There are so many reasons to cycle.
"It helps me lose weight."
"I need the aerobic exercise."
"It makes me feel good."
"It's helpful to the environment."
"It gives me 'biker legs,' which are a 'chick magnet.'"
"I love being outside."
"I meet great people."
"It's cost-effective (a term my wife has trained me to use in place of, 'cheap.')"
But I think it secretly boils down to this, that when you start pumping on a bike, you enter another dimension. It continues even after you finish. It's addictive (in a good way.) For some reason, you are in this wonderful "dimension" while everyone else is on another level.
It's just the reward that comes from doing what you love: cycling.
When you find something you love, you just want to tell everyone.
You want them to experience it, too. You are disappointed when people don't get it. But you know something they don't. So nothing stops you from gleaning all the benefits for yourself.
In the end, this is the ultimate lesson: a life lived that demonstrated something of great value to others by example.
No pressure tactics, no holier-than-thou stuff, just, "Here I am, see for yourself. If you like what you see, it's yours too, no charge."