What constitutes properly “mounting” and “dismounting” the bicycle?

Mounting the bicycle:
When arriving at the mount line, make sure both of your bicycle tires are fully across the
mount line prior to mounting your bicycle. The point at which “first mounts the bicycle” occurs when the participant’s leg crosses the vertical plane extending up from the top bar of the bicycle. 

Dismounting the bicycle:
When arriving at the dismount line make sure you dismount your bicycle prior to your front bicycle tire touching the dismount line. Dismount shall be defined as the point at which the participant is completely off the bike and both feet have touched the ground.