Does he run free or on a leash?I just came back from a nice bike tour with Ollie, he loves it and can't get enough, but I still have to go easy as he will be only a year old on Saturday.
I used to take my GSD on the mountain bikes trails(off leash).
She stayed with me rather well, but yeah, had to watch not to over do her.
I used to ride with the brakes on to slow me down without decreasing my workout.