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Eelevation Gain ?(17 posts)

Eelevation Gain ?PatM
Sep 12, 2002 3:59 PM
How is elevation gain determined for a given ride ? I have topo USA and comparing that(Climbing Elevation) to numbers I found posted for a given ride they don't match up.
Any one out there determine elevation gain for a ride they have done ?
re: elevation Gain ?collinsc
Sep 12, 2002 4:18 PM
your program probably just tells you the difference between the start and stop.

total elevation gain is total feet gained over the whole ride.
Topo mapsKerry
Sep 12, 2002 4:29 PM
The problem with Topo maps is that they do not show all of the up and down - the road can be rolling between the topo lines and the map won't show it.
who's right?DougSloan
Sep 12, 2002 7:49 PM
Who says the numbers posted are right? They might have guessed, or used a bike altimeter, which are notoriously way off (usually indicate too high numbers for total gained).

Topo has a 20 foot resolution, I think. I doubt anyone is going to do better than that.

I'd trust topo more than any other source, unless it was a surveyor.

Doug
Maybe one of the new hi rez GPS thingies? -nmSnowBlind
Sep 12, 2002 9:39 PM
who's right?PatM
Sep 13, 2002 2:51 AM
Its just funny a century that I did last week whic is flat, one website has less than 2000 elev gain, another web site has 3500 elev gain and I think topo has about 4200 elev gain. The funny part of the whole thing is that the min elevation is sea level and the highest hill is around 300 feet, just lots of rollers add up to high elevation numbers.
I looked at the profile for a very small section of the ride and as you move the cursor over it you can see it only counting elevation as it goes up.
So let me ask you this when you see a ride that you want to do and you don't know the area, do you always try and put it into topo to see what its really like ? Its really one of the best software buys that I have made in the past two years.
Climbing 50 ft 50 times doesn't equal a 2500 ft. climb.dzrider
Sep 13, 2002 4:12 AM
Moreover climbing 2500 feet @ a 5% grade is way different than 2500 feet at a 10% grade. Every climb hurts you a whole lot more 100 miles later. All this leads me to conclude that a total elevation number can paint a very misleading picture of the difficulty of the ride.
I agreePatM
Sep 13, 2002 5:33 AM
I agree, I guess I wish more rides either provided a profile, of the ride, or a cue sheet before the ride. I know some rides don't want to provide a cue sheet because you may get more people not registered for the ride, so its a tough choice.
But I know its hard around here anyway to get good info on what the ride is like before doing it.
The first 20 ft are often free ...Humma Hah
Sep 13, 2002 3:05 PM
... in close-spaced rollers, you can use the energy for going downhill to coast up the next hill. I can ride 20-ft close-spaced rollers about as easily as flat terrain. Those are rare, of course.

I don't think the first 20 ft of a hill counts, so lots of 50-footers are basically really 30-footers, and you gotta discount the climb 40%.

I agree, the stand up, watch-your-pace climbs, the ones that will waste you if you climb with your legs instead of your head, are a whole different animal than short climbs.
Topo USA is very inaccuratemr_spin
Sep 13, 2002 6:21 AM
I have Topo USA and it comes up with bizarre numbers. I did a simple route up a mountain in the San Francisco Bay area called Mt. Diablo, and it somehow calculated 1,000 feet of climbing on the way down!. I've done other routes and gotten similar effects. I think they should label the feature "For entertainment purposes only."
Topo USA is very inaccurate - Not NecessarilyB2
Sep 13, 2002 6:47 AM
I believe the problem comes in "tracing" your route. If you waver much with the mouse, your traced route deviates above and below the actual road or trail. This erroneously adds to the descent and ascent totals.

One possible solution (with TOPO) is to use the magnify option. When you are at 200% or 300% scale and you slip say a 1/4" or 1/2" with the mouse it's a much more minor off-route variance.

I've found that my Suunto altimeter watch and TOPO to be VERY VERY close regarding altitude gain/loss time and again using this method. The two might vary a couple hundred feet over 5,000'+ climbing. To me this suggests that there is likely a degree of accuracy involved.

Then again, I haven't tried to use TOPO for rolling terrain. I could see how the accuracy in this scenario might be suspect. I've typically used TOPO for routes that may have several climbs, but sustained ones just the same.

That's My 2 Cents,
Bryan
Totally different programmr_spin
Sep 13, 2002 7:17 AM
You don't trace routes in Topo USA. You select waypoints and it calculates the route for you. So there is no possible user error here.

You are talking about another program from another company called TOPO. I also have that one, and it is infinitely more reliable for calculating gain as long as you are at level 5. It is a lot more painful to use.

I wish the two companies would get together and create a single program that has simple route selection and reliable gain estimates. Is that so much to ask?
Totally different programsnapdragen
Sep 13, 2002 5:23 PM
mr_spin and other SF Bay Area riders, check out Bike Master.

http://bikemaster.home.att.net/index.htm

I don't know how accurate it is, but I do have fun making my own rides up.

I'm curious to see what others think of it.
Topo 2 vs. 3 & 4DougSloan
Sep 13, 2002 7:21 AM
With 2.0, you had to do your route by hand, placing all your waypoints. With 3.0 and 4.0, you route it like Street Atlas, and it automatically traces the route. That would most eliminate that problem. I say "mostly," because it still deviates from the road path here and there, and sometimes you can't even "force" the route back onto the road.

Also, make certain you are looking at the correct information; there is total ascent, net ascent, etc. Don't confuse the info, and always give it sort of a "reality check," comparing the numbers with a visual inspection of the profile, subtracting the peaks and valleys.

Also, I think it's much more accurate when dealing with large variations, like 1,000 foot or more climbs; little rollers are subject to a whole lot of cumulative error.

Doug
re: Eelevation Gain ?Rom12_1
Sep 13, 2002 7:51 AM
Where have you picked up the software? I haven't heard of it. This can be used for any smaller roads in the US? What's the cost? Thanks! S
Related topic: do I have my work cut out for me tomorrow?hrv
Sep 13, 2002 11:44 AM
I'll be in a bike race tomorrow in Camas, WA and here's the profile:

http://www.wordsports.com/nrrcamasroadracemap2.htm

Accurate or not, I think I'm gonna be hurtin' !

hrv
all races with hills hurtDougSloan
Sep 13, 2002 12:30 PM
I've never seen a hilly race that did not hurt really bad. Flat roads, you can sit in and chat all day long. Hills always test the limits. I've seen worse, but 1,000 foot climbs are enough to hurt really bad, depending on what sort of climber you are compared to your competitors.

Good luck.

Doug