Riding on tires with too little air pressure is dangerous. The tires will build excessive heat. This can cause a sudden tire failure. Under inflation may also:
Never inflate a tire unless it is secured to the motorcycle or a tire-mounting machine. Inflating an unsecured tire is dangerous. If it bursts, it could be hurled into the air with explosive force.
Always check the size markings on the tube to ensure that the tire size appears on the tube. Do not fit tubes in radial motorcycle tires, nor fit radials on rims requiring tubes, unless the tubes bear matching size and radial (R) markings.
Keep in mind that hard cornering, passengers, heavy loads, and sustained high speeds will require higher pressures (up to that indicated on the sidewall).
Check your air pressure when the tires are "cold." The tires are "cold" when your motorcycle has been ridden less than a mile at moderate speed or after being stopped for three or more hours. Never release air from a hot tire in order to reach the recommended cold tire pressure. Normal riding causes tires to run hotter and inflation pressure to increase. If you release air when your tires are hot, you may dangerously under inflate your tires.
If your tires lose more than two pounds per square inch (2 psi) per month, the tire, the valve, or wheel may be damaged. Consult your local dealer for an inspection.
Use valve caps to keep valve cores clean and clear of debris and to help guard against air leakage
Never exceed the maximum load rating stamped on the tire sidewall of your tire or the maximum vehicle load rating, whichever is less. Before a trip, determine the total weight of luggage, equipment, and rider(s) to be added to your vehicle.
Never exceed the accessory restrictions and motorcycle load capacity found in the owner's manual, or the maximum load molded on the sidewall of the tire.
Inspect your tires for cuts, cracks, or splits in the tread and sidewall areas. Bumps or bulges may indicate a separation within the tire body. Have your tire inspected by a qualified tire service person. It may be necessary to have it removed from the wheel for a complete inspection.
Inspect your tires for uneven wear. Wear on one side of the tread or flat spots in the tread may indicate a problem with the tire or vehicle. Consult your local dealer.
Inspect your rims also. If you have a bent or cracked rim, it must be replaced.
Storage surfaces should be clean and free of grease, gasoline, or other substances, which can deteriorate the rubber. Improper storage can damage your tires in ways that may not be visible.
Motorcycle Street Tire Size Conversion Chart | ||
Front Tires | ||
Metric | Alpha | Inch |
80/90 | MH | 2.50/2.75 |
90/90 | MJ90 | 2.75/3.00 |
100/90 | MM90 | 3.25/3.50 |
110/90 | MN90 | 3.75/4.00 |
120/80 | N/A | 4.25/4.50 |
120/90 | MR90 | 4.25/4.50 |
130/90 | MT90 | 5.00/5.10 |
Rear Tires | ||
Metric | Alpha | Inch |
110/90 | MP85 | 4.50/4.75 |
120/90 | MR90 | 4.50/4.75 |
130/80 | N/A | 5.00/5.10 |
130/90 | MT90 | 5.00/5.10 |
140/80 | N/A | 5.50/6.00 |
140/90 | MU90 | 5.50/6.00 |
150/80 | MV85 | 6.00/6.25 |
150/90 | MV85 | 6.00/6.25 |
N/A | ||
Motorcycle Off-Road Tire Size Conversion Chart | ||
Front Tires | ||
Metric | Alpha | Inch |
60/100 | 90/80 | 2.50/2.75 |
70/100 | 90/90 | 2.75/3.00 |
80/100 | 100/80 | 3.00/3.25 |
Rear Tires | ||
Metric | Alpha | Inch |
80/100 | 80/90 | 2.50/3.60 |
90/100 | 110/90 | 3.60/4.10 |
100/100 | 120/80 | 4.00/4.10 |
110/100 | 130/80 | 4.00/4.50 |
120/100 | 140/80 | 5.00/5.10 |
Speed Symbol | Max Speed | Speed Symbol | Max Speed | Speed Symbol | Max Speed |
J | 62 mph | K | 68 mph | L | 75 mph |
M | 81 mph | N | 87 mph | P | 93 mph |
Q | 99 mph | R | 106 mph | S | 112 mph |
T | 118 mph | U | 124 mph | H | 130 mph |
V | 149 mph | W | 168 mph | Y | 186 mph |
L.I. | lbs. | L.I. | lbs. | L.I. | lbs. | ||
33 | 254 | 49 | 408 | 65 | 639 | ||
34 | 260 | 50 | 419 | 66 | 661 | ||
36 | 276 | 52 | 441 | 68 | 694 | ||
37 | 282 | 53 | 454 | 69 | 716 | ||
38 | 291 | 54 | 467 | 70 | 739 | ||
39 | 300 | 55 | 481 | 71 | 761 | ||
40 | 309 | 56 | 494 | 72 | 783 | ||
41 | 320 | 57 | 507 | 73 | 805 | ||
42 | 331 | 58 | 520 | 74 | 827 | ||
43 | 342 | 59 | 536 | 75 | 853 | ||
44 | 353 | 60 | 551 | 76 | 882 | ||
45 | 364 | 61 | 567 | 77 | 908 | ||
46 | 375 | 62 | 584 | 78 | 937 | ||
47 | 386 | 63 | 600 | 79 | 963 | ||
48 | 397 | 64 | 617 | 80 | 992 |