Wheels and Gearing for Alpine Event?



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bsouche

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Nov 21, 2003
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I am doing a race in central France (Cantal region) this summer. It is 237km in length with 2.8km of total climbing. Also planning on doing some of the epic climbs of the tour and taking in a stage or two while I'm there. Looking for advise on wheels. I am 200+ lbs and an average climber. Am considering Mavic Cosmic Carbones or Kyrium SSC SL's. Like the aluminum rim for braking (versus carbon) and have used both before but never on the type of climbs I'm going to do. I realize that the Cosmics are a little heavier and more aero (obviously not a benefit in climbing) but there are quite a few rolling and flatter sections where they would be potentially beneficial. I can only bring one wheel set over. I also was leaning towards tubulars (having used them before) but am concerned about rolling them on the long decents.....is that a real concern?

Re gearing, I was considering using 53x39 chain rings with a 9spd. 12x27 cassette however am also looking at changing to an FSA compact 50x34 setup with a 9 spd. 11x23 cassette. Does the flatter gearing more than compensate for the slight reduction in bailout gear?

Appreciate thoughts/comments.

Bernie
 
N

Nick Payne

Guest
It's much better to have a low gear available that you might not need than to find that your bottom
gear is too high and there is still 10km of the climb left to go. And a gear that you can manage
comfortably on the first mountain pass of the day is not the same as the gear that you need on the
same climb when you already have 150km and couple of thousand metres of climbing in your legs.

Just last Sunday we had our annual alpine randonnee of 200km with just over 4000m of climbing. On
the last climb (which starts at the 140km point) of 18km at an average 6% gradient, I must have
passed several dozen riders who could no longer push their 39-23 or 39-25 at a cadence much above 40
or so. At least several of them still had their sense of humour, and offered me any price I wanted
for my 32t chainring...

Nick

"bsouche" <[email protected]> wrote in message
news:[email protected]...
> I am doing a race in central France (Cantal region) this summer. It is 237km in length with 2.8km
> of total climbing. Also planning on doing some of the epic climbs of the tour and taking in a
> stage or two while I'm there. Looking for advise on wheels. I am 200+ lbs and an average climber.
> Am considering Mavic Cosmic Carbones or Kyrium SSC SL's. Like the aluminum rim for braking (versus
> carbon) and have used both before but never on the type of climbs I'm going to do. I realize that
> the Cosmics are a little heavier and more aero (obviously not a benefit in climbing) but there are
> quite a few rolling and flatter sections where they would be potentially beneficial. I can only
> bring one wheel set over. I also was leaning towards tubulars (having used them before) but am
> concerned about rolling them on the long decents.....is that a real concern?
>
> Re gearing, I was considering using 53x39 chain rings with a 9spd. 12x27 cassette however am also
> looking at changing to an FSA compact 50x34 setup with a 9 spd. 11x23 cassette. Does the flatter
> gearing more than compensate for the slight reduction in bailout gear?
>
> Appreciate thoughts/comments.
>
> Bernie
>
>
>
> --
 
R

Robert Chung

Guest
bsouche wrote:
> I am doing a race in central France (Cantal region) this summer. It is 237km in length with 2.8km
> of total climbing. Also planning on doing some of the epic climbs of the tour and taking in a
> stage or two while I'm there. Looking for advise on wheels. I am 200+ lbs and an average climber.
> Am considering Mavic Cosmic Carbones or Kyrium SSC SL's. Like the aluminum rim for braking (versus
> carbon) and have used both before but never on the type of climbs I'm going to do. I realize that
> the Cosmics are a little heavier and more aero (obviously not a benefit in climbing) but there are
> quite a few rolling and flatter sections where they would be potentially beneficial. I can only
> bring one wheel set over. I also was leaning towards tubulars (having used them before) but am
> concerned about rolling them on the long decents.....is that a real concern?
>
> Re gearing, I was considering using 53x39 chain rings with a 9spd. 12x27 cassette however am also
> looking at changing to an FSA compact 50x34 setup with a 9 spd. 11x23 cassette. Does the flatter
> gearing more than compensate for the slight reduction in bailout gear?
>
> Appreciate thoughts/comments.
>
> Bernie

1. Cantal is not in the Alps, so this is not an Alpine event.
2. Le Tour is a race. L'Etape du Tour is not a race.
3. Any wheels you want to use will work, even if your going to do some other "epic" climbs later in
your visit. You may have problems finding specialty parts in smaller villages or on weekends.
4. Gearing is up to you. It worries me that you describe the course by "have used both [types of
wheels] before but never on the types of climbs I'm going to do." This is a long stage but not an
especially mountainous one -- the issue is that the two biggest climbs come late in the day. The
course doesn't boast huge grades; rather it rolls up and down, incessantly so in my opinion. By
the end of the day you may want a lowish gear. Climbs in the Alps and the Pyrenees will be worse.
By the end of your visit you may want a lowish gear.
 
