How much energy do you save by losing 1 kg of the weight of your bike (or yourself)?

If it takes 9.8 joules to lift 1 kg 1 meter, does that mean I’d save 9,800 joules over 1000m of vertical climbing, which is only 2.3 kcals.

This seems a very small number, guessing my maths is totally wrong.

Trying to give myslef some motivation to lose a few KGs.

energy = mgh

1kg x 9.81 x 1000m = 9810 joules.

lets say you're climbing a 1:20 gradient = 20km.

let's say you climb it in 1 hour (20kph) = 3600 seconds

power = (energy / time) = (9810 / 3600) = 3watts

not a lot, about 1% extra effort for a fit rider.

enough for racers to worry about, – me? worried? not so much.

(i'm a skinny wretch, my gp told me to eat more chips)

actually muscles are only between 20 and 25% efficient, so the saving is roughly 4 or 5 times bigger 🙂 Figure about 1kCal per metre for a 100kg all up rider, bike & kit

This plug in at analytic cycling reckons you'll be .88 secs quicker; put the fork down and step away from the fridge…

http://www.analyticcycling.com/ForcesLessWeight_Page.html

weight off you – you'll feel better.

weight off bike – it'll feel better to ride (moreso if weight lost from wheels).

Actual difference – not significant for most of us apart from the above.

Guess I'll just have to look in the mirror for weight loss motivation 😯

BTW, where is that hill ?