i have installed quite a few tires and just learned something new. i installed a new front Tourance. it needed 2 ounces to balance at the same spot as the old Battlewing and the original Trailwing. i have read the valve stem is the heavy spot on the rim and never thought to check. but after more research i dismounted the tire and balanced just the rim. it took 1 ounce to balance just the rim. the heavy spot is not the valve stem on my wheel. with the stem at the bottom my heavy spot is at about 10:00 o-clock. i removed the weight and remounted the tire with the dots at the new heavy spot and only needed 1/4 ounce. probably not even needed.