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By mts on
Motorcycle tires have size codes, a set of numbers and letters, which represent different factors like width, aspect ratio, speed rating, rim size, construction, type of the tire, load and speed indices, type of tube and the like. These sets of numbers and letters may either be measured in Metric, Alpha, or using the rare Standard Inch. These are called measurement systems, and they help you know the size of your tire. There are three major systems and each has a different format, which is why it is important to have the motorcycle tire size meaning explained, so you can learn – in order to buy the right tire for your bike.
This system measures the size in millimeters. It is the most commonly used system for motorcycle tires, which is a set of three numbers and letters implying the width of the tire, the aspect ratio of the tire (ratio of tire‘s height to the width) and lastly the rim size given in inches. Immediately after the speed rating, you will find a letter or two letters used to signify the speed rating and the radial construction of the tire consecutively.
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Let us look at an example of this rating from a Shinko motorcycle tire 190/50 ZR 17:
However, the speed rating and the construction of the tire may not be indicated. In this case you will have a set of number in this manner: 100/90 – 19. This Shinko tire reading means it is 100 mm wide, with a 90% aspect ratio and can be mounted on to a rim of 19 inches.
In short, Metric measurement takes either the Width/aspect ratio-rim size format or Width/aspect ratio-speed rating-Tire Construction-Rim size format.
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This is the standard system used in the United States. The measurements are given in inches and the measurements are straight forward.
Let us look at this format used by Shinko on one of their touring tires; MT90 – 16.
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There are 3 key differences between the Metric reading and the Alpha reading:
The wheel construction is denoted by letter “B” otherwise it is assumed to be bias-ply.
This is an outdated system and is only found in classic motorcycle. It is usually given in inches, hence the name Standard Inch measurement system. The aspect ratio of these tires is 100%; and it may or may not be indicated. Another thing to note is that these tires are not belted and are of bias-ply construction.
An example is 3.25H-19
The aspect ratio, though not indicated, is 100% meaning the height of the tire is 100% the width of the tire
Low Profile Inch System
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This is almost similar to the standard system; the difference is that the aspect ratio is 82% instead of 100%. However, on some tires the aspect ratio may be specified as 85%. This system is no longer in use.
Next time you are out shopping for new tires, make sure you have the right size now that you have the readings explained to you.
If you are looking for some motorcycle parts for Harley Davidson, we recommend checking Viking Bags online store.
For All Motorbike Tires
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Choosing Motorcycle Tire Sizes
There are several things to consider when selecting the correct motorcycle tires. Size, dimensions, and other factors will affect the performance and safety of your bike. While there are a lot of aspects to making the best choice, it doesn’t have to be difficult. Here, we’ll guide you through each step in determining motorcycle tire sizes, explained so that you can go ahead and hit the open road!
There are five main aspects to determining the ideal motorcycle tire sizing: width, aspect ratio, speed rating, tire construction and rim diameter. Let’s take a look at each:
The first number or second letter in a tire size represents the nominal width.
Width is measured in a straight line from the furthest point on one sidewall, across the tread, to the furthest point on the opposite sidewall. If there is any question whether or not a larger than OEM tire will fit your bike, youre encouraged to call Tech Service. The different size numbering systems specify widths in different measurements. You can view a width cross reference table below .
You use the aspect ratio to indicate a tire’s cross-sectional profile. A smaller number means a lower profile, and the height-to-width ratio is shown as a percent. For example, if the aspect ratio is 90, that means that your tire’s cross-sectional height is 90% of its width. If the tire has the metric, alpha or low-profile inch numbering system, the aspect ratio will appear immediately after the width.
A speed rating provides the maximum speed at which a tire can be used based on maximum load and inflation pressure. To find the maximum load and inflation pressure, you’ll need to check the sidewall of the tire.