R

Remove The Poli

Guest
Not only you, but 97% of cycling enthusiasts, are riding gears not even close to your optimum.

I am a sucky climber, so it especially makes me fume when master's fatties (me) and non-fatties talk
about sometimes "needing the 27" ; as if they are within 10% of Lance's climbing ability.

Look at the math.

Armstrong rides a 39x24 for Alpe d'Huez. If you watch the video of 2002 he is in that gear for real,
it's not just a precaution.

So, the best climber in the world rides a, let's call it, 39/24= ~
8/5= 1.6 gear,meaning there's one and sixth/tenth's wheel revs for each crankset rev.

So how does your power-to-weight ratio compare to Armstrongs? Say you're 200 lbs and actualy a bit
above average, which might be, say, 75% of Lance's sustained absolute power output. So let's say he
weighs ~150 and can put out, for the sake of argument, 300 watts on a long climb ( I know it's
pobably more but it's the proportions that matter here.)

( We won't even factor in that he doesn't have to carry 1) a jacket,
9) food, 3)more than one bottle water, 4) a spare tube, 5) a helmet,
10)a pump, 7) a bike that weighs more thn 15 lbs....)

We won't even factor in that there's almost no way you can put out 75% of what Lance does.

But still, then you could put out about 225 watts. So he's at
11/150= 2 watts per pound and you're at 225/200= 1.125 watts per pound.

To have the same cadence available as Lance does with his gearing, you'd want the same ratio between
your lowest gear and your watts/pound.

So, if I haven't fried the cells too much since high school algebra;

11.1:2 ~~ ?:.1.125; and ? = .9;

This means you need a gear where one revolution of the cranks gives .9 revolution of the wheel.
Something like a 30-32 or so.

Your idea of a 34-27, while closer to reality than the total fantasy of 39-27; is very far off.

To obtain a ".9" gear in this system you would need a triple or very large rear sprocket, for
instance a 50-40-30 with a 27 rear; or a 50-34 with a 32 rear.

Roberto Heras- ROBERTO HERAS!!!- rode a TRIPLE in parts of the Vuelta; I can't believe everyone
makes believe they only need a double even in the mountains. Isn't a little ridiculous to try to
ride the same gears as the best climbers in the whole freaking world?

-Signed; The Lard Muffin ; who absollutely INCHES up steep mountains on a MTB crankset 44-32-22
with 12-28.
 
P

Pete Biggs

Guest
remove the polite word to reply wrote: /snip
> To obtain a ".9" gear in this system you would need a triple or very large rear sprocket, for
> instance a 50-40-30 with a 27 rear; or a 50-34 with a 32 rear.
>
> Roberto Heras- ROBERTO HERAS!!!- rode a TRIPLE in parts of the Vuelta; I can't believe everyone
> makes believe they only need a double even in the mountains. Isn't a little ridiculous to try to
> ride the same gears as the best climbers in the whole freaking world?

Well said Muff!

~PB
 
R

Robert Chung

Guest
remove the polite word to reply wrote:
> Isn't a little ridiculous to try to ride the same gears as the best
climbers
> in the whole freaking world?

Not necessarily. It's less ridiculous, for example, than thinking that Armstrong climbed the Alpe
d'Huez at 105rpm so you should, too.
 
T

Tim McNamara

Guest
>> I am doing a race in central France (Cantal region) this summer. It is 237km in length with 2.8km
>> of total climbing. Also planning on doing some of the epic climbs of the tour and taking in a
>> stage or two while I'm there. Looking for advise on wheels. I am 200+ lbs and an average climber.
>> Am considering Mavic Cosmic Carbones or Kyrium SSC SL's.

As one 200 lb+ clydesale to another: the weight of your wheels is the least of your worries. Take
your most reliable wheels.

Two summers ago I got up many of the climbs in the Alps with a 38 x 28 and found I had plenty
of low gear.
 
T

Tim McNamara

Guest
[email protected] (remove the polite word to reply) writes:

> Not only you, but 97% of cycling enthusiasts, are riding gears not even close to your optimum.

