Originally posted by: GoatMonkey
You'll have a nice bald patch on the middle of your tires and have to replace them sooner, completely canceling out any MPG advantage you might have gotten. Plus they may have a higher chance of blowing out with increased PSI.
I had a friend who filled his car tires to 60 PSI because that's what he had always used on his bicycle.
What an idiot.
BTW-Here is some information on tire inflation.
NEVER INFLATE TO MAXIMUM TIRE PRESSURE!
There is a common misunderstanding that a tire's pressure is stamped on the sidewall. In actuality, this pressure stamped on a tire's sidewall is the MAXIMUM COLD PRESSURE that the tire will safely hold.
Many tires are rated for a maximum cold pressure of 44 psi, to allow the tires to be used on a wide variety of vehicles. Some vehicles may only require 30 psi cold pressure, others may require 38 psi cold pressure. In both cases, this cold pressure is less than the tire's MAXIMUM cold pressure, so the tire can safely be installed on these vehicles.
Tires should be inflated according to the manufacturer's cold specifications, not the maximum pressure stamped on the sidewall of the tire.
Over-inflated tires, even those inflated to maximum pressure, will cause problems with ride comfort, stability and handling, uneven wear, and potential tire failure.
Under-inflated tires will also cause these same problems, but under-inflated tires have greater potential for tire failure.
When in doubt about your tires, stop by your local reputable tire dealer and inquire at the desk. They will be happy to check your tires and tire pressure.
NEVER inflate a tire beyond its maximum rating!
NEVER drive a tire that is severely over- or under-inflated, or it may fail and blow out!
ALWAYS have your tires installed by a trained and certified tire professional.