Very. Tire pressure is one of the most important maintenance tasks you should perform before every ride. Although the carcass and overall structure of the tire has a significant effect on the overall performance of the tire, for it to function properly you must have sufficient air pressure in the tire.
We recommend that you check your air pressure before every ride, especially when carrying a load. Every 4 psi of air lost in the tire translates to approximately 60 to 70 pounds reduction in load carrying capacity. For example, if your tire pressure is 34 psi, instead of a recommended 41 psi, you would need to take 120 to 140 pounds of load off of the motorcycle. Never exceed the maximum load capacity that is stamped on the sidewall of the tire at the recommended air pressure.
Another reason proper air pressure is so important, is to ensure proper handling of the motorcycle. Never over-inflate a tire, as over-inflation of a tire may reduce the contact patch. Likewise, under-inflation generates uneven contact pressure and support. Both conditions negatively affect the handling and stability of the motorcycle.
We recommend that you only use a mild soap solution to clean your sidewalls and whitewalls. Then rinse with plain water.
Shinko recommends a run-in distance of approximately 100 miles. Before then, maximum power or hard cornering should not be applied to the tires. Proper run-in allows you to familiarize yourself with the feel of the new tires or tire combination, as well as allowing the tire mold release agent applied during the manufacturing process to be worn off.
We recommend that you first consult the owner's manual for your motorcycle to find the original size of the front and rear tires. Once you know the sizes, it is imperative that you only purchase tires of the same size recommended in the owner's manual.
Shinko does not recommend repairing damaged street tires. Temporary repair should not be attempted because secondary damage may occur that results in sudden tire failure or an accident. Shinko also does not recommend the use of liquid sealants, as they are a form of temporary repair that may adversely affect ply material and disguise secondary damage. Never perform an exterior repair and never use an inner tube as a way to repair a street tire. The same recommendations apply to dirt tires, except where no external damage is apparent, and a new inner tube typically repairs a deflated tire.
Wider tires should only be installed with the approval of the motorcycle or tire manufacturer. If wider tires are approved for a particular motorcycle, one size designation it is the typical permissible size increase. Be sure to consider clearance for width and diameter, the effect on stability and handling, and whether your rim is wide enough. Always allow for some tire growth, as all tires will increase in size after they have been inflated and ridden on for a few hundred miles.