rise/run

To calculate it mathematically, the simplest way requires that you know the elevation gained and the distance traveled. For example, if you gain 300 feet elevation over 3000 feet traveled, then the grade is 10% (300/3000=0.1).

Otherwise, you can buy a simple little device that hooks onto your handlebars and uses a level-bubble device to show grade.

well see I remember the forumla, the only problem now is that I don't have the implements. Back in school everything was nicely placed on a graph for you. Any "cheap" ways to figure out the rise portion, the run portion is easy.

http://www.topozone.com

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"Go yell at an M&M"

YOu know now that I think about it the "run" portion of it isn't quite easy to figure out either because you're actually riding up the hypotenuse, which is actually a bit longer than the flat "run".



Now I'm lost....ideas?

Do you have an account with them? Is it pretty good? 49 a year seems steep when for the most part I don't care about elevation and such (I live in Iowa, hills are few and far between)

Compared to the Tour, a half mile hill wouldn't even register. Categories are explained here. http://www.faqs.org/faqs/bicycles-faq/part1/section-22.html

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clm
Nashville, TN
https://twitter.com/ironclm | http://ironclm.typepad.com

Go to lower left, enter city and state, then change map size/detail to suit. Free.

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"Go yell at an M&M"

Let me know where the road is and I can put it into TOPO and get elevation grade etc and let you know...if you're not in a big hurry. Won't be home this weekend.

~Matt

A guy in our roadie group has a bike mount GPS that tells him exactly the gradient on each hill. Kind of a neat toy.

Where does it say the elevation?

deckdrain
Where in IA are you?
I'm from central IA!

[reply]Compared to the Tour, a half mile hill wouldn't even register. Categories are explained here. http://www.faqs.org/faqs/bicycles-faq/part1/section-22.html[/reply]

Over the years, I have gathered statistics about all the climbs in the
Tour. It is summarized at
http://xenon.stanford.edu/~walker/tdfclimbs.html

The rec.bicycles FAQ (this part - written by Bruce Hilden) is pretty accurate
with regards to the general description of the categories. But his
characterization of some US climbs do not agree with the numbers from
recent TdFs. As an example, he says that Palomar Mountain might
be make it as high as cat 1, but the recent history puts its length
and grade clearly in the HC range. I have not ridden in Europe,
so I really cannot compare the climbs on a personal basis.

Regarding grade calculation, dividing rise (altitude change) by
length gives a pretty good approximation of grade for most
roads (within 1%). Of course, to get a better approximation,
you can compute the run, which is approximately equal to
the square root of length^2 - rise^2 (Pythagorean Theorem).

For determining elevations, you can either get your hands on
an altimeter (I love my old Avocet 50 for this reason) or look
on the web. A number of people have suggested topozone.
For the past couple years, I have been using the free online
map server at maptech (http://www.maptech.com - under
online maps and then maptech mapserver). And if you want
to see the climbs (and you have a recent Windows machine
and a fast internet connection), try downloading Google Earth
(http://earth.google.com).

-- John

Go to google earth http://earth.google.com/ and download the product its awesome and free. you can do fly overs and zoom in.

Find the section you want and the curser will give you eleveation and Coordinates.

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Just Triing
Triathlete since 9:56:39 AM EST Aug 20, 2006.
Be kind English is my 2nd language. My primary language is Dave it's a unique evolution of English.

Iowa, Cedar Rapids. You?

Google gives "eye" elevation not elevation of surface....at least that's what I see, there might be something I'm missing, if so please advise.

Got it....in case we've lost some of you, you have to have "Terrain" selected to get elevation

If you want to do this while you are riding, I know there are several bike computers that do this (Garmin is one) or there are the handlebar mount levels that you can buy that tell you too, like someone else said. I ride with folks that use both and tell us the grade on some climbs, as we are out of breath climbing...

Im looking for a bike computer with GPS and tracking, that I can dump into my computer and show speed at different points over the coarse I rode with elevations, ect...

if i remember correctly from trig, and i probably don't, arcsin(elevation/distance traveled) gets you the angle of ascent

Math geeks feel free to correct me.

i would not consider myself a math geek, but your response sounds correct. however, instead of using the arcsin, you could also just use the pythagorean (sp?) theorum. a^2+b^2 = c^2 where c is the distance you travel on your bike. a is the vertical gain. b is the horitontal gain (basically the distance to the center of the hill if you could just drive through it.

here is an example:

your computer says you went 2.5 miles (that is C)

you know that the vertical gain is 600 feet (this is A)

you must convert miles to feet (therefore 5280 *2.5 = 13200

your equation is as follows

13200^2 = 600^2 + B^2

174240000 = 360000 + B^2

174240000 - 360000 = B^2

173880000 = B^2

B = +/- 13186

B is your run

600 is your rise

rise/run = .0455 or 4.5%

wow...never thought it would take that long, but i had to finish once i got started