I posted 100°F in the survey, but it's really a moving target for me. If just riding to nowhere/scavenger hunting/etc. I think 90°F or a little over (in SE Texas humidity) is about all I will subject myself to. On the other hand, if traveling or something needs to done/delivered I will consider higher temperatures, assuming that my arriving soaked in sweat is acceptable for whatever task is at hand. The wife's tolerance, however, is probably 5° to 10° lower than mine before she reminds me we have other transportation at our disposal that have functioning air conditioners.