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Posted: Fri Jun 13, 2008 2:00 am
by RocketGirl
2007 Yamaha Virago 250

It's my first ride, just over 200 miles now and the manual said I need 1000 miles to break it in. So, I'm a bit hesitant of opening the throttle more for these 'hills'. :?

Posted: Fri Jun 13, 2008 2:03 am
by jonnythan
Check this out.

It's "the world's steepest road." It's located in New Zealand and it's called Baldwin Street.

Image

Holy steep, right?

Well, the maximum slope of the street isn't even 20 degrees. It's a 35% grade. There are some other streets listed in the article that may be slightly steeper, but all are well under a 40% grade (and thus right about 20 degrees or less).

The article even claims that a 79% grade would be "impossible to walk up."

Suffice to say, that "~50 degree" street is a lot closer to 15 than 50.

Posted: Fri Jun 13, 2008 2:47 am
by the_sandman_454
2007 Yamaha Virago 250

It's my first ride, just over 200 miles now and the manual said I need 1000 miles to break it in. So, I'm a bit hesitant of opening the throttle more for these 'hills'.
If you don't want to use the throttle "too much" then being in the correct gear is even more critical. I personally wouldn't be all that paranoid about throttle usage as engine speed though.

So if you're using more throttle than you like to maintain speed or accelerate, downshift.

Posted: Fri Jun 13, 2008 3:03 am
by motokid
jonnythan wrote:
dr_bar wrote:snip
Dramatic picture, but it looks more like 50-60% grade to me, if that. You can't really just comfortably sit sideways on the curb of a 100% grade slope.

I've done some inclinometer work for various outdoor stuff, and I've always been surprised at how much lower grades are than they appeared to me. Some ski slopes I would have sworn were about 45 degrees ended up more like 30 or 35. Hiking up a 100% grade on a mountain is really, really hard and really, really steep. I've seen steep roads but I've never seen anything that actually approaches a 100% grade.

Ah well. :)
You guys must have skipped lots of high school math classes to go out riding - lucky you :).

100% = 90 degrees - absolute vertical
70.4% = 45 degrees - 'half' vertical
10% = 5.7 degrees - rather steep for highway

incline in % = elevation gained / road traveled * 100

K

Posted: Fri Jun 13, 2008 3:28 am
by jonnythan
motokid wrote:You guys must have skipped lots of high school math classes to go out riding - lucky you :).

100% = 90 degrees - absolute vertical
70.4% = 45 degrees - 'half' vertical
10% = 5.7 degrees - rather steep for highway

incline in % = elevation gained / road traveled * 100

K
100% grade is 45 degrees.

Grade is measured as the tangent of the slope. In other words, grade is the ratio of "rise" to "run." If you travel 100 feet horizontally and 100 feet vertically, you have traveled a "road distance" of 141 feet. You are comparing the "road distance" to the vertical distance.

I dunno if that's correct for "incline," but "grade" is the former. 100% grade is 45 degrees.

This can be confirmed by, among other things, the sign at the bottom of Baldwin Street itself. It lists the grade as "1 in 2.86," which is about 35%. Given the slope is about 19 degrees, your method would result in a grade closer to 1 in 3.

In any case, the acknowledged steepest streets in the world max out at a 20 degree slope, a far cry from the "close to 45 degree" or "~50 degree slope" claimed ;)

Posted: Fri Jun 13, 2008 4:14 am
by motokid
jonnythan wrote:
100% grade is 45 degrees.

Grade is measured as the tangent of the slope. In other words, grade is the ratio of "rise" to "run." If you travel 100 feet horizontally and 100 feet vertically, you have traveled a "road distance" of 141 feet. You are comparing the "road distance" to the vertical distance.

I dunno if that's correct for "incline," but "grade" is the former. 100% grade is 45 degrees.

This can be confirmed by, among other things, the sign at the bottom of Baldwin Street itself. It lists the grade as "1 in 2.86," which is about 35%. Given the slope is about 19 degrees, your method would result in a grade closer to 1 in 3.

In any case, the acknowledged steepest streets in the world max out at a 20 degree slope, a far cry from the "close to 45 degree" or "~50 degree slope" claimed ;)
Sorry, I stand corrected. English is not my first language so I confused formal 'road' meanings of words 'slope', 'grade', incline', 'rise' e.t.c. Thanks.
However, the point in question stays, numbers quoted were to high to describe real world really steep streets.

K

Posted: Fri Jun 13, 2008 3:41 pm
by Hondagirl
Never mind. I didn't understand it either and English is my first language. Fascinating though.
No hitchhikers on that hill then.