I'm currently riding a Trek 7500. On a 20 mile ride yesterday I averaged 18m/h. This includes brief stops at lights, etc., so I'm not sure what the actual average speed is.
But what I am wondering is this: given the same rider (me) with a fairly decent road bike, how much of a difference in average speed can I expect?
I know there are probably too many variables to give a precise answer, but is there a ballpark percentage as how much faster, on average, one can go with a true road bike as compared to a hybrid. After all there would be less weight, less rolling resistance, and less wind resistance (due to lowered riding position).