LawSpeed ​​index for tires over 300 km/h? All info!

# Speed ​​index for tires over 300 km/h? All info!

[Update: 01.11.2023] In our article “Explanation! What do the tire names say?“ we have already dealt extensively with all the important numbers and symbols that are printed on the tire sidewall. As a result, we also dealt with the speed index and inserted a table starting with value A1 (up to 5 km/h) up to value Y (up to 300 km/h). But nowadays there are quite a few vehicles that are sold with a registered maximum speed of over 300 (e.g. the Alpine B5). Because the supposedly highest speed index "Y" but only up to 300 kilometers per hour, the question arises: what to look for when buying?

### a little hint makes the difference

There is no "higher" identifier than ZR and Y for car tires. The resolution is that one example on a bracket with a Y or a hint like ZR (Y) / (Y97) must pay attention to at the end of the key data. Anything over 300 km/h will, however discord individually approved by the respective tire manufacturer. The Bugatti Veyron drives over 400 km/h and wears tires with the designations 265/690-ZR-500-A and 365/710-ZR-540-A from Michelin.

Simply blocking it is not a good idea. If you plan to install a different type of tire than the one installed at the factory, you must contact the tire manufacturer and ask whether the desired tire can be used. The speed index Y in brackets only says that the tire can be used for speeds over 300 km/h. But he doesn't say how fast it can go at most. So whether 320, 340 or 400 km/h and it does not say whether the tire is approved for the desired vehicle.

### what are ZR(Y) tires

A tire with the ZR(Y) note fulfills at least the values ​​of a Y tire and may also be approved for speeds over 300. Therefore, the load and speed index are given in brackets. They can also be recognized by the letter Z, which precedes the R (for radial). In any case, the prerequisite for using such a ZR(Y) tire for speeds over 300 km/h is one Manufacturer's certificate or tire approval. And that also applies to motorcycle tires with the speed index ZR(W), which are designed for speeds of more than 270 km/h. are suitable. If you want to drive a different tire than the one that was installed at the factory, you have to ask the tire manufacturer.

### Speed ​​index (Y) also over 300 km/h

If the speed index (Y) is noted on the tire, then you can drive over 300 km/h with these tires. However, a manufacturer's certificate or tire release is required necessary.

In order to be able to issue a release/inflating pressure recommendation, the tire manufacturer needs detailed data from the vehicle. The vehicle registration document is used to transmit this data, and the manufacturer usually has a special contact form on its website. You can find the form via the usual search engines with the term "Hankook tire approval, Toyo tire approval, Falken tire approval" etc. Info: Many manufacturers give save Release over 300 km/h V.-max.

Speed ​​index for winter tires: Winter tires have special requirements and exceptions when it comes to speed ratings. While M+S tires (mud & snow) may be driven with a lower index under certain conditions, the driver must always observe the maximum permissible speed and, if necessary, attach a corresponding sticker to the vehicle.

How to calculate the speed index? If your vehicle requires a higher speed index than its actual maximum speed, there is a special formula that allows you to determine the minimum required index. This can help make the right tire selection and potentially save money.

VR & ZR tires – what are they? Previous generations of high-speed tires bore these designations. If your older vehicle requires such tires, you should contact a tire dealer to find modern alternatives that meet current standards.

Find the speed index in the vehicle registration document: You can find the required tire indices for your vehicle in the registration certificate. This section explains where exactly you can find this information, depending on the type of vehicle registration you have.

### Tire speed index

• Definition: Indicates the maximum permitted speed of a tire.
• Purpose: Guarantee of trouble-free continuous operation with correct tire pressure.
• Risks if exceeded: Overheating, tread may come loose.
• Test procedure: Rolling test bench. Speed ​​increase of 10 km/h every 10 minutes up to the specified maximum.

Where can I find the speed index?

• Tire wall: Last letter, e.g. “205/55 R 16 91 V” – “V” stands for 240 km/h.
• Vehicle papers: Lines 15.1 and 15.2 of the registration certificate part 1.
• CoC document: Numbers “32. Wheel tires” and/or “50. Remarks".

Speed ​​Index Letters Meaning

• Code letters: Indicate the maximum permitted speeds.
• Higher speed index allowed: If higher than in the vehicle registration document, e.g. W tires instead of V tires.
• Lower speed index: Not allowed except in special cases.
• VR & ZR: Old. For older, fast vehicles. No longer standardized.
• Capacity: Decreases at speeds above 210 km/h. Number before the speed index letter defines it.

Winter tire exceptions

• Speed ​​index may be lower: With M+S symbol or Alpine pictogram.
• Driver must be informed: By sticker or display.

Regulation Italy: winter tires in summer

• M+S tires: Only permitted in summer with the correct speed index.
• Exception: Speed ​​index “Q” or below, common for motorhomes.
• winter half-year: Usual rules apply. Lower index winter tires allowed if speed sticker is present.

## Speed ​​index table

speed index allowed
V-Max.
F-Index 80 km/h
G-Index 90 km/h
J-Index 100 km/h
K-Index 110 km/h
L-Index 120 km/h
M-Index 130 km/h
N-Index 140 km/h
P-Index 150 km/h
Q-Index 160 km/h
R-Index 170 km/h
S-Index 180 km/h
T-Index 190 km/h
U-Index 200 km/h
H-Index 210 km/h
V-Index 240 km/h
W-Index 270 km/h
Y-Index 300 km/h
VR-Index > 210 km / h
ZR-Index (older name. Tips on VR/ZR see below) > 240 km / h

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