A speed rating also has a letter code, and that is immediately after the width and aspect ratio. It’s part of the three-digit load/speed index. This is on the tire, immediately after the complete size designation. A Z-rated tire has no maximum speed — this rating is for more than 149mph. Check out this table to see what letters correspond with what speed ratings:
| Speed Ratings | ||
|---|---|---|
| Code Letter | Max. MPH | Max. KPH |
| J | 62 | 100 |
| K | 68 | 110 |
| L | 75 | 120 |
| M | 81 | 130 |
| N | 87 | 140 |
| P | 93 | 150 |
| Q | 99 | 160 |
| R | 106 | 170 |
| S | 112 | 180 |
| T | 118 | 190 |
| U | 124 | 200 |
| H | 130 | 210 |
| V220 | 137 | 220 |
| V230 | 143 | 230 |
| V or V240 | 149 | 240 |
| V250 | 155 | 250 |
| V260 | 161 | 260 |
| W or V270 | 168 | 270 |
| V280 | 174 | 280 |
| V290 | 180 | 290 |
| Y or V300 | 186 | 300 |
| Z | above 149 | above 240 |
*Since Z-rated tires have no recognized speed ceiling, the rating simply means higher than 149mph. | ||
After the speed rating is the tire construction, which has two options: Belted (B) or Radial (R). “Belted” means fiberglass, Kevlar or aramid fiber belts, which has added strength and load capacity. But, if a tire does not have (R), then it is bias-ply, which means that it has multiple, overlapping rubber plies. These overlapping plies form a thick layer that is sensitive to overheating and is less flexible.
Rim diameter is the diameter of the rim/wheel on which the tire will be mounted, in inches.
WW: White wall tire
TT: Tube-type tire (requires inner air tube)
TL: Tubeless tire
M/C: Motorcycle tire (in other words, for motorcycles only)
Let’s check out some examples of how to read motorcycle tire dimensions:
Metric tires are most commonly used and can work for sport bikes, cruisers, touring bikes and others.
If there is no speed rating, the “M” will precede the metric size. After the speed rating, there will be a “B” or “R” to indicate if it is belted or radial tire construction
The Alpha size designation is most often used for touring motorcycle tires. Even if a tire doesn’t have a“B” designation after the speed rating, it could be belted.
Often, older motorcycle tires have a Standard Inch System. These tires do not have an aspect ratio designation marking.
The cross-section tire height is 100% of the width. An inch-sized tire is bias-ply construction and is not belted. However, these are being phased out and are not used on newer motorcycles.
Series Size System when the aspect ratio is unspecified, so it will always be 82% unless it is specifically noted to have an 85% aspect ratio. However, manufacturers are no longer using tires with this size system, so you
Because motorcycle tires are manufactured worldwide, there are variations in size designations. Therefore, the chart below does not display exact interchangeability, but it can give you an idea of how to compare widths and replacement sizes. This table should not be used for tires with aspect ratios lower than 80%.
| Permissible Rim Widths | Metric | Alpha | Standard Inch | Low Profile Inch |
|---|---|---|---|---|
| 1.60, 1.85 | 70 | MG | 2.75 | - |
| 1.60, 1.85 | 80 | MH | 3.00 | 3.60 |
| 1.85, 2.15 | 90 | MJ | 3.25 | 3.60 |
| 1.85, 2.15 | 90 | ML | 3.50 | 4.10 |
| 2.15, 2.50 | 100 | MM | 3.75 | 4.10 |
| 2.15, 2.50, 2.75 | 110 | MN | 4.00 | 4.60 |
| 2.15, 2.50, 2.75 | 110 | MP | 4.25 | 4.25/85 |
| 2.15, 2.50, 2.75 | 120 | MR | 4. 50 | 4.25/85 |
| 2.15, 2.50, 2.75 | 120 | MS | 4.75 | 5.10 |
| 2.50, 2.75, 3.00 | 130 | MT | 5.00 | 5.10 |
| 2.75, 3.00, 3.50 | 140 | MU | 5.50 | - |
| 3.50, 4.00 | 150 | MV | 6.00 | - |
| 4.00, 4.50 | 160 | - | 6.25 | - |
Find tires for your ATV or Motorcycle
Now that you have a better idea of all the size considerations, it’s time to get your motorcycle or ATV tires!
Find Motorcycle Tires Find ATV/UTV Tires
Introduction
How to decipher the marking of motorcycle tires
Correspondence table for metric and inch tire marking systems
Conclusion
Motorcycle tires are impossible to choose correctly if you do not understand their sizes.