<snip specious math and reasoning>

> I can't believe everyone makes believe they only need a double even in the mountains. Isn't a
> little ridiculous to try to ride the same gears as the best climbers in the whole freaking world?

Pro bike racers don't ride gear inches- they ride bikes in races as fast as they can. The Armstrong
example is goofy as he rides gears way lower than almost all the rest of the competition- much like
Charly Gaul did 50 years ago, in fact. Even the competition doesn't emulate him, why should non-
racers worry about it? Amateurs such as the OP and myself are going to be going half as fast as
Armstrong up the Alps- I wouldn't even be going as fast as Cipollini up the Alps, to be honest. Alpe-
d'Huez took me 1:18, IIRC, long enough for Armstrong or Pantani to climb it twice.

Unless you're winching 60 lbs of camping gear up l'Alpe-d'Huez, there's no need for a reasonably fit
rider to have to resort to a granny gear to get up it unless they're compensating for some sort of
problem like bad knees. IMHO there's no reason to make riding the Alps seem like it's more of a
tribulation or more heroic than it is. Alpe-d'Huez is a lovely climb in its own right, with dramatic
views of Bourg-d'Oisans and the Romanche valley. And if you go, don't miss the D211a branching off
the road up Alpe-d'Huez at (IIRC) La Grave.
 
T

Tim McNamara

Guest
"Robert Chung" <[email protected]> writes:

> remove the polite word to reply wrote:
>
>> Isn't a little ridiculous to try to ride the same gears as the best climbers in the whole
>> freaking world?
>
> Not necessarily. It's less ridiculous, for example, than thinking that Armstrong climbed the Alpe
> d'Huez at 105rpm so you should, too.

Exactly. I got up l'Aple-d'Huez in a 38 x 28 with no problem (at half Armstrong's speed and probably
a little less than half of his cadence).
 
P

Pete Biggs

Guest
Robert Chung wrote:
> remove the polite word to reply wrote:
>> Isn't a little ridiculous to try to ride the same gears as the best climbers in the whole
>> freaking world?
>
> Not necessarily. It's less ridiculous, for example, than thinking that Armstrong climbed the Alpe
> d'Huez at 105rpm so you should, too.

I don't think so (and it doesn't have to be 105 anyway, just reasonably quick). A relatively weak
rider can use a high cadence to very good effect, too. Just at lower speed with lower gears. That's
got to be better than mashing too large a gear that you can't get up to 40rpm, let alone 90, let
alone 105. And you can always go slower if the gear is too low, you can't always go fast enough if
it's too high.

~PB
 
P

Phillip Stevens

Guest
My two cents is to use a triple chainset or at least a compact chainset.

I've done many German, Austrian and Italian alpine Radmarathons, and finished some of them well
enough to be invited back into the A start group the following year, always on a triple 105
groupset. These events are typically around 200km and 2,000m to 4,000m climbing.

I find that having the 30 or 34 tooth chainring and a tighter cassette (eg, 11-21, 12-23, 12-25)
gives you many more options whilst climbing. Obviously, climbs are never the same gradient. They
might be a little steeper in the serpentine, and flatter between. If you've got more gear choice
because of the tighter cassette, you can be faster overall. Others will be stuck in 39x27 and have
to compensate for slight variations through cadence. You'll have the choice of 30x21 or 30x23 or
30x19 or 30x25 all around the same length, and what's more the tight cassette changes much better
under load. For me the most relevant part is the cassette between 14-17. I prefer to have
14,15,16,17 and a 29 chainring all packed for climbing...

Living in a very mountainous city until recently I dropped the 53 chainring all together, and used
the most relevant solution 44&29 on a 2x9 mountain crankset.

BTW. I have Mavic SSC SL's, too. I like 'em, but then they're just trendy at the moment... Its the
legs that make you go uphill in the end.

