Speed and Construction
As with four-wheeled vehicles, tyres for motorcycle have a tyre code, which describes a tyre's width, height/width aspect ratio, wheel diameter, load index and speed rating. The most common are:
- 3 digit number: The "nominal section width" of the tyre in millimetres; the widest point from both outer edges.
- /: Slash character for character separation.
- 2 or 3 digit number: The "aspect ratio" of the sidewall height to the total width of the tyre, as a percentage.
- An optional letter indicating construction of the fabric carcass of the tyre:
- B: bias belt (where the sidewalls are the same material as the tread, leading to a rigid ride)
- D: diagonal
- R: radial
- if omitted, then it is a cross ply tyre
- 2 digit number: Diameter in inches of the wheel that the tyre is designed to fit.
- 2 or 3 digit number: Load index; see table below
- 1 or 2 digit/letter combo: Speed rating; see table below
Load index
| LI | kg | LI | kg | LI | kg | LI | kg | LI | kg |
|---|---|---|---|---|---|---|---|---|---|
| 19 | 77,5 | 36 | 125,0 | 53 | 206 | 70 | 335,0 | 87 | 545,0 |
| 20 | 80,0 | 37 | 128,0 | 54 | 212,0 | 71 | 345,0 | 88 | 560,0 |
| 21 | 82,5 | 38 | 132,0 | 55 | 218,0 | 72 | 355,0 | 89 | 580,0 |
| 22 | 85,0 | 39 | 136,0 | 56 | 224,0 | 73 | 365,0 | 90 | 600,0 |
| 23 | 87,5 | 40 | 140,0 | 57 | 230,0 | 74 | 375,0 | 91 | 615,0 |
| 24 | 90,0 | 41 | 145,0 | 58 | 236,0 | 75 | 387,0 | 92 | 630,0 |
| 25 | 92,0 | 42 | 150,0 | 59 | 243,0 | 76 | 400,0 | 93 | 650,0 |
| 26 | 95,0 | 43 | 155,0 | 60 | 250,0 | 77 | 412,0 | 94 | 670,0 |
| 27 | 97,5 | 44 | 160,0 | 61 | 257,0 | 78 | 425,0 | 95 | 690,0 |
| 28 | 100,0 | 45 | 165,0 | 62 | 265,0 | 79 | 437,0 | 96 | 710,0 |
| 29 | 103,0 | 46 | 170,0 | 63 | 272,0 | 80 | 450,0 | 97 | 730,0 |
| 30 | 106,0 | 47 | 175,0 | 64 | 280,0 | 81 | 462,0 | 98 | 750,0 |
| 31 | 109,0 | 48 | 180,0 | 65 | 290,0 | 82 | 475,0 | 99 | 775,0 |
| 32 | 112,0 | 49 | 185,0 | 66 | 300,0 | 83 | 487,0 | 100 | 800,0 |
| 33 | 115,0 | 50 | 190,0 | 67 | 307,0 | 84 | 500,0 | - | - |
| 34 | 118,0 | 51 | 195,0 | 68 | 315,0 | 85 | 510 | - | - |
| 35 | 121,0 | 52 | 200,0 | 69 | 325 | 86 | 530,0 | - | - |
Speed rating
| Rating | Speed (km/h) | Speed (mph) |
|---|---|---|
| Moped | 50 | 30 |
| J | 100 | 62 |
| K | 110 | 69 |
| L | 120 | 75 |
| M | 130 | 81 |
| P (or-) | 150 | 95 |
| Q | 160 | 100 |
| R | 170 | 105 |
| S | 180 | 113 |
| T | 190 | 118 |
| U | 200 | 125 |
| H | 210 | 130 |
| V | 240 | 150 |
| W | 270 | 168 |
| Z | over 240 | over 150 |
Read more about this topic: Motorcycle Tyre
Famous quotes containing the words speed and/or construction:
“Life is too short to waste
In critic peep or cynic bark,
Quarrel or reprimand:
‘Twill soon be dark;
Up, heed thine own aim, and
God speed the mark!”
—Ralph Waldo Emerson (1803–1882)
“When the leaders choose to make themselves bidders at an auction of popularity, their talents, in the construction of the state, will be of no service. They will become flatterers instead of legislators; the instruments, not the guides, of the people.”
—Edmund Burke (1729–1797)