Conversion to miles per hour means an L-rated tire has a maximum speed of 75 mph and a Y-rated tire can be run up to 186 mph. The tire with the 101H index is "H" speed rated to a maximum of 130 mph. The 102T tire has the lower "T" speed rating of 118 mph.
Prior to 1991, tire speed ratings were shown inside the tire size, before the "R" construction type. The available codes were SR (180 km/h, 112 mph), HR (210 km/h, 130 mph), VR (in excess of 210 km/h, 130 mph). Tires with a speed rating higher than 300 km/h (186 mph) are indicated by a Y in parentheses.
Scott Slemmons, senior sales representative, Maxxis: A touring tire is a premium tire designed to provide longer tread life, combined with a smooth quiet ride. Most touring tires are all-season rated, which provides improved wet and dry road traction.
Despite the low installation fee at Walmart — $12 per tire — the package lands in third place. The deal is less generous than that offered by its two top rivals. It includes mounting, valve stems, and lifetime balance and rotation after every 7,500 miles, plus a lug re-torque after the first 50 miles.
Treadwear. The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test track. In theory, this means that a tire with a 200 grade will wear twice as long as a tire with a 100 grade.
Your tyre's load index relates to its maximum carrying capacity (in kg). You'll find the load rating of your tyre on the sidewall, just to the right of the diameter. For example, a tyre with a load index of 91 can carry 615kg of weight.
As of 1997, the traction grades from highest to lowest are “AA”,”A”,”B” and “C”. A tire graded “AA” may have relatively better traction performance than a tire graded lower, based on straight-ahead braking tests. The grades do not take into consideration the cornering or turning performance of a tire.
For tires having a maximum speed capability above 240 km/h (149 mph), a “ZR” may appear in the size designation. For tires having a maximum speed capability above 300 km/h (186 mph), a “ZR” must appear in the size designation. Consult the tire manufacturer for maximum speed when there is no service description.
"UTQG" stands for "Uniform Tire Quality Grading". A system developed by the Department of Transportation, which helps consumers compare and rate tires on tread wear, traction, and temperature. Example: a tire with a UTQG of 400 AB. However, please don't link treadwear grades with your projected tire mileage.
What is the difference between R and ZR tyres ? ZR basically means the tyre is adapted for speeds above 149 mph. ZR tyres includes the speed ratings V(149mph), W(168mph) and Y(186mph). Before 1990, the manufacturers used "ZR" to mean high performance tyres before the ratings got refined with W, Y…
R indicates it is a "radial" tyre construction. Almost all tyres in use today are of radial construction. This means that the plies of tyre cord extend across the casing from bead (also called "heel") to bead. 17: this is the inside diameter of the tyre, in other words the rim height.
Speed Rating V. Once the highest speed rating a tire could have, “V” used to represent a maximum of 149 mph (240 kph) or more. Nowadays, it means 149 mph but no higher.
Example: 215/60R15. 215 is the width of the tyre in millimetres. 60 is the aspect ratio or tyre profile. R means it is radial construction. 15 is the diameter of the wheel rim in inches.
While a Z-speed rating still often appears in the tire size designation of these tires, such as 225/50ZR16 91W, the Z in the size signifies a maximum speed capability in excess of 149 mph, 240 km/h; the W in the service description indicates the tire's 168 mph, 270 km/h maximum speed.
The sidewall height or "aspect ratio" of a 285/75/R16 tire is 75% of 285mm. Example: 285/75R16 (285 X 75 / 2540 x 2) + 16 = 32.8 inches tall. Our tire calculator makes this happen for you.
|Diameter inches (mm)||31.61 (802.8)||32.71 (830.8)|
|Width inches (mm)||10.43 (265)||11.22 (285)|
|Circum. inches (mm)||99.29 (2522.07)||102.76 (2610.04)|
|Sidewall Height inches (mm)||7.3 (185.5)||7.85 (199.5)|
305/55R20 Tires. 305/55R20 tires have a diameter of 33.2", a section width of 12.0", and a wheel diameter of 20". The circumference is 104.3" and the revolutions per mile are 608.
|Diameter inches (mm)||31.91 (810.5)||33.21 (843.5)|
|Width inches (mm)||10.83 (275)||12.01 (305)|
|Circum. inches (mm)||100.25 (2546.26)||104.33 (2649.93)|
|Sidewall Height inches (mm)||5.95 (151.25)||6.6 (167.75)|
While standard SAE tire sizes are easy to understand (a 35x12.50-16 tire runs 35 inches tall by 12.5 inches wide for a 16 inch wheel), many popular tires, particularly those under 35" tall, use harder to visualize metric dimensions (a 315/75R16 tire is 315 mm wide with a sidewall height that is 75% of the width for a