Tire code – Wikipedia
The dimensions of a tire, as well as some of its key limitations, are specified by an alphanumeric tire code, which has grown in complexity over the years, with ad-hoc extensions to lettering and numbering schemes.
DOT code
Since February 1, 2021, UK vehicle regulations have prohibited the use of tyres older than 10 years on the front steered axle(s) of heavy goods vehicles, buses, and coaches, and all tyres on these vehicles must display a legible date code.
ETRTO and TRA
National tire standards are influenced by the European Tyre and Rim Technical Organisation (ETRTO) and the Tire and Rim Association (TRA), while the Office of Vehicle Safety Compliance is one of the agencies tasked with enforcing the Federal Motor Vehicle Safety Standard (FMVSS) in the United States.
E-mark
After July 1997, all tires sold for road use in Europe must bear the E-mark, which indicates that the tire has been certified to meet the dimensional, performance, and marking requirements of ECE regulation 30. The number in the circle or rectangle denotes the country code of the government that granted the type approval.
Explanation of tire codes
An optional letter (or letters) indicates the intended use or vehicle class for the tire. If the number is greater than 200, then this is the diameter of the entire tire in millimeters. The letters below indicate the diameter and construction of the tire. If the letter Z indicates a maximum speed over 240 km/h (149 mph), then a metric tire code is used.
Flotation sizes
The Light Truck Numeric or Light Truck High Flotation systems are used by some light-truck tires; if the tire diameter is not specified, section widths ending in zero indicate a 92% aspect ratio; load index and speed rating are not always required for flotation sizes, but must be for any tire approved for street and highway use.
What do numbers on inner tubes mean?
The first number indicates the diameter of your wheel; common tire diameters include 26, 24, 20, 27.5, 29, and 700c; the second number (after the X) indicates the width of your tire; for example, a 26 x 1.75 size indicates a tire diameter of 26 inches and a width of 1.75 inches.
What does 116s mean on a tire?
Light Truck Tire Load Index A light truck tire with a load index of 120/116, for example, has a load capacity of 3,086 pounds for a single tire and 2,756 pounds for two tires.
How do you read a tractor inner tube size?
The first number (16.9) indicates tire width from sidewall to sidewall in inches, while the second number (30) indicates rim diameter in inches.
How do you read a tire code?
The last four digits of this code indicate when your tire was made; the first two numbers indicate what week of the year it was made (out of 52), and the second two numbers represent the year; for example, 5200 indicates that a tire was made in the 52nd week of the year 2000.
Is the inner tube the same size as the tyre?
Inner tubes usually state a wheel diameter and width range for which they will work, such as 26 x 1.95-2.125″, indicating that the tube is intended to fit a 26 inch tyre with a width of between 1.95 and 2.125 inches.
Can I use bigger inner tubes?
Bike inner tubes come in a limited range of sizes, and larger tubes are more likely to get pinched between the tire and the rim. It’s always best to match as closely as possible, but there is some leeway; having a slightly smaller or larger tube will suffice.
What does the R mean in tire size?
P denotes that your tire is a passenger tire; for example, an aspect ratio of 50 indicates that the tire’s section height is 50% of its section width. R denotes the tire’s casing construction; R stands for radial construction.
What’s better load range D or E?
The load range E has a higher maximum load capacity than the load range D for a given brand and size tire, because the E tire is built and rated for 80 psig maximum inflation pressure, whereas the D tire is (as I recall) built and rated for 65 psig maximum inflation pressure.
Can I use 235 tires instead of 225?
Is it possible to interchange 225 and 235 tires? Yes, but only if your car’s rims can accommodate the larger millimeter.
What are inner tubes used for?
The inner tube of a pneumatic tire is an inflatable ring that fits inside the casing of the tire and is inflated with a valve stem. The inflated inner tube provides structural support and suspension, while the outer tire provides grip and protects the more fragile tube.
What do numbers mean on tractor tires?
The three-number system for lawn tractor tires works a little differently: the first number before the “x” indicates the tire’s diameter when inflated and not under load, the middle number between the “x” and the “-,” indicates the tire’s width, and the final number indicates the rim’s width.
Do inner tubes come with valves?
Most inner tubes have a Presta or Schrader valve, which we’ll discuss later; making sure you have the correct valve type for your bike’s wheels is critical.
What does V mean on tires?
V – Speed ratings are represented by letters ranging from A to Z, with each letter corresponding to the maximum speed a tire can sustain under its recommended load capacity, such as V, which equals 149 mph.
What does XL mean on a tire?
XL tyres were developed specifically for use with heavy loads; however, tyre manufacturers’ labeling varies, so you might see XL tyres that are also labeled “reinforced” (RF or RFD), or models labeled EL (Extra Load).
Can I mix V and W rated Tyres?
Fitting new tyres with a lower speed rating than the manufacturer’s original fit can invalidate your car insurance; mixing tyre speed ratings is not recommended.