Otherwise, at best, you risk bringing just a useless piece of rubber from the store. To determine the sizes, we have prepared a short decoding method and a comparison table of tire dimensions. nine0006
Any motor rubber has a sea of information on the sidewall about the properties, purpose and, of course, size. We need to figure it out, and then compare the readings with the table. You can learn more about motorcycle tire labeling in our previous article.
As a rule, the main marking on the side of the tire looks like this: 120/80 R16 59S. This is the so-called metric marking. Let's understand it in more detail:
120 - profile width from edge to edge of the tread, expressed in millimeters. nine0006
80 - profile height, expressed as a percentage.
R - radial type of construction.
16 - diameter of the landing area. This indicator should correspond to the same diameter of the rim on which the tire will be put on.
59 - load index, or the maximum weight that the tire can withstand without loss of performance. We are looking for it in the table:
| Tire load index | |||||||
| 40 | 140 | 53 | 206 | 66 | 300 | 79 nine0059 | 437 |
| 41 | 145 | 54 | 212 | 67 | 307 | 80 | 450 | nine0060
| 42 | 150 | 55 | 218 | 68 | 315 | 81 | 462 |
| 43 | nine0062 56 | 224 | 69 | 325 | 82 | 475 | |
| 44 | 160 | nine0005 57 | 230 | 70 | 335 | 83 | 487 |
| 45 | 165 | 58 | 236 | 71 | 345 | 84 | 500 |
| 46 | 170 | 59 | 243 | 72 nine0059 | 355 | 85 | 515 |
| 47 | 175 | 60 | 250 | 73 | 365 | nine0062 530 | |
| 48 | 180 | 61 | 257 | 74 | 375 | 87 | nine0005 545 |
| 49 | 185 | 62 | 265 | 75 | 387 | 88 | 560 |
| nine0005 50 | 190 | 63 | 272 | 76 | 400 | 89 | 580 |
| 51 | nineteen5 | 64 | 280 | 77 | 412 | 90 | 600 |
| 52 | 200 | 65 nine0059 | 290 | 78 | 425 | 91 | 615 |
S is an index of the speed at which the bike can move without losing ride stability, grip and other useful tire characteristics.
The value is also in a special table:
The models in the top are arranged in terms of price / quality ratio. In the process of writing it, we were guided by the reviews of amateur bikers, professional tests, and were also guided by our own subjective opinion and many years of experience with tires. nine0006
| Speed index | Maximum speed, km/h |
|---|---|
| A | 40 |
| B | 50 |
| C | 60 |
| nine0059 | 65 |
| E | 70 |
| F | 80 |
| G | 90 |
| J | 100 |
| nine0005 K | 110 |
| L | 120 |
| M | 130 |
| N | 140 |
| P | 150 |
| Q | 160 |
| R | 170 |
| S | 180 |
| T | 190 |
| U | 200 nine0059 |
| H | 210 |
| V | 240 |
| W | 270 |
| Y | 300 |
| VR | nine0005 >210 |
| ZR | >240 |
| (W) | >270 |
| Z | >300 |
This method of marking tires is followed by most manufacturers, but there are those who prefer alternative types, where the dimensions are indicated in inches.
For example, this one is 3.25H-19. Everything is simple here: 3.25 is the tire width expressed in inches, H is the speed index, 19 is the bore diameter.
Sometimes an inch designation can be used instead of the usual millimeter, for example, like this: 4.60/80 R16.
There is a rather rare alpha system created mainly for sports tourists. For example, this type of MM90S-16, where: MM - profile width in inches (3.75), 90 - profile height in percent; S - speed index, 16 - diameter of the landing rim of the tire.
