How do you measure slope angle, a large protrator?
06-08-08, 03:33 AM
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How do you measure slope angle, a large protrator?
Is there a software product or website that allows you to determine slope angle for your rides?
Thanks as always,
RFC
Thanks as always,
RFC
06-08-08, 03:46 AM
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Grade % = (vertical gain / horizontal distance) * 100
Horizontal distance is not the distance you travel though, since you're cycling up the incline (think "hypotenuse").
So if you gain 200m over a 3km ride (I'm in Europe - metric it is ...
), the horizontal distance would be X, where:
X^2 + (200m)^2 = (3000m)^2
X = 2973m
so gradient = 200/2973 * 100 => 6.7%
Basically, if you know the vertical gain between two points (bike computer with altimeter, Google Earth, etc) and you know the distance covered by road between those two points (bike computer, Google Maps [heh - can you tell I work for Google? :-P ], etc), you can calculate the average % grade.
Horizontal distance is not the distance you travel though, since you're cycling up the incline (think "hypotenuse").
So if you gain 200m over a 3km ride (I'm in Europe - metric it is ...
), the horizontal distance would be X, where:X^2 + (200m)^2 = (3000m)^2
X = 2973m
so gradient = 200/2973 * 100 => 6.7%
Basically, if you know the vertical gain between two points (bike computer with altimeter, Google Earth, etc) and you know the distance covered by road between those two points (bike computer, Google Maps [heh - can you tell I work for Google? :-P ], etc), you can calculate the average % grade.
06-08-08, 04:05 AM
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So a constant 45 degree slope is a 100% grade. Steepest streets are 35-37% grade
Some interesting pictures on this site
Some interesting pictures on this site
06-08-08, 06:35 AM
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If you're looking for a pocket tool to measure the actual angle, stop by any large shop that caters to backcountry skiers, such as REI, MEC or the like. Measuring slope angle is a critical step in assessing a given slope's snow stability, and the tool used is essentially a small card with a protractor and a weighted indicator needle. Simple, but it works.
06-08-08, 07:31 AM
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Any bike computer that measures elevation should have a readout for grade. You can also get one of these:
06-08-08, 07:52 AM
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Grade % = (vertical gain / horizontal distance) * 100
Horizontal distance is not the distance you travel though, since you're cycling up the incline (think "hypotenuse").
So if you gain 200m over a 3km ride (I'm in Europe - metric it is ... ), the horizontal distance would be X, where:
X^2 + (200m)^2 = (3000m)^2
X = 2973m
so gradient = 200/2973 * 100 => 6.7%
Basically, if you know the vertical gain between two points (bike computer with altimeter, Google Earth, etc) and you know the distance covered by road between those two points (bike computer, Google Maps [heh - can you tell I work for Google? :-P ], etc), you can calculate the average % grade.
Horizontal distance is not the distance you travel though, since you're cycling up the incline (think "hypotenuse").
So if you gain 200m over a 3km ride (I'm in Europe - metric it is ...
), the horizontal distance would be X, where:X^2 + (200m)^2 = (3000m)^2
X = 2973m
so gradient = 200/2973 * 100 => 6.7%
Basically, if you know the vertical gain between two points (bike computer with altimeter, Google Earth, etc) and you know the distance covered by road between those two points (bike computer, Google Maps [heh - can you tell I work for Google? :-P ], etc), you can calculate the average % grade.
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“Courage is going from failure to failure without losing enthusiasm." (Churchill)
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“Courage is going from failure to failure without losing enthusiasm." (Churchill)
"I am a courageous cyclist." (SpongeDad)
