Tire Width, Tire To Rim, Rim Diameter – This is written like 4. So this wheel is 4. Notice that the size of this tire never specifies the diameter of the entire tire. The first, 4. The second, 3. So a 4.So your tire size means that the outside to outside widest width of your tire is 4. It has often been said that to have good cycling wheel performance, there is a rule that the external rim width of a wheel should be at least 105% of the width of the tyre, or that there is a simple relationship/formula that will predict the aerodynamic performance of a wheel based on rim width vs tyre width.The 105% rule says that the external rim width of your wheel should be at least 105% of your tire’s actual measured width. This ratio allows the airflow to remain attached as it moves from the tire onto the rim, reducing drag and making your bike more aerodynamic.
What tyre size is legal?
The overall diameter of a wheel and tyre fitted to a vehicle must not be more than 50 mm (4WDs) or 15 mm (other vehicles) larger than the largest tyre size listed on the tyre placard and not more than 15 mm less than the smallest tyre size listed on the placard on all vehicles. Generally, you don’t want to go with tires that have a diameter that is more than 3% different from the factory tires. It’s also a good idea to consult with a trusted mechanic before switching to larger or smaller tires.For instance, your vehicle has a set size of rims, but you can buy different sizes of tires to fit those rims, as long as the middle of the tires is the correct size. That being said, a vehicle with bigger rims will often be able to fit larger tires than other vehicles.Having different sizes on some four wheel and all wheel drive vehicles can actually do damage to the vehicle. Since tires vary from brand to brand, and even from model to model, damage can even occur with tires of the same size if they have a large enough difference in circumference.Likewise, it is advised you stick within the 1. Incorrect tyre sizing can cause damage to the car. Bigger rims, or wider tyres, will make contact with the wheel arch, causing excess wear and tear, as well as more difficult driving.So a 4. This tyre would therefore have the appearance of a low profile tyre. Tire Width, Tire To Rim, Rim Diameter – This is written like 4. So this wheel is 4. Notice that the size of this tire never specifies the diameter of the entire tire.In our cases, 3. Our total wheel diameter is thus: 3. A wheel = rim + tire, at least in my neck of the woods.
What is the 3% rule for tires?
The 3% rule states that when replacing tires, the new tire’s diameter should not differ from the original by more than 3%. This guideline helps maintain proper vehicle performance, safety system functionality, and speedometer accuracy. Wider tyres tend to wear faster because they have a larger contact patch with the road, leading to more friction and heat generation. This increased friction can cause the tyres to wear out more quickly.People often assume a larger tire/wheel set up will provide better traction and performance for winter driving. But in fact, a narrower tire with a higher profile (but equivalent overall diameters) combined with a smaller-diameter wheel cuts through snow more effectively.The performance of tyres deteriorates the more worn they become. In fact the difference in stopping distance between tyres with 4mm or tread and tyres with the legal minimum of 1. That is why it is recommended that they are changed once tread levels reach 3mm or less.