If you pay attention, you will notice that for most motorcycles on the road, especially the scooter, the front and rear wheel sizes are often not the same.
Specifically, the front wheel usually has a larger diameter, but the width of the tire is narrower than the rear wheel.
In fact, rubber tires began to be used on motorbikes in the 1800s, when the front and rear wheels were the same size. However, since the 1900s, professional tire manufacturers have shown that the same size of front and rear tires is not optimal for operation.
To bring the best performance, the wheels often have mismatched sizes between the front and back, specifically:
front rim size is bigger than the rear rim
The front wheel on a motorcycle is a pressure wheel and has a navigation function, so when the rim size is bigger, the car has better navigation, especially the flexibility to operate on the uneven road conditions (such as sidewalk climbing, etc.). Of course, manufacturers also calculate how big the tire size is enough, not just the bigger the better.
In addition, the smaller size of the rear wheel increases the space between the wheel and the saddle - a condition to bring the trunk more spacious, so most scooters have wide trunks. bigger front wheels like the rear wheels like Honda Lead (with 37-liter trunk) with 12-inch front wheels, 10-inch rear wheels; Yamaha Acruzo (trunk 37 liters) has 12-inch front wheels, 10-inch rear wheels ..
And one more thing, this difference in size also helps to reduce the shock on motorcycles with longer journeys, which helps the car to be quieter during the operation, helping riders to be comfortable, especially on the roads. long road.
Rear tires are usually wider than the front tires
While the front rim size is bigger than the rear rim, the rear tire is usually bigger than the front tire. It can be clearly seen that many vehicles such as Honda SH scooters with 100mm front tires, 120mm rear tires; Yamaha Exciter has 90mm front tires, 120mm rear tires ...
The reason is that the rear wheel is usually the main load bearing wheel on the motorbike, so the greater the area of contact with the ground, the better the stability and balance of the vehicle during the operation. In addition, wide rear tires also help the car have a good fulcrum to create stronger traction, better for the acceleration process for motorcycles.
And aesthetically, the large rear tires often give the car a boost and luxury, which is why most high-end scooters often have rear wheels called "fat wheels."
Naturally, the navigational role, the narrower the front tire is, the more flexible it is to change direction. However, the front wheel needs better grip (with more spines and deeper grooves) because when operating on slippery roads in the rain, if the front tire is worn it is easy to slip and endangering operators. This is also the reason that regular disc brakes and ABS brakes are often preferred equipment for front wheels.
Although the front and rear wheels have different roles during use, users should pay attention to periodic maintenance for both to ensure safety.
source : http://danviet.vn/xe360/tai-sao-2-banh-tren-xe-may-lai-co-kich-thuoc-khac-nhau-1076258.html