Here are eight solid reasons to ride a bike:
1. Bicycling is fashionable.
2. Bicycling improves physical and mental health.
3. "It's getting hot in here," say U.N. scientists (http://www.ipcc.ch/). Bicycling results in less pollution and fewer GHG emissions than driving a car. No kidding.
4. Bicycling is convenient - For short trips, bicycles simply can't be beat. They are often faster than taxis, buses, trains, and personal automobiles. Remember to factor in the time you spend looking for a parking space.
5. Bicycling is safe - You're much less likely to injure yourself or others if you're riding a bicycle than if you're driving a car. Doubt it? Most studies disregard the fact that driving a car increases your likelihood of injuring OTHER PEOPLE.
6. Bicycling can reduce healthcare costs in America - It's true, ask your insurance company or your local epidemiologist. (Robert Wood Johnson Foundation)
7. Bicycling is fun - It just is. Try to deny it.
8. Bicycling is inexpensive - You are likely to spend very little on gas, parking, periodic taxes or registration fees, or insurance. You are also likely to spend much less on maintenance and upkeep than you would on an automobile. This remains true even if you regularly rent a car or truck, or use car-sharing (e. g. Zipcar).
The League of American Bicyclists likes bicycling for these reasons:
And here's one more thing worth thinking about: Social Justice.
It's really a combination of all the other reasons--a sort of meta-reason. Maybe I'll write something about this later.