Bicycles don't burn gasoline or other fossil fuel. They burn fresh carbohydrates, not fossil hydrocarbons. Fresh bicycle fuel is being produced right now in the age of humans by fresh green plants eating the sunlight. This photosynthesis removes carbon from the atmosphere instead of adding carbon like fossil burning does. When you ride a bike your own body is the motor and your food is the fuel, and this is the way animals have always moved. The bicycle uses traditional sustainable energy in a modern machine that multiplies the biped body's efficiency for forward movement.
Dinosaurs, birds and humans walk on their hind legs, but ostriches and dinosaurs can run much faster than people can. The bicycle gears and the size of the wheel allow a human or a dinosaur cyclist to move five or ten times faster than by walking. So a human on a bike can keep up with a running dinosaur, and a dino on a bike can actually get away from a police patrol car chasing it.
Humans are playful mammals and can really enjoy riding a bicycle in a park or
even to work. They get just the
right amount of exercise and stay healthy by riding a bike for all trips
less than 5 km.
They can be happy knowing that they are not adding to the extinction problem that we old dinos know totally stinks.