| Marking alpha | Width in inches |
|---|---|
| MG | 2.75 |
| MH | 3.00 |
| MJ | 3.25 |
| ML nine0059 | 3.50 |
| MM | 3.75 |
| MN | 4. |
| MP | 4.25 |
| MR | 4.50 |
| MS | 4.75 |
| MT | 5.00 |
| MU | 5.50 |
| MV | 6.00 |
To make it easier for you to determine what the inch size corresponds to in the metric system and vice versa, we have prepared a comparison table for you. nine0006
| Tire size in. | Load index | Permissible rim width, inch. | Tire size | ||||
| Alpha | Metric | ||||||
| Standard | nine0062 100 | 90 | 80 | ||||
| 2. | 40 | 46 | 1.50-1.85 | MH 90-16 nine0059 | 80/100-16 | 80/90-16 | 90/80-16 |
| 3.00-16 | 40 | 48 | 1.60-2.15 | MH 90-16 | nine0/100-16 | 90/90-16 | 100/80-16 |
| 3.25-16 | 48 | 55 | 1.85-2.50 | MJ 90-16 | 100/100-16 | 100/90-16 | 110/80-16 |
| 3.50-16 | 52 | 58 | 1.85-2.50 | ML 90-16 | 100/100-16 | 100/90-16 | 110/80-16 |
| 4.60-16 | 58 | 59 | 1. | MM 90-16 | 100/100-16 | 110/90-16 | nine0062 |
| 2.75-17 | 41 | 47 | nine0005 1.50-1.85 | MH 90-17 | 80/100-17 | 80/90-17 | 90/80-17 |
| 3.00-17 | 41 | 50 | 1.60-2.15 nine0059 | MH 90-17 | 90/100-17 | 90/90-17 | 100/80-17 |
| 4.50-17 | 50 | 67 | 2.15-3.00 | MR 90-17 | 110/100-17 | 130/90-17 | 140/80-17 |
| 4.60-17 | 50 | 62 | 1. | MS 90-17 | nine0062 110/90-17 | 120/80-17 | |
| 5.10-17 | 50 | 67 | 2.50-3.50 | MT 90-17 | 110/100-17 | 130/90-17 | 140/80-17 |
| 2.75-18 | 42 nine0059 | 48 | 1.50-1.85 | MH 90-18 | 80/100-18 | 80/90-18 | 90/80-18 |
| 3.00-18 | 47 | 52 | 1.60-2.15 | MH 90-18 | 90/100-18 | 90/90-18 | 100/80-18 |
| 3.25-18 | 52 | 59 | nine0005 1. 85-2.50 | MJ 90-18 | 100/100-18 | 100/90-18 | 110/80-18 |
| 3.50-18 | 56 | 62 | 1.85-2.50 nine0059 | ML 90-18 | 100/100-18 | 100/90-18 | 110/80-18 |
| 3.60-18 | 51 | 62 | 1.85-2.50 | nine0005 MH 90-18 | 100/100-18 | 90/90-18 | 100/80-18 |
| 4.00-18 | 64 | 69 | 2.15-3.00 | MN 90-18 nine0059 | 110/100-18 | 120/90-18 | 130/80-18 |
| 4.10-18 | 60 | 69 | 1.85-3.00 | ML 90-18 | nine0005 100/100-18 | 100/90-18 | 110/80-18 |
| 4. | 64 | 69 | 1.85-3.00 | MM 90-18 | 110/100-18 | 110/90-18 | 120/80-18 |
| 4.25-18 | 66 | 69 | 2.15-3.00 | ML 90-18 | 110/100-18 | nine0062 130/80-18 | |
| 4.60-18 | 63 | 69 | 1.85-3.00 | MR 90-18 | 110/100-18 | 120/90-18 | 130/80-18 |
| 3.00-19 | 49 | 54 nine0059 | 1.60-2.15 | MH 90-19 | 90/100-19 | 90/90-19 | 100/80-19 |
| 3. | 54 | 54 | 1.85-2.50 | MJ 90-19 | 100/100-19 | 100/90-19 | 110/80-19 |
| 3.50-19 | 54 | 57 | 1.85-2.50 | nine0062 100/100-19 | 100/90-19 | 110/80-19 | |
| 3.60-19 | 52 | 54 | 1.85-2.50 | MH 90-19 | 100/100-19 | 90/90-19 | 100/80-19 |
| 2.75-21 | 45 | 54 | 1.50-1.85 | MH 90-21 | 80/100-21 | 80/90-21 | 90/80-21 |
| 3. | nine0005 51 | 57 | 1.60-2.15 | MH 90-21 | 90/100-21 | 90/90-21 | 100/80-21 |
