# diff in top speed between 11 and 12 teeth?



## j3fri (Dec 31, 2006)

hi guys,i am curious wad would be the diff in top speed between 11 and 12 teeth if u're using 53...

lets say imagine that i got the power and its a flat course with no strong winds.. thx...


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## iliveonnitro (Feb 19, 2006)

53x12
Cadence, Speed:
70 rpm, 21.41mph
80 rpm, 27.89mph
90 rpm, 31.38mph
100rpm, 34.87mph

53x11
70 rpm, 26.63mph
80 rpm, 30.43mph
90 rpm, 34.23mph
100rpm. 38.04mph

http://analyticcycling.com/GearSpeedCadence_Page.html

*edit* it doesn't matter what the wind or terrain is like. If you are at a certain cadence in a certain gear, you will go that speed.


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## j3fri (Dec 31, 2006)

thx a lot..


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## Kalrog (Aug 17, 2006)

iliveonnitro said:


> http://analyticcycling.com/GearSpeedCadence_Page.html
> 
> *edit* it doesn't matter what the wind or terrain is like. If you are at a certain cadence in a certain gear, you will go that speed.


The question is really "Can you really push 100+RPM in 53x11?" If so, then by all means get the 11. If not (like most of us) tuck when you go down hill and rest.


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## StillRiding (Sep 16, 2006)

j3fri said:


> hi guys,i am curious wad would be the diff in top speed between 11 and 12 teeth if u're using 53...
> 
> lets say imagine that i got the power and its a flat course with no strong winds.. thx...


According to Dr. Coggan, co-author of "Training & Racing with a Power Meter", most people will develop their maximum power at a cadence between 110 and 135. If you assume that a typical Cat 4 racer can sustain about 700 watts for a 30 to 45 second sprint, then typical top sprint speeds on the flat in no wind should be about 35-40 mph. At 120 RPM, a 53-12 would give 41.4 mph and a 53-11 would give 45.2 mph, so unless you're sprinting down wind or down hill, either gear would be sufficient and the 53-12 might give better acceleration.


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## flyboy50 (Mar 13, 2007)

Damn, I hate being a junior. :mad2: Stuck with a 52-14, even if you're the only junior in a mixed category. :cryin:


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## Fixed (May 12, 2005)

*excel*

http://www.midcalracing.com/gears.xls


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## terzo rene (Mar 23, 2002)

Unless you are spinning out in the 12 the 11 will be slower. It won't change the power you can generate and since there would be minutely more drivetrain friction with the 11 you would actually go slower.


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## j3fri (Dec 31, 2006)

oh i see.. thx.. i am using 25-12 now,got another spare cassette 23-11,but i need the 25 teeth to go uphill... i training to sprint,so i was just wondering the diff in top speed in 12 and 11... maybe lets say downhill then i might need 11 but on flats,so far 12 satisfy me.. my top speed is rather slow currently.. 57.5km/h with no lead out.. usually i sprint from cruising speed of 40km/h...


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## Sweet Milk (Oct 13, 2004)

You cruise solo at 40 km/h (25 MpH) and for climbing need a 25? Either you have some damn steep and long hills, or you are a spinner. In the first case it would make sense to have an 11, for downhills, not sprints. In the latter case it makes no sense to have an 11, since you will do better in a sprint with a 12 or even 13.

It is not so much whether you spin out in the twelve that determines the difference, but rather which gear allows you to get closer to your optimal cadence for max. power output. For most strong sprinters that is a 53/12. I can only think of a very few that would benefit from an 11, that is more of a high speed down hill gear.

I live in a hilly area and have recently switched to a compact crank (50-34) and 11-26 casette; I like this a lot.


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## Mark McM (Jun 18, 2005)

j3fri said:


> hi guys,i am curious wad would be the diff in top speed between 11 and 12 teeth if u're using 53...


The answer to that question is the same as the answer to this question:

Q: Which is faster, a red bike and blue bike?
A: The one with the more powerful rider.

Top speed is primarily determined by power output, not be small variations between gear ratios. Since very few riders will be "spun-out" in a 53-12 (which is 41 mph at 120 rpm), there are very few riders who will go faster with a 53-11 at the same power output. In fact, if your top speed is slower than 40 mph or so, you'll probably go slower in the 53-11, because you'll be below your maximum power cadence range. Since my top end speed on flat ground in windless conditions is a meager 35 mph or so, I'm actually faster in a 53-13 than a 53-12.


