I race bikes in my spare time and someone asked this on a cycling forum:
How much time could you save on a 40km race on a flat course, riding at 40km/h if your bike was one pound lighter. Let's say the weight of the rider and bike together is 80kg.
There was a time when I was younger when this would be trivial but right now I can't figure it out.
v = d / t
a = v - v0 / t
F = m * a
The Attempt at a Solution
So I know I have to figure out how much time it takes to do the course in both cases.
And I know I have to factor in mass somehow.
t = (v-v0)/a = (v - v0) *m / F
And this is where I get stuck. I don't know what force is required to move the bike.
Thank you in advance and sorry about my English, it's not my first language :)