% Grades Defined

[Nanci]

(Found this when I was trying to document for someone that total elevation gain for a ride is a good measure of difficulty).


* 0% grade is exactly flat (and a negative grade, less then zero, is downhill).

* 2% grade does not seem very steep, but it's enough to substantially reduce forward speed, and for most riders it will absorb more than half their power output.

* 6% grade is enough to cut speed to well under half, and absorb more than 80% of a rider's power output (leaving less than 20% to fight air resistance and rolling friction).

* 10% grade, and anyone who is not a fit and frequent rider is off their bike walking -- and anyone who is not a racer is reaching for all the extra power they've got.

(Hmmm, they didn't go up to 22%!! Well, I know I can ride 7% for several miles, but it isn't pretty, and I'm riding at 4mph, which is about a quarter of my average speed!!)

[maillotpois]

That's fascinating!

I know the one section of Pine Flat that's 21 - 22% for about 1/2 mile was too much for me. I had to put my foot down and ended up walking a bit. (I was also still sick and started wheezing, and I really didn't want to start hyperventillating there!)

In the Giro, the riders will do a section of road - unpaved - that goes to 24%!! Amazing!! Should be a great spectacle.

[fatbottomedgurl]

Thanks Nanci! I noticed something interesting. Often when I do a climb, and get to a level stretch, I look to the side and realize I am still climbing, it's just not as steep! I love that! I can tell my body is getting stronger every time I go out. Isn't cycling awesome?!

[Eden]

The worst I've been up was 26%! It was so steep that the front wheel of the bike kept lifting up off of the pavement and I ended up having to get off or fall off.

We have some other stretches of gradients in the high teens / 20's around here. Most everyone has to stand to be able to get up something that steep. If you get off you won't be able to get back on - impossible to get started again.

[Dianyla]

* 6% grade is enough to cut speed to well under half, and absorb more than 80% of a rider's power output (leaving less than 20% to fight air resistance and rolling friction).
Hmm, well at 5mph I suppose I don't have to worry so much about air resistance. :p

[maillotpois]

Hmm, well at 5mph I suppose I don't have to worry so much about air resistance. :p


That's classic! At the Mt. Tam Double, I was doing some climbs at 3 mph, and DH was about ready to push me over!

[Dianyla]

That's classic! At the Mt. Tam Double, I was doing some climbs at 3 mph, and DH was about ready to push me over!
And isn't it the worst when the weather's already warm out and then on some bigarse hill your fresh speed-generated breeze goes away because you're going so slow?

:mad: <-- the way my face looks climbing big hills

[maillotpois]

Yes - it's like you're suddenly going backwards. Nice face! I am trying to perfect the "Dead Elvis Look" (see Lance Armstrong's War).

[Dianyla]

Yes - it's like you're suddenly going backwards. Nice face! I am trying to perfect the "Dead Elvis Look" (see Lance Armstrong's War).
Never heard of it. Does this involve an asymmetrical sneering upper lip? :rolleyes:

[maillotpois]

Never heard of it. Does this involve an asymmetrical sneering upper lip? :rolleyes:

It's a book by Tim somebody (SK will remember the name). Anyway, it's very entertaining and he talks about how the pro riders look like crap when they are working their butts off to drop someone. And Lance has this "Dead Elvis" look - sort of his poker face. It was funny, but now I can't remember the exact description.

[Nanci]

Hey, I'm re-reading Lance Armstrong's War right now- I can find that quote! I _know_ I was doing the Dead Elvis Look Saturday...

[bikerz]

But the nice thing about that slow speed up a hill is there's plenty of time to watch the roly-poly bugs cross the road in front of me, and check out the contruction progress on the new houses they are building.

2.6 mph is the slowest I've ever gone on a hill, and of the 20% left to fight air resistance and rolling friction (that is a funny idea at that speed!), 99% was probably being used for balance!

I got passed by a jogger on Saturday on my local hill ride, but he was a young fit guy. At least I can pass the two little old ladies who take their daily walk up that hill!

[Bike Goddess]

Hey Biker Z- Just remember that hill will make you STRONG!!!!!:D :D :D :D

[bikerz]

Oh I know! That's what I tell myself as I slog up, a little faster every time!

[SadieKate]

Yawl will be very please to know, I'm sure ;), that my compooter says the climbing on the Wine Country Double Metric averages out to 6%.

[annie]

You know its a steep grade when you are riding so slowly that the annoying flies and gnats keep up to you and buzz around your head and you can't even ride fast enough to escape them! :( You don't even want to waste the energy it takes to swat them away.

annie