I do it alot, beats the hell out of walking
I try to keep to 8-12 mph, how accurate that is I dont know, just on one of them bike computer thingys.
When you start, stop every 1/2 mile or so to check the dogs feet, if they are getting saw then WALK them home. I attach the lead to my seat, making sure that the dog cannot go far enough ahead to get infrount of the wheel. I also always bring a bottle of water for the dog (and me )
It really is good fun, much better than road walking them. Just dont push it, start of at about a mile max do that for a week then abit more and so on. I do