What is the V number on tires?
Each letter coincides to the maximum speed a tire can sustain under its recommended load capacity. For instance, v is equivalent to a maximum speed of 149 mph. Even though a tire can perform at this speed general tire does not advocate exceeding legal speed limits. For example, a tyre that reads 255/40 r20 101v shows v to be the tyre speed rating. The tyre speed rating chart below shows that v corresponds to 149 mph. Therefore, tyres with this speed rating should not be driven over 149mph.
Is V or H better on tires?
H-rated tires are thoroughly tested to safely handle speeds up to 130 mph, while V-rated tires show reliable performance at sustained speeds up to 149 mph, which is an important distinction for vehicles that travel at higher speeds. It is not recommended to fit new tyres with a lower speed rating to what is recommended for your vehicle. Whilst choosing to equip your car with a higher speed rating is safe, replacing your tyres with those of a lower speed rating will compromise the safety of your vehicle.For example, when you repair a sidewall on an H, V, or Z-rated tire, you should no longer use the tire at extreme speeds. Similarly, if you repair a hole smaller than 1/4-inch in the tread, the original speed rating may no longer apply. If customers plan high-speed activities, replacing the tire is the safest option.
What does the 89h mean on a tire?
The 89 in the example tire number indicates its load index rating. There’s a standard chart that lists all possible load indices and their weights, but 89 corresponds to a load capacity of 1,279 pounds when the tire is maximally inflated. The load index symbol indicates how much weight a tire can support, based on the following standard chart (see below). In our example, the load index is 89. This means the tire has a load capacity of 1,279 pounds, when inflated to the tire’s maximum air pressure rating.
What is the 105% rule on tires?
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. The ideal maximum calculated upsize that can be done without upsetting the car’s dynamics is around three percent of the original total tyre diameter. Any increase above this will result in a noticeable drop in fuel efficiency and compromise ride and handling.The 3% tire rule is a guideline for upsizing tires. It recommends keeping the new tire’s diameter within 3% of the original to avoid affecting performance and safety.