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## msohio (Feb 23, 2004)

*What About Descending*

I think the biggest reason to go for the 11 is to be able to generate additional speed when descending. Can't max out an 11 on the flat but the additional speed on a gradual descent is worth something IMO. I find I can pedal my way to a faster speed with the 11 on modest descent (one that will spin out the 12) than I can by getting into a tuck and lettin' it roll.


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## den bakker (Nov 13, 2004)

flyboy50 said:


> Damn, I hate being a junior. :mad2: Stuck with a 52-14, even if you're the only junior in a mixed category. :cryin:


huh? you have not raced your first race yet and you know this is an issue?


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## photosbyjt (Apr 7, 2007)

flyboy50 said:


> Damn, I hate being a junior. :mad2: Stuck with a 52-14, even if you're the only junior in a mixed category. :cryin:


Race as a senior. When I was a junior I did both senior and junior races. I hated the gear restrictions, so I did a lot of senior races. Lots to be gained by going that route.


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## den bakker (Nov 13, 2004)

photosbyjt said:


> Race as a senior. When I was a junior I did both senior and junior races. I hated the gear restrictions, so I did a lot of senior races. Lots to be gained by going that route.


Per USCF rules, a person who is a junior as determined by age has to race with junior gearing no matter if he/she rides in the junior catagory or Pro/1/2.


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## photosbyjt (Apr 7, 2007)

den bakker said:


> Per USCF rules, a person who is a junior as determined by age has to race with junior gearing no matter if he/she rides in the junior catagory or Pro/1/2.


Must be a newer rule ( I haven't been a junior since 1990) or I was a rule breaker and never got caught.


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## llvllatt (Jul 23, 2005)

I believe it's a new rule for this year

Does anyone know if it applies to Canadian Juniors racing in the states? Cat 1/2 at Enumclaw's gonna be crazy if I'm stuck spinning my 52-14


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## Gnarly 928 (Nov 19, 2005)

If there is a long descent in a race course, I like using an 11. Is it faster? Probably not, except in special circumstances. 

But, I can sometimes get away on descents if most everyone else is on 12s. I can 'scare' the others, too, with accelerations when they expect everyone to keep all tucked in in a nice line...Then, they have to spin up to catch up, while I can turn a more sane cadence.. I try to keep my legs warm while descending..which I do by turning that big gear but at a slower cadence, so I still get a recovery and yet still add some (small net amount of) drive...

I ride lots of long steep climbs..Descending, I can often spin out in a 12/53. Just yesterday we were riding part of last year's Mt Hood Classic course and on my 12/23, with a big fast bunch of riders going down a long descent...I went off the back because I was spun out on my 12..(and I was weak and almost blown by the prior ascent). I was wanting that 11, so I could loaf along in the pack,(I'm "allowed", being a senior citizen now) which was hammering along at my max RPM for probably 12-15 miles.. Cooper Spur at 4000+ back down to Hood River at 50', with a bunch of strong guys showing off.. Just a few miles of sitting in (on the 11) as opposed to the whole ride downhill totally spun out (for me) probably would have let me stick, though we started down with about 13 and only about 5 were there at the end..

The difference (a 12 vs an 11) leaves me with a 'hole' in my climbing gears..but I can work around that..If I am not racing, a 12 is my gear of choice, but an 11 works well for me when I want to go fast as possible, given the terrain and wind I usually ride. put er in overdrive...

Don Hanson


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## Mark McM (Jun 18, 2005)

*Cadence, speed and tucking*



msohio said:


> I think the biggest reason to go for the 11 is to be able to generate additional speed when descending. Can't max out an 11 on the flat but the additional speed on a gradual descent is worth something IMO. I find I can pedal my way to a faster speed with the 11 on modest descent (one that will spin out the 12) than I can by getting into a tuck and lettin' it roll.


I guess that depends on the cadence that you are "spun out" and the speed where it is faster to 'tuck and coast' vs. pedaling. For me, tucking and coasting is faster (at least for extended distances) at least by 40 mph. In a 53/12, my cadence at 40 mph is 116, which for me is not yet spun-out. In fact, I usually have only a 13 tooth small sprocket on my cassette, and even that rarely limits my speed on a downhill (I've been known to accelerate to jump onto the wheel of someone who has just passed me on a downhill at 45 mph while using only a 53/13).


