General:
The wheel consists of two fundaments parts, the core and the polyurethane (PU,) these two components are bonded together with an extremely strong adhesive.
Long ago, all cores were made out of plastic, but since 2007, more and more are being made out of aluminium. Though heavier, they are much more impact-resistant and fast.
Size:
1 : 100 mm
2 : 110 mm
There are 2 main sizes of wheel – 100 mm and 110 mm.
The 100 mm are lighter; the thickness of PU is reduced by 5 mm compared to 110 mm wheels. On the other hand, they are a bit slower, though usually rapidity mostly depends on the quality of the PU used. They are good for aggressive and dynamic riding.
The 110 mm are a bit heavier, but also a bit faster and more stable. They will also take longer to wear down. As a bigger wheel, is will also increase the ground clearance of the deck, making you feel higher off the ground when riding the scooter.
As you can imagine, the size of wheels is only measured in millimetres (mm.) Other wheel sizes include 98mm, 104mm, 105mm, 120mm and even 125mm, but these are extremely uncommon.
Weight:
Due to the fact the wheel is located at the extremities of the scooter; the weight of the wheels influences quite a lot its balance, especially the back wheel. With a light back wheel, the deck will have a much more responsive spin. On the contrary, with a heavy back wheel, the deck will be more stable in the air.
Hardness:
The hardness of a Wheel is determined by its durometer rating, a number between 0 and 100 and indicated by the letter ‘A.’ The higher the number, the harder the wheel. Scooter wheels are usually between 85A and 88A.
A hard wheel tends to be faster and more resistant to friction, making the PU harder to split. A soft wheel is grippier and will have more traction, offering a smoother ride.
Be careful though, since nowadays the wheel’s speed will depend a lot on the rubber’s quality. Indeed, wheels made in China do not match quality of European wheels, even after much development. Unfortunately, very few wheels brands are made outside of China.
In the case of a great quality rubber, even a 72A of exceptional quality would be faster than a poor quality 88A.