I'm curious about changing the gear ratio on the G650GS. I am planning a cross-country trip, or at least an attempt at one (hopefully the bike will fail gracefully). Looking up available sprockets, I note that it should be theoretically possible to regear it to 17/39 from 16/47, a 28% increase in speed at gearing or a 22% decrease in gear ratio. In theory, this should turn the 5th gear into an overdrive gear, and since I'm competent enough using only 2nd gear, the loss of low-end power shouldn't be too bad. Most importantly, for me, I prefer riding in the 2500-3000 rpm range, and this allows me to get 50 mph on 5th gear.
However, when I talked to my dealership to order the parts, they seemed shocked, and mechanics actually suggested I'd have to push-start it if I made such a change. Why is there such an aversion to radical overgearing? And why does only a 22% decrease in gear ratio frighten people? Am I seriously chasing a chimera? Could someone with experience on the topic help out?
However, when I talked to my dealership to order the parts, they seemed shocked, and mechanics actually suggested I'd have to push-start it if I made such a change. Why is there such an aversion to radical overgearing? And why does only a 22% decrease in gear ratio frighten people? Am I seriously chasing a chimera? Could someone with experience on the topic help out?