Depends on how many cups of coffee I've had before the ride. And who I am riding with. I don't have any set rules, or any "usual" break times. If the ride has some good scenery, might stop to take a look, if not, just keep on going (unless coffee "rent" kicks in!) If it's extra hot/humid, there are more breaks than on cooler, less humid days. Too many factors to nail it down.