Pittsburgh hills

On 26/11/12 23:18, Graham wrote:

wrote in message
...
On 26/11/2012 11:23 AM, wrote:
Article about a race in Pittsburgh's hills. 37% grade, anyone?

http://www.post-gazette.com/stories/...-dozen-663572/



or

http://tinyurl.com/booeuyl

For tech, I suppose we could discuss what equipment you'd use for
a 37% grade. On cobblestones!

- Frank Krygowski


Assumptions:

300 W continuous.

60 rpm minimum, 1 rev per second.

175mm cranks.

Percentage gradient is measured as; gradient = (elevation x 100) /
(distance travelled)

Ignoring wind resistance.

Mass of bike + rider = 90 kg.

700c wheels.

Then:

Vertical speed is given by;

P = m*g*dh/dt

300 / (90 * 9.81) = 0.34 m/s

Road speed is then;

0.34 * 100 / 37 = 0.92 m/s, or 3.31 km/h

Gearing required would be;

0.92 = wheel circumference * chainring / sprocket

0.92 approx = 2.014 * 18 / 38

I may need more Watts or a smaller back wheel.

I suspect you have a lot more watts when you consider that whilst 37%
this is only 100 yards. In your example above that's roughly 1 minute
40 seconds. My bet is that you could knock out at least 500 watts for
the 1 minute it would take you at that power level. It then becomes
an optimisation between time, strength, traction and cadence. Not
being a hill climb racer I do not have a feel for how that comes
out.



You're probably right.

A while ago someone asked what gradient hill they could ride up with
some wicked small gear. There was a lot of discussion, but I don't
recall anyone coming at it from a power perspective.

--
JS.

James wrote:
:On 26/11/12 23:18, Graham wrote:
:
: wrote in message
: ...
: On 26/11/2012 11:23 AM, wrote:
: Article about a race in Pittsburgh's hills. 37% grade, anyone?
:
: http://www.post-gazette.com/stories/...-dozen-663572/
:
:
:
r
:
: http://tinyurl.com/booeuyl
:
: For tech, I suppose we could discuss what equipment you'd use for
: a 37% grade. On cobblestones!
:
: - Frank Krygowski
:
:
: Assumptions:
:
: 300 W continuous.
:
: 60 rpm minimum, 1 rev per second.
:
: 175mm cranks.
:
: Percentage gradient is measured as; gradient = (elevation x 100) /
: (distance travelled)
:
: Ignoring wind resistance.
:
: Mass of bike + rider = 90 kg.
:
: 700c wheels.
:
: Then:
:
: Vertical speed is given by;
:
: P = m*g*dh/dt
:
: 300 / (90 * 9.81) = 0.34 m/s
:
: Road speed is then;
:
: 0.34 * 100 / 37 = 0.92 m/s, or 3.31 km/h
:
: Gearing required would be;
:
: 0.92 = wheel circumference * chainring / sprocket
:
: 0.92 approx = 2.014 * 18 / 38
:
: I may need more Watts or a smaller back wheel.
:
: I suspect you have a lot more watts when you consider that whilst 37%
: this is only 100 yards. In your example above that's roughly 1 minute
: 40 seconds. My bet is that you could knock out at least 500 watts for
: the 1 minute it would take you at that power level. It then becomes
: an optimisation between time, strength, traction and cadence. Not
: being a hill climb racer I do not have a feel for how that comes
: out.
:
:

:You're probably right.

:A while ago someone asked what gradient hill they could ride up with
:some wicked small gear. There was a lot of discussion, but I don't
:recall anyone coming at it from a power perspective.

And starting speed. If that's the begining of a hill that you can hit
with a running start, you get to trade some of your KE for PE. Even
if it's in the middle of the thill, you'll get some of that, though
not as much.

--
sig 6

On 11/26/2012 01:42 PM, AMuzi wrote:
On 11/26/2012 10:33 AM, wrote:
On Monday, November 26, 2012 5:52:03 AM UTC-5, Graham wrote:

It also looks like a CF steed with relatively high end, light weight
wheels is the weapon of choice for the majority. It would also appear
that everyone is dressed in cycling "sports" clothing - there is even
a pink sleeved jersey and shorts!!! No every day clothes in sight.
Also everyone in the 10 photos shown is wearing a helmet.

It is a race, after all. Very few racers compete on utility machines
while wearing everyday clothes. The same is true of NASCAR, by the way.

- Frank Krygowski



It's not.

You can enter a bicycle race with a wide range of equipment. Steel,
carbon, aluminum, new old, tubulars, clinchers, friction shift, whatever
you like.
(OK, no recumbents but the point remains)

NASCAR equipment is tightly regulated. Some would say overly so.


I'd be one of those people. Either make it a true stock class (roll
cage, fire extinguisher, and race tires only allowable mods) or let 'em
go nuts with the technology.

Any race class that calls itself "stock cars" but makes drivers compete
with carbureted pushrod V-8s causes my brain to asplode.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On 26 Nov, 01:28, James wrote:
On 26/11/2012 11:23 AM, wrote:

Article about a race in Pittsburgh's hills. *37% grade, anyone?

http://www.post-gazette.com/stories/...-city/with-gri...

or

http://tinyurl.com/booeuyl

For tech, I suppose we could discuss what equipment you'd use for a 37% grade. On cobblestones!

