Wheels are not one-size-fits-all. Different tire sizes suit different purposes and preferences. The right tires can greatly improve your driving experience, and make your time on the road safer. So, how exactly can you decide which one is best for your car?
First of all, you can find your car manufacturer’s recommended tire’ size written in one of the following places no matter what car you have:
- The owner’s manual
- The placard inside your driver’s side door
- Inside your glove box door
- Inside your gas tank hatch.
How To Read Your Tire Size
Let’s use the following example for tire specifications:
P: The letter P stands for “P-metric”, which signifies that this is a “passenger car” tire type. If you see “LT” instead, it means that you need “light truck” tires instead.
225: This shows the tire section width in millimetres from one sidewall to the other.
50: This number identifies the aspect ratio of your tire’s section height against its width in percentages. In this case, the tire’s height is 0.5x the width.
R: This letter indicates the construction of the tire. R is for radial construction, B is for belted bias. and D is for diagonal bias construction.
17: The next number is the rim diameter in inches.
91: The last number indicates the load index, which is a number that corresponds to a specific number of kilograms or load each tire can support when fully inflated.
S: The last letter corresponds to the speed index, which are different letters corresponding to the different maximum speeds each tire can withstand. For example, “S” is rated for up to 180km/h.
How To Calculate Tire Size In MM
Calculating the diameter of your tire in millimetres can be done in 3 easy steps:
- Section Height = Width x Aspect Ratio
- Combined Section Height = Section Height x 2
- Combined Diameter = Combined Section Height + Rim Diameter (in mm)
Choosing Your Tire Size
In general, there are two rules of thumb to always follow when selecting a tire size.
- The speed index rating, size, and load index should follow your car manufacturer’s recommendation. Avoid choosing a tire that has a lower load index and smaller size than your original tire specification.
- If you are to change your tire size, only increase or decrease the diameter by 2% from the default size. Tires with a diameter that is too small can result in inadequate ground clearance, while too large a diameter could cause the tire to press against the inner side of the wheel arch, and compromise performance.
Point S: Your One-Stop Shop for All Your Tire Needs
If you are considering replacing your tires or changing the size of your tires, Point S Singapore has you covered.
The Point S workshop will be in full operation from June 2nd and will be hosting a number of tire promotions.
These include free tyre condition checks and a special promotional price for their in-house tyre brand, Summerstar, which is designed in Germany and produced solely in Europe by a reputable tyre manufacturer.
If you are new to tires, rest assured that you will be in good hands, as the knowledgeable Point S team will guide you every step of the way to make sure that you make the best decision for you and your car!