I have found that many rims (mostly cast) the heavy spot is not where the valve stem is. But on all 4 of my GSA rims it is due to the TPMS. Some tires don't have a mark for the light spot. If not I balance the rim first and after mounting (before seating the bead) I put it on the balancer again to find the light spot and then spin the tire so that spot is at the heavy spot on the rim. I learned from flying and working on helicopters for many years those vibrations go somewhere. On a motorcycle, bearings, drive-train, suspension, frame, and to the seat (rider comfort). Probably the most negative effect of not balancing would be a shorter wheel bearing life. So I always balance any tire I mount.
2017 BMW GS Adventure Triple Black
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