I am toying with the idea of riding my '91 DR350S 1000 miles each way from eastern North Dakota to SE British Columbia, on highways the whole way. Once I get to BC I will see steeper rocky logging roads that require lower gearing. Currently my bike is set up so it's at 6000 rpm at 60 mph. I read that this is a good middle ground for dual sport riding. However I would like to overdrive it a bit more to get the RPMs down a bit and cruise at as low of RPM as possible at 65 mph. It does have the power for any taller gearing on the pavement right? Or is there a point you get to that you start lugging the engine and mpg goes down and temps go up or something? I would then like to bring a smaller sprocket and swap its place with the larger one once I get into BC. This is only a 10 minute job or so and seems to make a lot of sense to me. Does anyone else do that? Also, kind of a newbie question, but what is the gearing cable fed off of? Will the speeds be correct for say a 13 tooth AND a 15 tooth sprocket? I do not think so, but I thought I would ask. I have a feeling with the larger front sprocket I will be a few mph faster than indicated and with a smaller front sprocket be a few mph slower than indicated.