Originally Posted by EventServices
Some of it has to do with your own strength-to-weight ratio.
In very general terms:
I weigh X, and I can exert Y.
If I lose weight, I will weigh X-3, but it's also possible that I will then exert Y-3 (or Y-2.746 or maybe Y-1.984)
If I'm 185 and I ride a bike that weighs 18lbs, my total weight it 203.
But if I weigh 183 and ride a bike that weighs 20lbs, I'm also 203, but will I be as fast?
But I see what you're getting at: a 300lb man shaving a bike down to <18lb is absurd.
VooDoo, check my math.
It's all relative.
3lbs for a fit and trim 150 lbs rider is more significant than 3lbs for a 300lbs guy.
Even on a climb a 1% reduction in total weight doesn't translate into a 1% reduction in total work.
You might reduce weight, but other factors like rolling resistance, drivetrain losses and aerodynamics (yes, at 10mph you still have 25% of the air resistance at 20mph) remain constant.
The upshot is you might reduce weight by 1%, but you might only reduce work by 1/2%. Of course the reduction in work correlates with the steepness of the climb.