Energizer Trail Pup (Motorized Bike)

Our Smooth Coat Boarder Collie (Henry) goes for his 2nd run with the motorized trail bike.
Because we are both new at this we only took short sprints. It's hard for me to tell if he has endless energy, or if he is on the verge of out running himself.
If keep him next to me he will obey my "back" commands, but getting him to slow down takes allot of effort at the moment.

motorized bike,motorized bicycle,motorized trail bike,motorized mountain bike,trail dog,bike dog,bike trail dog,boarder collie,smooth boarder collie,smooth coat boarder collie,motorized bike ride,motorized bike off road,