Well, "Curious George Rides A Bike" is a classic. PC people point out that he doesn't wear a helmet, but he's a monkey for crying out loud. No one wore helmets when it was written. As I recall, in the cartoon series "Jacob Two Two", jacob rides a bike. And of course, Kermit the Frog is a legendary bicyclist.
I think that the best influences are not cultural, but rather physical. My two strongest early influences towards riding bicycles were tricycles and seeing my older brother ride down the block and around the corner on his bike. That sight alone promised untold adventures.
Get your oldest a drasienne, aka a balance bike. Here is
one vendor.
And of course, take them on rides with you. You might also check in the family forum.