Quote:
Originally Posted by pcs0snq
So tire rack or some www sourse is saying you can exceed the side wall list tire pressure when the tire is HOT and subject to the most issues.  It's BS and anyone would be a fool to trust that advise  |
Not really. The pressure on the side wall is the maximum cold pressure at the maximum rated weight. Yes the tire heats up and pressure goes up but this is allowed for by the design of the tire with safety margin. Not sure how else you would do it in the practical sense. If you put the max hot rating on the tire, how would you expect someone to measure that - how much driving to achieve max pressure? what ambient pressure? What road The choice to make it cold is a little arbitrary because it isn't based on a specfic ambient temperature either but it is practical because one is more likely to measure the tires before driving rather than driving for a while then stopping to measure.
One would be more foolish to issue a product to the consumer with small safety margins. Safety margins should be added to make sure only a fool could hurt himself - it should be clear the fool well exceeded the design parameters before something catastrophic occurred. Lawyers and lawsuits factor heavily in the design of consumer products for just this reason. Variations in manufacturing drive safety margins out even further.
I heard a story about twenty years ago when I lived in Hawaii about a kid who was killed pumping up an automobile tire. The story was he believed since auto tires are beefier than bike tires, they should be inflated higher than bike tires. Bike tires easily exceed 80-100 psi. The auto tire exploded killing the kid. Might be urban legend, who knows.