Because kids outgrow bicycles faster than you can say “Don’t forget your helmet,”, you expect to replace them periodically. The most important factor in choosing a bike for your boy is getting the size right. While adult bikes are sized by frame measurements, bikes for kids are sized by wheel diameter and the child’s height.
Grow, Ride, Learn
At about 3 years old, your boy may be ready for his first two-wheeler with training wheels. With lots of practice he’ll develop sufficient balance, coordination, agility and start-stop skills to ditch the training wheels between 4 and 8. Most kids don’t have the strength and coordination necessary for hand brakes until they’re at least 5.
Between the ages of 2 and 4, a child whose inseam measures 14 to 17 inches can ride a 12-inch bike. Boys 4 to 6 with inseams of 16 to 20 inches typically do well with 14-inch bikes. A kid 5 to 8 with an inseam between 18 and 22 inches needs a 16-inch model. Boys 6 to 9 with 20- to 24-inch inseams can ride 18-inch bikes. A boy 7 to 10 with an inseam of 22 to 25 inches is ready for a 20-inch bike. Kids 9 and older with 24- to 28-inch inseams need 24-inch bikes.
Fits Just Right
For the proper fit, your boy should be able to lean the bike slightly toward him, slip his bottom onto the seat and straddle the bike comfortably with his feet flat on the ground.