A tyre's width can influence several aspects of a vehicle's handling characteristics.

It is the vehicle's only contact patch with the ground, and it provides both propulsion and braking forces. Because of this, each new tyre design must be carefully studied to ensure that it meets required performance standards throughout its life. In addition, a tyre's dimensions also affect fuel economy and emissions.

The tyre width is defined as the linear distance between the out-edges of its inner surfaces when mounted and inflated on a specified rim. The tyre section width is a major parameter influencing a tyre's rolling resistance. Other parameters such as sidewall height also have an influence, which means that two tires of equal width may have different rolling resistance.

The rim width is the width of the wheel on which a tyre is mounted. It is usually stamped on the wheel as "rim width" in inches or millimetres. The rim internal width affects both the lateral and sidewall stiffness of the tyre-wheel assembly and the maximum tyre sidewall height that can be mounted on the wheel. Tyre manufacturers provide a recommended rim size and width range for different tire sizes.

Always mount tyres consistent with the internal rim width of the wheels of the car or bike.

When a tyre is mounted on a wheel rim narrower than the recommended tire widths, the sidewalls are subject to higher stresses. This can lead to excessive tyre wear and reduced tyre life. In addition, a narrower tyre on a wider rim will have less lateral stiffness than a wider tyre on a narrower rim, which can adversely affect the vehicle's handling.

How much wider should a tyre be than the rim?

Tyres are available in a variety of widths to suit different vehicles and riding styles. While the tire width and rim width may be the same size, there is a recommended gap between the two measurements that will ensure optimal performance. The approved rim width range guidelines require that for every 0.5 inches change in rim width; the tyre width should have a corresponding width change of about 5mm. Generally, it is recommended that the tyre width be about 1-1.5 inches wider than the internal rim width. This will provide stability and prevent the tyre from rubbing against the rim while in use. Wider tyres mounted on wider rim widths also offer more grip and traction, making them ideal for riding in rougher terrain.

What are some factors that influence rolling resistance?

The overall width of a tyre is one of several parameters influencing its rolling resistance. Other factors include the tyre diameter, type, and construction of the tyre, aspect ratio, as well as the inflation pressure and operating temperature. Tyre rolling resistance accounts for a significant portion of a vehicle's energy consumption, so it is important to select tyres with the lowest rolling resistance possible.

When selecting new tyres, it is important to consider all of the factors that influence rolling resistance. The width of the tyre should be just one part of the equation. Other important factors include the type of tyre (summer, winter, all-season), tread width in relation to wheel width, construction (single or dual compound), and inflation pressure.

In general, narrower tyres have lower rolling resistance than wider tyres. This is because a narrower tyre has less contact area with the road, which creates less friction. However, there are many other factors to consider when choosing tyres, so it is important to consult with a tyre specialist to find the best option for your vehicle.

What types of cars need wide tyres?

Sports cars, modified cars, four-wheel-drivese and high-performance vehicles are often required to have wider tyres than other types of cars. This is because their tyres are subject to higher stress levels during daily usage. Wide size tyres enhance the grip and traction on these types of vehicles, improving stability during sharp turns or cornering at high speeds.

In addition to wide wheel size, the rim diameter, thus the overall diameter of tires used in high-speed sports, is shorter to keep the car's centre of gravity as close to the surface as possible.

Wide tyres are also preferred for off-road driving because they offer better traction in various terrain. Some examples include dirt tracks, gravel roads, or muddy trails where larger rocks might be present. Wider tyres provide more surface contact with the road so that each tyre does not need to support as much weight individually. This reduces the risk of losing control when travelling over rough terrain at high speed.

What types of cars require narrow tyres?

Narrow tyres are often preferred for small cars with a low centre of gravity. This helps to enhance their fuel efficiency and overall handling capabilities. They also require less maintenance since the stress placed on a smaller tyre is lower than a larger tyre. When selecting new tyres, it is important to factor in all of the parameters that contribute to the vehicle's best performance, including tire width. Narrow tyres can provide benefits such as improved fuel economy and better handling in certain conditions. However, these may not be ideal for drivers who travel off-road or who need better traction over wet or snowy surfaces.

How much do tyres cost?

The cost of tyres is determined by several factors, including size, construction, tread wear, and type. The average price for a new tyre ranges from $50 to $300 per piece. However, this price may vary depending on the tire maker, brand, and type of tyre (e.g., for general purposes, all weather-terrain tires, or snow tyres for use in winter). A wider tyre with a wider rim size will cost more than a narrower size tyre.

What is the average price of a set of rims?

The average price for a set of rims is $500 to $1,000 per set. However, this price can vary depending on the tyre size, type of rim, and rim profile. The most expensive rims are those made of carbon fibre, which can cost up to $10,000 per set - perfect to show off your Pirelli tyres. Alloy rims are very popular and have a price between $500 and $1,000 per set.

Are alloy rims more expensive than steel ones?

Yes, alloy rims are typically more expensive than steel ones. This is because they require a greater amount of time and labour to produce. They also tend to be lighter in weight with a smoother surface finish compared to most steel alternatives. Some reasons why people opt for alloy rims include their attractive appearance, strength, durability, corrosion resistance properties.

What are rims made from?

Rims are typically made from aluminium or alloy to enhance the car's performance. However, some manufacturers may use steel for certain models of cars. Rims can also be made from carbon fibre, a lightweight and strong material. This makes them ideal for high-performance vehicles that require enhanced speed and agility.

Wide rims with wider tyres may be necessary for cars that are used in extreme conditions, such as off-road driving or racing. Narrow wheels and tires may provide benefits such as improved fuel economy and better handling in certain conditions. However, these may not be ideal for drivers who travel off-road or who need better traction over wet surfaces. The cost of tyres and wheels can vary depending on size, construction, tread wear, type, and tyre manufacturer.

Fixing up a car? You might have to make sure you follow the guidelines for modified vehicles, as outlined here by the NSW Government. Check to see if it applies to your area.