A better argument for today - how much weight matters
06-18-14, 09:53 AM
#1
out walking the earth
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A better argument for today - how much weight matters
One bike weights 1/4 pound more than the other. How much of a difference does it make over an hour going up hill?
06-18-14, 10:14 AM
#2
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How steep is the hill ?
https://kreuzotter.de/english/espeed.htm
At 300 watts, save 1 minute over 10 miles at 10% (according to them.... sounds like too much)
Calculator seems to not work correctly. I change variables, but the result sometimes stays the same.
https://kreuzotter.de/english/espeed.htm
At 300 watts, save 1 minute over 10 miles at 10% (according to them.... sounds like too much)
Calculator seems to not work correctly. I change variables, but the result sometimes stays the same.
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Last edited by Homebrew01; 06-18-14 at 10:27 AM.
06-18-14, 11:02 AM
#4
Making a kilometer blurry
What's the total elevation gain on the hill in question?
You're looking at 0.1134kg.
Force required to lift it F=ma, so F = 0.1134kg * 9.8m/s^2 = 1.111N
Work = F * d = 1.111N * elevation gain in meters. For a 3000ft climb, it's 914m, so 1.111N * 914m = 1016Nm = 1016J of work
If you spend an hour climbing this hill, you've 1016J / 60*60s = 0.28J/s = 0.28W to get this 1/4 lb. up the hill at that pace.
So just substitute your elevation in meters and the Strava KOM time for duration and recalculate.
You're looking at 0.1134kg.
Force required to lift it F=ma, so F = 0.1134kg * 9.8m/s^2 = 1.111N
Work = F * d = 1.111N * elevation gain in meters. For a 3000ft climb, it's 914m, so 1.111N * 914m = 1016Nm = 1016J of work
If you spend an hour climbing this hill, you've 1016J / 60*60s = 0.28J/s = 0.28W to get this 1/4 lb. up the hill at that pace.
So just substitute your elevation in meters and the Strava KOM time for duration and recalculate.
06-18-14, 11:24 AM
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33 seconds of you're racing
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06-18-14, 12:22 PM
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06-18-14, 12:24 PM
#8
out walking the earth
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I'm not thinking. Just looking to start a weight weenies argument.
the bikes are same, but for 1/4 pound difference in the groups.
the bikes are same, but for 1/4 pound difference in the groups.
06-18-14, 12:41 PM
#9
Making a kilometer blurry
06-18-14, 12:43 PM
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well my question would be what would the advantage of using the heavier bike be 
If you can go lighter I say go lighter. My thought process has always been go as light as possible until it starts becoming less aero or less stable to handle. That or the $$ just is not worth the marginal gain .
I do know that if I was 10 pounds lighter in one of my April road races that I wouldn't have been dropped.
If you can go lighter I say go lighter. My thought process has always been go as light as possible until it starts becoming less aero or less stable to handle. That or the $$ just is not worth the marginal gain .I do know that if I was 10 pounds lighter in one of my April road races that I wouldn't have been dropped.
06-18-14, 12:59 PM
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06-18-14, 01:15 PM
#14
out walking the earth
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06-18-14, 01:16 PM
#15
Making a kilometer blurry
06-18-14, 01:26 PM
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Strava Segment | Whiteface Hillclimb
According to Bike Calculator 0.25 lbs is worth 3.6 minutes [edit: seconds], making some other reasonable assumptions.
According to Bike Calculator 0.25 lbs is worth 3.6 minutes [edit: seconds], making some other reasonable assumptions.
Last edited by globecanvas; 08-22-14 at 12:46 PM.
06-18-14, 01:28 PM
#17
out walking the earth
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06-18-14, 01:31 PM
#18
out walking the earth
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Strava Segment | Whiteface Hillclimb
According to Bike Calculator 0.25 lbs is worth 3.6 minutes, making some other reasonable assumptions.
According to Bike Calculator 0.25 lbs is worth 3.6 minutes, making some other reasonable assumptions.
gees that can't be true can it? jinkies, just losing all the extra clothes I normally haul to the top, along with the repair stuff, and using race wheels dear god I'm losing pounds. I'm going to rip a hole in the god damn space time continuum.
06-18-14, 01:32 PM
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How much does a McDonalds quarter-pounder weigh?
06-18-14, 01:49 PM
#23
Making a kilometer blurry
Yeah, I'm seeing a difference of 0.38W to maintain speed with the extra 1/4 lb, assuming you'll be in a break with somebody, and in the pack before that, your time will actually be the same. Throughout most of the race, you'll be costing yourself a whole 1/3 of a Watt.
I say I still win, because power needed to keep up is the important figure, unless this is a time trial.
It's still ****ing deflating though.
I say I still win, because power needed to keep up is the important figure, unless this is a time trial.
It's still ****ing deflating though.
06-18-14, 01:54 PM
#24
out walking the earth
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mass start hill climb. it shatters though and everyone rides alone.
for 3 seconds I'll just ride the bike I keep up there so I don't have to bring extra stuff back and forth
for 3 seconds I'll just ride the bike I keep up there so I don't have to bring extra stuff back and forth
06-18-14, 01:54 PM
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But wait...what if that 1/4 pound is in the wheels because, you know ... rotational weight. 3.6 seconds could become 3.611 seconds.