The mechanic Chin Ho Kelly visits is played by Robbie Knievel, son of late motorbike stunt legend Robert "Evel" Knievel who is referenced by Danny Williams in the beginning of the episode.
The Tough Mudder race: The team shirts say Five-0Hana, 'ohana' meaning 'family' which is a major theme of the team since inception. The numbers on the Five-0 team shirts are... Steve 110, Danny 111, Chin 112, and Kono 114. But no 113. The reason there is no 113 is cause it is believed that 13 is a unlucky number.
The episode title roughly translates to "big lie".