Low tire pressures are reported on more than 50 percent of bikes inspected by repair facilities, and few riders seem to understand the dire consequences of this frequently overlooked faux pas. SmarTire, a pressure-monitoring system distributed in North America by ZTechnik (a division of National Cycle), combats the problem by signaling when tire pressure has dropped below safe conditions. An in-wheel mounted wireless transmitter and a warning LED installed on the instrument panel act as watchdogs by continuously monitoring both tire pressures. SmarTire can only be installed by authorized dealers, and only on tubeless tires; an updated version will be available later this year. The unit sells for $264. (866) 983-2465, www.ztechnik.com/smartire, or (877) 972-7336, www.nationalcycle.com.