Do not exceed the maximum tire inflation pressures that are molded into the sidewalls of all tires. This inflation pressure is when the tire is cold not when the bike is being ridden or has just been ridden. Air expands with heat generated through use. Even though a lot of instruction sheets neglect to mention the inflation limits are for a cold tire, that is precisely what they mean. Using Metzler as an example, their literature uses suggested tire pressures based on a rider weight of 170 lbs. with no passenger or luggage.For instance the ME 88 Marathon rear tire has a suggested starting pressure of 36-40 lbs. This increases to a suggested pressure of 42-44 lbs. if a passenger is added with no luggage. 45-49 lbs. tire pressure is recommended if the people are heavier than the base guideline of 170 lbs. or luggage is added to the bike.In no case are the pressures to exceed the maximum indicated on the sidewall. Front tires are always a few pounds lighter than the recommendations for the rear as the weight distribution is lighter.These inflation figures are a generalization only. Many things will modify the pressure up or down. For example, high speed riding, rough road conditions or very high temperatures will probably require a moderate increase in pressure. Wanna win that drag race off the line? Well, lowering your tire pressure temporarily will give more traction but beware it will wear the rubber faster


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