First, the hub is not bigger, the better
The automobile wheel hub is a cylindrical shape of a tire-mounted metal part mounted on the shaft. Wheel hubs vary in diameter, width, molding, and materials.
In the case where the outer diameter of the tire is constant, it is necessary to change the tire with a high flat ratio when changing the large rim. As a result, the lateral swing of the vehicle is small, the car will be more stable when opened, and the feeling when cornering is also It will be lighter. But the price is that the shock absorption performance is greatly weakened, and a small bump will be clearly transmitted to the car, and the comfort will definitely be greatly reduced. In addition, the flat and thin tires are weak in resistance to external forces, especially when they are sharp and sharp.
If it’s not for the car family, it’s just for the appearance of the wind, there is no need to change the tires of the big wheel.
Second, not all large wheels can improve performance
Many people think that widening a tire with a large rim will improve performance. This view is wrong. The size of the tires and rims will directly affect the inertia of the wheels. If the inertia increases, it affects both acceleration and braking. If you want to increase the performance while increasing the rim, you should try to use a lighter rim.
Third, the shape of the wheel itself will also affect the performance of the car
If the shape of a rim is such that the weight is concentrated in the center of the rim, the inertia generated is smaller when the wheel is rotated; otherwise, if the weight of one rim is concentrated outside the rim, the resulting inertia is even more Big. Therefore, the choice of rims, not only depends on the total weight of the rim, but also depends on where the weight is distributed. The farther the weight is from the center, the worse the performance.
Fourth, the disadvantages brought by blindly choosing large wheels for family cars
On the family car, 99% of the alloy wheels are the most common casting process, the large-size wheels are almost heavier than the smaller-sized wheels, and the thin tires cannot balance this weight. This will lead to an increase in the quality of the unsprung, which will have a negative impact on fuel consumption, handling and comfort. This is also mentioned above, and lightweight wheels are used. Another negative effect of low flat rate tires is ride comfort. Therefore, friends who want to change the wheel hub should also consider the cost of this.
Therefore, the manufacturer will match different wheels and tires according to the torque and horsepower of the car. For example: 1.5 Fit with an 18-inch wheel is not too fast to waste oil, because the torque is not enough, on the contrary, the 3.0T Audi A8 with a 14-inch wheel is also a waste of power and wasted oil. Therefore, the size of the hub and the width of the tire must match the torque and horsepower of the car. It is a waste of oil and power to go down or up beyond the matching range.
Five, insist on changing the wheel, how to choose the wheel?
1. First choose light quality (under the premise of brand safety)
2. Select the mass distribution to the center
For points, it may be important to talk about why you should choose the center of the mass distribution. Before we do this we need to understand a physical formula that affects the rotational motion:
T = I x a, T is the torque (torque), I is the moment of inertia, and a is the angular acceleration (the rate at which the rotational speed increases). Among them, I, the popular saying, is the ability to resist external interference when the object is rotated. Related to the mass distribution of the object. The farther the mass is from the center of rotation, the larger I is, the greater the moment of inertia, which affects performance.
Sixth, what do you need to pay attention to when you change your big wheel?
1, pay attention to observe the internal structure to prevent stuck
Many people only notice that they don't touch the outer sheet metal when they change the wheel hub. However, if you take down the wheel and take a closer look at the structure inside, you will find that many places are very easy to get stuck, especially after the car is opened. It will compress instantaneously on the bumpy road, so leave a margin in advance when loading the hub.
2, the brake caliper stuck to the rim
In today's cars, large brake calipers are often used for safety. In such cases, if the rim offset (offset value) is insufficient and a properly designed rim is used, the rim will be stuck to the brake caliper. After the installation is completed, if there is friction in the wheel when driving, care should be taken to replace it in time.