A proposal was submitted for the classification referring to the different ways in which triathletes mount their bikes to start pedalling. Triathlon has been, and is being studied at length from different areas of expertise, such as physiology, biomechanics, psychology..., but rarely from an internal structure of motricity itself. This study concentrates in describing and classifying the motor behaviours that occur at the end of the transition areas, in front of the “judge’s line” (dismount line), or in the different ways that a triathlete can mount their bike. These are unique aspects of this sport, compared to other sports in which a bike is also used. In the T1, the last thing a triathlete does is mount their bike at the judge´s line (dismount line), after having gone across on foot, with the bikes at their side, or led across by hand, in a specific way. Our study is bassed on participants of 3 Spanish elite Championships and different age groups of different distances (407 triathletes). Eleven common and different ways were discovered on how to mount a bike when passing the judge’s line.