eh, i dont see it mattering a great deal, cause the sidewall will stretch a little for a slightly larger rim...but i do agree, if the sidewall is pulled out too much for too large of a rim, it could be dangerous while in a turn because your losing some of that support.



you can see bike tires are not like conventional car tires, with a straight perpendicular sidewall. bikes sidewalls are meant to be perpendicular while leaned over. thats where stretching the tire to the rim comes into play. i feel there is a wide enough selection out there that you can find something that meets your specific, or relatively specific needs, and you wont have to compromise safety by using odd tire/rim combo's.



and yes, the graph is decieving, the 180 is 10mm less wide apex to apex than the 190's and that is illustrated, but your right, they dont say what size rim it would be used for.