Clearly, the folks shown below have not seen the episode entitled, Hot Wheels. If they had they might not be riding on the sidewalk when there is a perfectly good street right there. I am not sure how many kids shows these days include stories which revolve around bikes, but I somehow think they may be less prevalent than they were in the 1970s. I suspect that television, is a reflection of society, thus fewer kids riding in real life is reflected in what we see on tv. Unfortunate.
Anyway, there are a couple things going on in this episode - the gang visits a bicycle exhibition at the big museum, and Weird Harold takes on the responsibility of watching his uncles' bicycle for a month. Weird Harold thinks he knows all there is to know about riding a bike, yet even after warnings from the police, and while sidewalk riding with Rudy on the handlebars, runs smack into a pedestrian, sending her to the hospital. The message is clear as the boys visit a number of injured riders in the hospital - riding a bike comes with a responsibility to ride properly. You can check the episode, Hot Wheels here. As Bill Cosby used to say each episode, "...coming at you with music and fun, if you're not careful you may learn something before it's done. Hey, hey, hey."