Keep this chart for yourself and you will always have data on how to determine the size of motorcycle tires. In the BlackTyres online store, the selection of new clothes will be much faster and easier, because you can choose tires according to the model and size of the wheels of your bike. Just sort them using filters and choose your favorite tires. nine0002
| Tire size in inches | Tire size metric | ||
| 100 | 90 | 80 | |
2. 75 | 80/100 | 80/90 | nine0062 90/80|
| 3.00 | 90/100 | 90/90 | 100/80 |
| 3.25 | 100/100 | 100/90 | 110/80 |
| 3.50 | 100/100 | 100/90 | 110/80 |
| 3.60 | 100/100 | 100/90 | 100/80 |
| 4.00 | 110/100 | 100/90 | 110/80 |
| 4.10 | 100/100 | 110/90 | 120/80 |
| 4.25/85 | 110/100 | 120/90 | 130/80 | nine0060
| 4.50 | 110/100 | 110/90 | 120/80 |
4. 60 | 100/100 | 120/90 | 130/80 |
| 5.10 | 110/100 | 130/90 | 140/80 |
Explanation of rubber marking abbreviations:
120/70 Z 12 m/c (58W)
| Maximum speed | |||||||
| MPH | km/h | ||||||
| V | 149 | 240 | |||||
| (V) | over 149 | over 240 | |||||
| W | 168 | 270 | |||||
| (W) | over 168 | over 270 | |||||
| Z | over 149 | over 240 | |||||
| Y | 186 | 300 | |||||
| Tire load index | |||||||
| 40 | 140 | 53 | 206 | 66 | 300 | 79 | 437 |
| 41 | 145 | 54 | 212 | 67 | 307 | 80 | 450 |
| 42 | 150 | 55 | 218 | 68 | 315 | 81 | 462 |
| 43 | 155 | 56 | 224 | 69 | 325 | 82 | 475 |
| 44 | 160 | 57 | 230 | 70 | nine0062 33583 | 487 | |
| 45 | 165 | 58 | 236 | 71 | 345 | 84 | 500 |
| 46 | 170 | 59 | 243 | 72 | 355 | 85 | 515 |
| 47 | 175 | 60 | 250 | 73 | 365 | 86 | 530 |
| 48 | 180 | 61 | 257 | 74 | 375 | 87 | 545 |
| 49 | 185 | 62 | 265 | 75 | 387 | nine0062 88560 | |
| 50 | 190 | 63 | 272 | 76 | 400 | 89 | 580 |
| 51 | 195 | 64 | 280 | 77 | 412 | 90 | 600 |
| 52 | 200 | 65 | 290 | 78 | 425 | 91 | 615 |
| Dimension conversion | |||||
| Bar | psi | Bar | psi | Bar | psi |
1. 2 | 17 | 1.9 | 28 | nine0062 2.638 | |
| 1.3 | 19 | 2.0 | 29 | 2.7 | 39 |
| 1.4 | 20 | 2.1 | 31 | 2.8 | 40 |
| 1.5 | 22 | 2.2 | 32 | 2.9 | 42 |
| 1.6 | 23 | 2.3 | 34 | 3.0 | 44 |
1. 7 | 25 | 2.4 | 35 | 3.1 | 45 |
| 1.8 | 26 | 2.5 | 36 | 3.2 | 46 |
| Rim section height. Motorcycle tire width. Rim width. Disc width | |||
| Rim width, inches | Tire width, mm | ||
| 6.50 | 200 | ||
| 6.25 | 200 | nine0060 | |
| 6.00 | 180 | 190 | 200 |
5. 5 | 180 | 190 | |
| Tire profile height 60, 65 and 70% | ||||
| Rim width, inches | Bar width mm | |||
| 6.50 | 230 | |||
| 6.25 | 200 | 230 | ||
| 6.00 | 200 | 230 | ||
| 5.50 | 170 | 180 | 200 | |
| 5.00 | 160 | 170 | 180 | |
4. 50 | 140 | 150 | 160 | 170 |
| 4.25 | 140 | 150 | 160 | 170 |
| 4.00 | 130 | 140 | 150 | |
| 3.75 | 120 | 130 | 140 | |
| 3.20 | 120 | 130 | ||
| 3.00 | 110 | |||
00 
75-16 
85-3.00 
85-3.00 
25/85-18 
25-19 
00-21 
