have official confirmation they have beaten the existing record of six days.
Despite four punctures and four hours sleep most nights, the trio cycled through every challenge that was thrown at them. Alex sat at the front and manned navigation and braking. At one point they achieved an impressive top speed of 52mph. They have so far raised £3,900 for their three chosen good causes, the NSPCC, The Early Birth Association and The Lords Taverners.
Alex said: “It was an epic challenge and we are so proud. I have done a half iron man challenge and this does not compare.
“We had some tough times and the sleep deprivation started to get to us towards the end. We were going to sleep at midnight and having to get up at 4.30am to start riding. But our friends and family just kept us going with their messages of support and the weather was kind to us.
“And we had lots of support along the way and many people were fascinated to see us on a triplet bike.”