Originally Posted by
JerrySTL
I have a nice CF road bike and a steel touring bike that weighs about 10 lbs more. I'm about 2-3 mph faster on the road bike on flat roads. In the hills I'm even slower on the touring bike.
However the touring bike has much fatter tires (700x32 vs 700x25) which along with the wider wheels makes the bike not as aerodynamic. Speaking of aerodynamics, I sit much more upright on the touring bike.
Therefore while I think that the weight slows me down, it's probably the smallest part of the issue.
FTFY. On flat ground, aerodynamics are dramtically more important than weight. 10lbs of weight on the flats, will make a tiny difference in speed. (Small enough, the rounding doesn't show it in Kruezotter). 10lbs on the hills will be noticeable, but we're talking around .1mph. Whereas an upright position on the flats can be as much as 2 miles per hour difference, compared to a more aero position.