Phillip FIXXED on 43x16

"bsouche" <[email protected]> wrote in message
news:[email protected]...
> I am doing a race in central France (Cantal region) this summer. It is 237km in length with 2.8km
> of total climbing. Also planning on doing some of the epic climbs of the tour and taking in a
> stage or two while I'm there. Looking for advise on wheels. I am 200+ lbs and an average climber.
> Am considering Mavic Cosmic Carbones or Kyrium SSC SL's. Like the aluminum rim for braking (versus
> carbon) and have used both before but never on the type of climbs I'm going to do. I realize that
> the Cosmics are a little heavier and more aero (obviously not a benefit in climbing) but there are
> quite a few rolling and flatter sections where they would be potentially beneficial. I can only
> bring one wheel set over. I also was leaning towards tubulars (having used them before) but am
> concerned about rolling them on the long decents.....is that a real concern?
>
> Re gearing, I was considering using 53x39 chain rings with a 9spd. 12x27 cassette however am also
> looking at changing to an FSA compact 50x34 setup with a 9 spd. 11x23 cassette. Does the flatter
> gearing more than compensate for the slight reduction in bailout gear?
>
> Appreciate thoughts/comments.
>
> Bernie
>
>
>
> --
 
R

Robert Chung

Guest
Pete Biggs wrote:
> That's got to be better than mashing too large a gear that you can't get up to 40rpm, let alone
> 90, let alone 105.

> And you can always go slower if the gear is too low, you can't always go fast enough if it's
> too high.

If you can't get up a particular hill in a given gear ratio at 40rpm, why would you think it'd be
better to spin *faster*?
 
T

Tim McNamara

Guest
"Robert Chung" <[email protected]> writes:

> Pete Biggs wrote:
>
>> That's got to be better than mashing too large a gear that you can't get up to 40rpm, let alone
>> 90, let alone 105.
>
>> And you can always go slower if the gear is too low, you can't always go fast enough if it's
>> too high.
>
> If you can't get up a particular hill in a given gear ratio at 40rpm, why would you think it'd be
> better to spin *faster*?

To toss in my $0.02, I think that re: climbing fitness is far more important than gears. Be prepared
for what you're going to do.
 
N

Nick Payne

Guest
Try going up it as the last of several long climbs, or try going up it three or four times in
succession, and see how your 38x28 feels...

Nick

"Tim McNamara" <[email protected]> wrote in message news:[email protected]...
>
> Exactly. I got up l'Aple-d'Huez in a 38 x 28 with no problem (at half Armstrong's speed and
> probably a little less than half of his cadence).
 
B

Bruce Frech

Guest
On a typical 8% grade, with a mass of 85 kg and a gear of 38x28 then 200 watts gives you a speed of
about 3 m/s, and a cadence of just over 60rpm. From my years of touring the Alps I prefer a 38x34 so
when I get those extended 10%+ climbs I can still sit and spin @ 60rpm. The only changes I make to
my regular road bike for touring is switch to a 12-34 to go with the 50-38, and put a mtbike rear
derr to handle the 34 cog.

go to http://www.analyticcycling.com/ForcesSpeed_Page.html for more computations.

Bruce

"Nick Payne" <[email protected]> wrote in message news:[email protected]...
> Try going up it as the last of several long climbs, or try going up it
three
> or four times in succession, and see how your 38x28 feels...
>
> Nick
>
> "Tim McNamara" <[email protected]> wrote in message news:[email protected]...
> >
> > Exactly. I got up l'Aple-d'Huez in a 38 x 28 with no problem (at half Armstrong's speed and
> > probably a little less than half of his cadence).
 
P

Pete Biggs

Guest
Robert Chung wrote:

>> better than mashing too large a gear that you can't get up to 40rpm, let alone 90, let alone 105.
>
>> And you can always go slower if the gear is too low, you can't always go fast enough if it's
>> too high.
>
> If you can't get up a particular hill in a given gear ratio at 40rpm, why would you think it'd be
> better to spin *faster*?

Because it's more efficient, less punishing and more enjoyable to pedal at one's optimum cadence -
but of course the gear would have to be lower in order to be able to spin faster.

~PB
 
R

Robert Chung

Guest
Pete Biggs wrote:
> Robert Chung wrote:
>
>>> better than mashing too large a gear that you can't get up to 40rpm, let alone 90, let
>>> alone 105.
>>
>>> And you can always go slower if the gear is too low, you can't always go fast enough if it's
>>> too high.
>>
>> If you can't get up a particular hill in a given gear ratio at 40rpm, why would you think it'd be
>> better to spin *faster*?
>
> Because it's more efficient, less punishing and more enjoyable to pedal at one's optimum cadence -
> but of course the gear would have to be lower in order to be able to spin faster.

What gives you the idea that it's more efficient and less punishing (I leave out enjoyable, which is
a matter of taste) to pedal at one's "optimum" cadence? How do you know what your optimum is?

