Tyres vary in size, type and other parameters, and that’s why the weight of a tyre can be anything between 6.5 and 80 kg, if this happens to be a 24 inch truck tyre. Which parts of the structure weigh the most though? Are heavier models better? What does tyre weight and performance have in common? Read on to find out more about the different car tyre weights and the correlation between their parameters.
How much a tyre weighs depends on the designers' choice and internal construction solutions applied. All tyre manufacturers are obliged to respect the originally assumed weight. This is particularly important when a given tyre size is produced in different places.
What is the best tyre weight?
A lower tyre weight brings a few considerable benefits. The most important one is a reduction in the rolling resistance, which enables a lower fuel consumption rate for the vehicle itself.
It also similarly offers a decreased unsprung weight. This results in better performance for vehicles when braking, acceleration or undergoing precision steering maneuvers. It also helps to offer better driving comfort and longer suspension lifespan.
Because of these benefits, most manufacturers aim to reduce the weight of their tyres with every successive generation. This leads to better performance parameters for the product, as well as lower costs of production and materials for the manufacturer. However, this is not the case of high-performance tyres. Their producers often use advanced technologies and materials which may cause the tyre to be more expensive, even if it is still lighter. This is because tyre weight is a particularly important parameter for these tyres.
Reducing tyre weight
The development of the tyre world is clearly moving towards a gradual reduction in the overall weight of products. Most manufacturers choose to reduce the weight of their tyres with each new version.
There are some methods used to reduce the weight of tyres. They include:
- tyre slimming, i.e. reducing the weight of individual components (tapered banding, tread, tyre front, etc.)
- developing concepts of lighter tyre construction
- using lighter materials (e.g. steel or textile cords made of lightweight fibres)
Weight plays an important role in the production process of a tyre, mainly because of the pre-established standards for a particular model. There is, of course, the possibility of small variations within the accepted tolerance. These limits are usually stricter when it comes to approved tyres.
Off-tolerance tyres are treated as non-compliant and do not reach customers. Too little or too much weight in relation to the specified tyre may suggest the absence of certain tyre components, the use of incorrect compounds or the presence of a foreign body, or the lack of stability of the production process.
Average passenger car tyre weight
The market for passenger car tyres is diverse and the number of sizes available is very large. From 13-inch tyres for small city cars to more than 20-inch models for SUVs and sports cars. Tyres also vary in weight. Here are some examples:
155/70 R13 can weigh about 6.5 kg.
185/70 R13 can weigh between 7.0 and 7.2 kg
175/65 R14 can weigh between 6.5 and 7.2 kg
195/65 R15 can weigh between 8.2 and 9 kg
20-inch tyres can weigh up to 15 kg.
Tyres for sports cars are basically heavier - they often come with a thick tread with wide grooves, and the tread has the highest percentage of the weight of the tyre.
Truck tyre weight
Truck tyres are much heavier than passenger car tyres. The weight of a truck tyre can range from 30 kg to as much as 80 kg. It all depends on the diameter, as 24-inch wheels are usually the heaviest.
How much does a 17 inch tyre weigh? Approximately 35 kg. For another popular size (22.5 inches) it is 60 kg.
Tyre weight comparison
Significant differences in the mass of individual sizes result from the application of different solutions within a single model. After all, some tyres have to offer different performance for several types of cars, as well as withstand different speed and load ranges. Sometimes, within the same model and size, tyres have even higher speed and load ratings.
For example, extra load tyres (XL) will be heavier than the standard size. This is because they are equipped with additional components that strengthen their construction and provide a more massive structure.
Share of tyre components in the tyre mass
We've already found out how many kilograms the total weight of the tyres in each size can reach. Let's see how much each component weighs. Each radial tyre currently produced for passenger cars must consist of elements such as: wire with filler, butyl cap, textile cord layer (warp), side with an alloy belt, tread, headbands (steel bands and very often a screen with a zero degree belt).
Depending on the intended use of the tyre, its speed and tyre load index, the manufacturer's construction concept and production process, various elements can be added to the structure. However, it should be remembered that their share in the total weight is usually lower than the basic components and does not exceed a few percent of the total weight.
In the case of the basic elements, the largest share is represented by the tread - its weight accounts for approximately 35% of the total weight of the tyre. For example, a 205/55 R16 tyre can weigh 2.8-3.2 kg. The tread weight of 13 inch tyres oscillates around 2 kg.
For low-profile models with low sidewalls but significant circumference and wide forehead, the proportion of tread weight is greater and can exceed 40% of the weight of the tyre.
Tread is the only component that changes in weight during tyre use. It wears naturally, and the gradual wear of the top layer reduces its weight relatively to its initial weight.