What is the difference in hub size? What are the differences in driving and vehicle wear and tear? Why some models with large hub high, and low with small hub? Is a big hub always good? Can I change a car back and forth?

It is widely understood that the big hub is not too bumpy, the small hub will be more bumpy, but the handling will be better. But a lot of people may not understand, why there is such a result?

In the process of driving, the car is affected by many factors, on the one hand, when turning, on the one hand, is the centrifugal force, on the other hand, is the smoothness of the road. So this car is not going in the direction that your tires are actually pointing in, it's going sideways. The tire has a very important parameter called side stiffness, and there is a very important factor in the side stiffness formula, which is the flat ratio.

The thinner the tires are, the more likely they are to increase side rigidity, which makes it easier to drive the car in the direction you want to go. So when we look at some cars, we feel that the handling is not very good and the steering direction is not very accurate. In fact, it is not necessarily the design problem of his car in some aspects. It may be caused by the small size of his hub and thick tires.

The higher the flat ratio is, the thicker the tire is, and the better the conditions for adapting to the complex road surface are. This is why all off-road vehicles have high flat ratio.

Of course, the high flat ratio results in a very thick tyre, which, while improved mobility and adaptability, reduces handling and high-speed stability. Because of the long contact between the rims and the ground (the tire side is thick), the handling is reduced.

When the flat ratio is very low, the rim is almost in direct contact with the ground, resulting in a large tire load, increased damage rate, decreased comfort, shock absorption and engine load increase.

But handling will improve accordingly, and so will stability.

Therefore, the choice of a relatively thin tire and large hub can be very significantly improved vehicle handling. Of course, it's not all upside. If you have a thin tire with a big hub, it is very easy to knock out the whole tire on a broken road or some small bump, because it is very fragile.

There is also the problem of bumping with large hubs. Because tires are harder, they are less able to absorb bumps and shocks. Big wheels and small wheels have their own advantages. If you're buying a car that emphasizes fun to drive, you can go for bigger rims and thinner tires, which will help improve handling. If you are a household, you don't need to be so intense, choose a smaller wheel to sit more comfortable, this is a big difference between them.