Questions on Tyres ? 1. What does this mean 205/55R16W ? 2. What is the average km life span of a tyre ?

Question

3. How often the tyres be rotated ?

Answer 1

Both of the above answers are almost correct.

The number refers to the size of the tire. If it starts with the letter P (P205/55R16 89W) then it uses the P-Metric (Passenger Metric) sizing system. If there is no P at the beginning (205/55R16 91W) then it uses the Euro-Metric size system. In terms of dimensions the two systems are interchangable. The difference is the two systems will, on the same size tire, have different load carry capacity at the same pressure. For example, the P205/55R16 89W when inflated to 35 psi can carry a load of 1,257 pounds. The 205/55R16 91W when inflated to 35 psi can carry 1,312.

The first number = 205 is the "section width" or the width of the tire in milimeters at its widest point (not at the bead or the tread). This point will usually be about halfway down the sidewall. So the section width of this tire is 205 mm. Do not confuse this with the tread width (width of the tread of the tire from inner to outer edge). That number is not expressed in the size and can actually vary quite a bit among different tires of the same size depending on how they are constructed.

The "55" is the "section height" or the height of the tire as measured from the bead to the tread. It is represented as a percentage of the "section width" so that this tires section height is 55% as tall as its section width.

The "R" means radial construction

The "16" is the wheel diameter the tire fits on in inches, so it must be mounted on a 16-inch diameter rim.

The next part of the size description, which you left out of your question, is the "service rating". For this size tire that could be either 89, 90, 91, 94 or 97. Those last two are rare and the size will usually be expressed as something like this; 205/55R16XL 94W (XL + Extra Load). This number often gets overlooked when people are looking at tire sizes but it is in fact crucial as it expressing the load or weight carrying capacity of the tire. If you were to put a P205/55R16 89W tire on a vehicle that specifies a 205/55R16XL 97W tire at 35psi you would be under-rating the load carrying capacity of the tires by more than 500 pounds/227kg. At a more likely pressure of 41 psi the difference becomes 1,232 pounds/560kg!

The last bit, the "W" is the "Speed Rating" of the tire, or an expression of its maximum speed capability. A "W" means a maximum speed capability of 168mph/270kmh. Not to confuse things even more but sometimes the size of a tire with this high a speed capability might also be expressed as "205/55ZR16 91W" with the added "Z" being another way of expressing that the tire has a speed capacity exceeding 149mph/240kmh.

In terms of lifespan, that is a bit harder to guage. A "W" speed rated tire will almost never have a mileage warranty from the manufacturer as the tires are designed for maximum performance capability (grip). They give up tread life to do that. Go down to a lower speed rating like V or H and you will find many tires now that are warranted to get a certain number of miles/km out of them - 50,000 miles/80,000 kilometers for example. But use of tires with these lower speed ratings on a vehicle designed for W rated tires can reduce the vehicles performance.

Tire life is highly dependent on frequency of rotation which is usually recommended every 6,000 miles/10,000km give or take.

Hope that wasn't too much information, but I guarantee it is accurate.

Answer 2

205 refers to width at the bead (205mms)
55 refers to side wall height (55% of bead width)
R stands for radial
16 is the rim size in inches
W is the speed rating (210 kilometers per hour)

Average tyre life 40 to 50,000 kilometers

You should rotate every 3 months.

Answer 3

205 = approximate width in MM
55 = % sidewall height of the 205
R = top speed
16 = tire size in inches (wheel size)
Soft tires (high performance) last between 20,000 - 60,000 miles.
Harder tires (snow tires, touring tires) last between 30,000 - 80,000 miles.
Tires should be rotated every 5,000 miles or at twice a year.