Originally Posted by
trekker pete
Assuming a good wheelset and properly inflated tires, I believe the rolling resistance differences are negligible.
Weight is a different story. Twice the weight means twice the force.
Aerodynamics I think are a bit of a factor, but, I don't think they come close to the weight factor.
So, yes, fat dude will pwn skinny guy on the downhills, assuming he is a fit fat dude.
Of course, he will give it back, plus interest when it's time to climb, so, you ain't gonna see many XXL yellow jerseys.
However, does twice the force equate to twice as fast down the hill?
Regardless of somethings weight, his Acceleration is what is important for the downhill race.
Force=Mass*Acceleration
Acceleration=Force/Mass
In other words, while the guy twice as big recieves twice as much force from gravity, he also has twice as much mass which cancels out the benefit.