Pneumatic, or air-filled, tires have been around since the dawn of the automobile and were originally designed to yield a better ride on streets originally made for horse-drawn carriages. However, pneumatic tires have since made their way onto practically everything that moves, from wheelbarrows and aeroplanes to tricycles.
Better Wear Resistance
While most tricycle-aged children aren't big enough to present a serious wear issue for plastic tires, even occasional usage on the rough surface of the average driveway can quickly wear away at plastic wheels. If your tricycle uses hollow wheels, such wear can easily weaken the tread surface to the point of cracking and failure.
Easier on Surfaces
If your child tends to ride in the same pattern back and forth on your driveway, the plastic wearing off of the wheels can embed in the hot concrete and leave unsightly marks that are all but impossible to remove without resurfacing. Additionally, hard plastic wheels can scratch the polyurethane coating on wood floors; laminate floors don't even stand a chance against them. Air-filled rubber or silicone tires can leave scuff marks on hard floors, but they'll buff out.
Better Performance Off-Road
If your toddler has a yen for the outdoors, odds are that she enjoys riding her three-wheeler outside. Air-filled tires will deform a little under load, spreading the trike's weight out over a wider area and helping your child to glide over grass, leaves and soft soil instead of sinking in. Hard plastic wheels will cut into the ground like a set of pizza cutters, making forward movement and steering more difficult. Additionally, this digging in can result in a tip-over if your future race car driver likes to take the corners at speed.
One-piece plastic wheels are cheap to produce, making them the roller of choice for bargain-priced trikes. However, the fake tires cast into most plastic wheels aren't anywhere near realistic. While your 3-year-old may not care much about the finer points of tricycle styling, chrome or painted wheels and real rubber tires will look a lot better in pictures.
Cast plastic wheels may not use very strong centre sections. Air-filled rubber tires and metal wheels are inherently more resistant to weathering, damage from UV radiation and whatever impact damage the tricycle might sustain during use, storage or transport.
If you've grown tired of the freight-train-like rushing on your hardwood floor at 7:00 a.m. every Saturday, you may find the solution in air-filled tires. While rubber may squeak a bit, it sure beats the sound of hard plastic rolling around.