To go back upthread, "remove the polite word" suggested that it was "ridiculous to try to ride the
same gears as" pros. My response was, and continues to be, "not necessarily." That doesn't mean that
no climb exists where one wouldn't wish lower gears -- it means it's not necessarily ridiculous.
 
R

Rik O'Shea

Guest
[email protected] (remove the polite word to reply) wrote in message news:<[email protected]>...
> Not only you, but 97% of cycling enthusiasts, are riding gears not even close to your optimum.
>
> I am a sucky climber, so it especially makes me fume when master's fatties (me) and non-fatties
> talk about sometimes "needing the 27" ; as if they are within 10% of Lance's climbing ability.
>
> Look at the math.
>

Below are my calculations for Armstrongs 2001 Alpe D'Huez climb. He averaged ~460W and had a average
gear of 39 x 21. For the 10% sections he would have used a 39 x 24. Now if you weight 200lb and have
a 23 lb bike and wish to climb at at least 65 rpm (assuming 220W output) you need a 39x34 or 32x28.
For the steep 10% sections if you lower your cadence to ~55 the 32x28 is still good enough.

So if you are 200lb and of average fitness (220W output) and want to climb Alpe D'Huez relatively
comfortably at ~65 cadence you should use a triple. The 14.2 km climb should take you ~1hr 31 min at
an average of 9.3 km/h.

*** "Armstrong Alpe D'Huez" ***

Input Parameters
----------------
Cyclist Velocity [km/h] ................ 22.411 Distance [km] .......................... 14.200 Hill
Slope (%) ......................... 7.69 Cyclist Mass [kg] ...................... 71.00 Cyclist
Height [cm] .................... 180.35 Cyclist Gender ......................... Male Cd
(Coefficient of Drag) ............... 0.95 Wheel Diameter [cm] .................... 66.72 Wheel
Circumference [cm] ............... 209.60 Bicycle Mass [kg] ...................... 8.50 Air Density
[kg/m^3] ................... 1.225 Crr (Coefficient of Rolling Resistance) 0.0065 Bicycle
Transmission Efficiency ........ 0.980 Cadence (RPM) .......................... 90 Chainring Size
......................... 39

Derived Parameters
------------------
Vector Velocity [km/h] ................. 22.411 Vector Velocity [m/s] .................. 6.225 Gear
Development [m] ................... 4.150 Gear Size [inch] ....................... 52.01 Gear Ratio
............................. 39X19.70 Cyclist Body Surface Area [m^2] ........ 1.900 Cyclist
Frontal Area [m^2)] ............ 0.3421 CdA [m^2] .............................. 0.3250

Results
-------
Time [hour:min:sec] .................... 0:38:1 Time [sec:hundred] ..................... 2281.023

Power Total [W] ........................ 462.2 Power Air Resistance [W] ............... 48.0 10.39%
Power Rolling Resistance [W] ........... 31.6 6.83% Power Drive Train [W] .................. 9.2
2.00% Power Hill [W] ......................... 373.4 80.78%

Power Total [hp] ....................... 0.620 Power/mass ratio [W/kg] ................ 6.510
Power/CdA ratio [W/m^2] ................ 1422.25

Total Cal/hr ........................... 1596 Basal Cal/hr ........................... 67 Work
Cal/hr ............................ 1529

Total Calories ......................... 1011 Basal Calories ......................... 42 Work
Calories .......................... 969
 
D

Dvt

Guest
Rik O'Shea wrote:
> Below are my calculations for Armstrongs 2001 Alpe D'Huez climb.

[snip]

> Power Total [W] ........................ 462.2 Power Air Resistance [W] ............... 48.0
> 10.39% Power Rolling Resistance [W] ........... 31.6 6.83% Power Drive Train [W]
> .................. 9.2 2.00% Power Hill [W] ......................... 373.4 80.78%

That's an interesting stat. One of the worst hills that any of us will climb demonstrates about 19%
energy loss to factors other than simply lugging our carcass up the hill. I'm not sure of the
appropriate conclusion to this data, but it is very interesting data.

Dave dvt at psu dot edu
 
D

David Damerell

Guest
Tim McNamara <[email protected]> wrote:
>To toss in my $0.02, I think that re: climbing fitness is far more important than gears. Be
>prepared for what you're going to do.

This is, of course, true, but if you're going up the hill tomorrow you can buy a granny ring
today. :)

[Literally true in my case - I've got a 74mm BCD just waiting to be used; pop on the ring, adjust
the limit screw, slack off a little of the fder cable, and away I go.]
--
David Damerell <[email protected]> flcl?
 
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