Just a humorous, totally impractical tip. Many years ago when dogs ran free in my home town, I'd take my nephews and nieces out for a ride. When a dog would spot us, I'd slow down to about 2 miles and hour, until the dog was just walking slowly beside the car, looking utterly mortified. What if his friends had seen him? Soon, he'd just kind of slink away, and my nephews and nieces thought it was the coolest thing going. Forget impressing them by racing down the road. Embarassing dogs was a lot more fun.
We did have a dog that chased cars and motorcycles so I got a friend of mine with a motorcycle to let me ride on the back, and when out dog came racing after us, I threw a bucket of ice water on him. That seemed to do the trick.
I wouldn't recommend either of these approaches seriously, but it sure was fun watching the expression on the dog's faces..
Jerry