- Frank Krygowski

Assumptions:

300 W continuous.

60 rpm minimum, 1 rev per second.

175mm cranks.

Percentage gradient is measured as;
gradient = (elevation x 100) / (distance travelled)

Ignoring wind resistance.

Mass of bike + rider = 90 kg.

700c wheels.

Then:

Vertical speed is given by;

P = m*g*dh/dt

300 / (90 * 9.81) = 0.34 m/s

Road speed is then;

0.34 * 100 / 37 = 0.92 m/s, or 3.31 km/h

Gearing required would be;

0.92 = wheel circumference * chainring / sprocket

0.92 approx = 2.014 * 18 / 38

I may need more Watts or a smaller back wheel.



1200 of them for 2 minutes is a good place to start IIRC. I remember
that it didn't bother most lads that they were riding a 54" gear up a
slope of 1in4 Even the flyweights coped better with a 25mm rear
tyre (some were using 20mm at times) or 23mm tub(on wet road) probably
about 70 -75 rpm I eventually learnt my better climbing cadence was
at 85rpm, and when I applied this knowledge (after flitting
appropriate FW) could outclimb my mates on short hills. Lower gears
work, but don't go too far. Remember to use the eight muscle actions
in each full crank rotation and keep each active period constrained
within the useful angles. Back, lift, forward, down. At climbing
cadences (of steep hills), there is overlap of the muscle action, but
generally one needs to still keep it to a minimum in order to maximise
climbing speed.

I'd always been good with anaerobic efforts, just not great with the
bike, until learned a few things about my own physiological
capability. After which, I could sprint well, with the right
equipment.

On Nov 25, 4:23*pm, wrote:
Article about a race in Pittsburgh's hills. *37% grade, anyone?

http://www.post-gazette.com/stories/...-city/with-gri...

or

http://tinyurl.com/booeuyl


This is the definitive view that I know of:

http://www.frontiernet.net/~rochball...wns/canton.htm

A gnarly looking hill, all right; and the cobblestone at the top would
challenge my slalom technique, but a challenge too good to pass up if
I happened to ride by and see it.

Not real long - I only count about 60 steps or so on the sidewalk
along the steep part. So unless those are awfully high steps I don't
see how the vertical rise could be a really big number (cobblestones
may break my bones but numbers never hurt me :-) *Appears* to be
eminently surmountable.

For tech, I suppose we could discuss what equipment you'd use for a 37% grade. On cobblestones!


We could, but I believe the proof is in the pudding, and since people
are already riding up it...

(My usual bike has triple chainrings w/ a 24-tooth which I have never
used except to make sure the chain will shift to it. I imagine I'd go
to the 36-tooth front and 28-tooth rear for a first try, and if that
wasn't enough, try again with the 24-24.)

"Dan O" wrote in message ...
On Nov 25, 4:23pm, wrote:
Article about a race in Pittsburgh's hills. 37% grade, anyone?

http://www.post-gazette.com/stories/...-city/with-gri...

or

http://tinyurl.com/booeuyl


This is the definitive view that I know of:

http://www.frontiernet.net/~rochball...wns/canton.htm

[snip]

Not real long - I only count about 60 steps or so on the sidewalk
along the steep part.

[snip]

I believe you are right. If you watch the video of the race the guys who are getting up to the top of the cobbles are doing so in less than 30 seconds. They are also getting a run in to the bottom of the climb from the flat. I guess its all about picking your gear for the really steep bit over the cobbles then spinning into with as high a cadence as you can manage. You might get in one change before losing momentum but I would be inclinded not to risk it. So it looks as though it comes down to the power you can put out over a 20 second sprint providing you have picked the right gear so you do not stall.

Graham.

IS THERE A BLOOD N URINETEST ?

yaknow the time and energy spent in physical prep like years n in that time span surly there's enough dinero for at least a quasiracer....like arn't there any riders on the backside just havung a time running ?

stock cars have always been stock cars cept for Richard Petty off course....

idea is driver's race drivers nit the road or the design team or the mechanics or......engine builders and oil chemists at uh wht's their name ?

local noise suggests the hill off Washington's escape route was a bit over 30%

ungh windows vista blew out trying to get Garmin into Picasa....expletive deletd garmin is read only...Canton Ave is off the main climb to the left looking up there's a road thru the trees going to the top Ave.....Canton dead ends but short of the dead end a road runs off to the right at the crest. A road built to open up real estate. The Hasbrouck hill went up 5.5 contour lines. at abt 800'...garmin refuses a feet measurement past 560..the Giants play down there to the east... settled soon after the Indians sold the Island

On Monday, November 26, 2012 6:48:07 PM UTC-5, Dan O wrote:

Not real long - I only count about 60 steps or so on the sidewalk

along the steep part. So unless those are awfully high steps I don't

see how the vertical rise could be a really big number (cobblestones

may break my bones but numbers never hurt me :-) *Appears* to be

eminently surmountable.

Pittsburgh's steps are interesting on their own. See
http://en.wikipedia.org/wiki/Steps_of_Pittsburgh

I doubt there are many other places where some stairways are legally city streets.

- Frank Krygowski

On Monday, November 26, 2012 7:05:07 PM UTC-5, datakoll wrote:
IS THERE A BLOOD N URINETEST ?

IIRC, it's something like 0.030 BAC to qualify for entry.

Or is that the annual keg ride? Now I forget.

- Frank Krygowski