So I made an equation...
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So I made an equation...
for climbing.
First off, I apologize for the mixed units. They are just what I'm most familiar with...
v= speed in mph
P= power in watts
m=mass (weight) in lbs.
g=grade (6% grade would be entered as 6)
d=distance in miles of the climb
t= time in minutes to get to the top
first:
v=50P/(m*G)
t=1.2dmg/P
Boring I know but here's what i've learned:
For my weight (200lbs including the bike) and a 7% grade, losing 10 pounds off my ass or my bike is the same as increasing my power by 20 watts. 5 pounds gets me 10 watts.
For a climb that generally takes me 11 minutes, I can cut 17 seconds off that time by losing 5 lbs. or gaining 10 watts of power.
This is in the context of climbing and thus ignores air resistance.
hope it's helpful to someone.
B.
First off, I apologize for the mixed units. They are just what I'm most familiar with...
v= speed in mph
P= power in watts
m=mass (weight) in lbs.
g=grade (6% grade would be entered as 6)
d=distance in miles of the climb
t= time in minutes to get to the top
first:
v=50P/(m*G)
t=1.2dmg/P
Boring I know but here's what i've learned:
For my weight (200lbs including the bike) and a 7% grade, losing 10 pounds off my ass or my bike is the same as increasing my power by 20 watts. 5 pounds gets me 10 watts.
For a climb that generally takes me 11 minutes, I can cut 17 seconds off that time by losing 5 lbs. or gaining 10 watts of power.
This is in the context of climbing and thus ignores air resistance.
hope it's helpful to someone.
B.
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It's also assuming that the weight lost is not muscle, because the real key is watts per kg. Sometimes losing weight will actually lose you watts as well.
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#4
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You might want to look at https://www.analyticcycling.com. They've done the work for you and you get to include all effects in all conditions without having to assume any, e.g. rolling resistance, are negligible.
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holy sheep. that website rocks. still proud of my work but thanks for the link.
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If you want to play with the formulas more on your own, get from the library or buy a copy of Bicycling Science 3rd edition from MIT Press. An entire chapter is devoted to the bicycle power equation; that plus the info on analytic cycling and a good spreadhseet or graphing program and you can spend hours at least as productively as on bf
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Analyticcycling is where I discovered that if I spent $4000 for a bike 10 pounds lighter than the one I currently ride, I would get to work a whole 14 seconds sooner.
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also take a look here https://www.kreuzotter.de/english/espeed.htm
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Originally Posted by merlinextraligh
also take a look here https://www.kreuzotter.de/english/espeed.htm
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Originally Posted by badkarma
Yeah, that's a better resource. Upon a cursory look, the OP's equations look correct, but the full-blown equations are 2nd order ODEs that need to be numerically-integrated due to their non-linear nature - so that'll give you much more accurate results.
thank god there are online calculators for this. Calculus was way too many years ago.