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## Kestreljr (Jan 10, 2007)

When I have my 12 on, I spin out around 54mph. When I have my 11 on, I spin out at about 61mph... but most of that is up hill. I am actually putting on two 11 tooth cogs on my next cassette- this should keep my average speed up on my rides.

:wink:


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## bill (Feb 5, 2004)

Gnarly 928 said:


> If there is a long descent in a race course, I like using an 11. Is it faster? Probably not, except in special circumstances.
> 
> But, I can sometimes get away on descents if most everyone else is on 12s. I can 'scare' the others, too, with accelerations when they expect everyone to keep all tucked in in a nice line...Then, they have to spin up to catch up, while I can turn a more sane cadence.. I try to keep my legs warm while descending..which I do by turning that big gear but at a slower cadence, so I still get a recovery and yet still add some (small net amount of) drive...
> 
> ...


I don't know, man. I did a race a few weeks ago where we were hitting speeds of 50 on the descents -- I realize that this is an everyday occurrence for some, but not for me -- and I don't ever remember spinning out my 12. I was mostly tucked, and keeping up just fine (the issue was the balls not to slow on the twists, not spinning out). I certainly don't remember looking for another gear.
I actually don't think that anyone much needs an 11. Like, anyone. I was talking to the guys from Jelly Belly -- a couple of their sprinters use an 11 sometimes, but mostly they use 12-25 or 12-23.


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## asgelle (Apr 21, 2003)

bill said:


> I don't know, man. I did a race a few weeks ago where we were hitting speeds of 50 on the descents -- I realize that this is an everyday occurrence for some, but not for me -- and I don't ever remember spinning out my 12. I was mostly tucked, and keeping up just fine (the issue was the balls not to slow on the twists, not spinning out). I certainly don't remember looking for another gear.


What if you had come off the back just before the top and had to chase back on?


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## bill (Feb 5, 2004)

asgelle said:


> What if you had come off the back just before the top and had to chase back on?


Well, if I'm not going downhill, I am not going to hit 40 in any gear. I'm just not, and I doubt that many are. At speeds over 40 on a downhill, I just don't think that I'm going to push it much harder in any gear. I don't have an analysis for this, but the major forces have to be wind resistance and gravity, right? And, I'm either going to push it just a very, very little, which I can do at a high cadence, or I'm not going to push it at all. Most likely, I think, not at all.
I've looked for the right gear in a race -- bad bad sign that, the inability to find the right gear -- but I don't remember ever looking for an 11.


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## Kerry Irons (Feb 25, 2002)

*Understanding aerodynamics*



asgelle said:


> What if you had come off the back just before the top and had to chase back on?


What people seem to be missing here is that when you are in a tight tuck, your aerodynamic drag is MUCH lower than when you are "up and pedaling." This is the reason you can coast as fast as someone pedaling. In fact, I commonly PASS people who are pedaling down hill (as I coast,) and I am getting a rest for my legs while they are still working. Are there extreme situations where you might use an 11? Yes, in a downhill race finish. Put your 11 on for that situation. Otherwise, . . . .


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## ElvisMerckx (Oct 11, 2002)

flyboy50 said:


> Damn, I hate being a junior. :mad2: Stuck with a 52-14, even if you're the only junior in a mixed category. :cryin:


When I raced as a juniors in the mid-late 80s, we had a 52x15 gear restriction. The only time I ever complained about being undergeared was when I finished 3rd in a Senior Cat 2-3 finishing sprint. In all honesty, I probably wouldn't have won it with a bigger gear, but it was a convincing excuse at the time.

If you learn how to spin properly, you're never going to need anything more than that 14 in junior races.


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## asgelle (Apr 21, 2003)

Kerry Irons said:


> What people seem to be missing here is that when you are in a tight tuck, your aerodynamic drag is MUCH lower than when you are "up and pedaling." This is the reason you can coast as fast as someone pedaling. In fact, I commonly PASS people who are pedaling down hill (as I coast,) and I am getting a rest for my legs while they are still working. Are there extreme situations where you might use an 11? Yes, in a downhill race finish. Put your 11 on for that situation. Otherwise, . . . .


Lets put some numbers to that. Using the defaults at analyticcycling.com except for a 7% downhill. A rider putting out a modest 200 W could increase his drag by 20% and still be faster than the rider just coasting.


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## Kerry Irons (Feb 25, 2002)

*More numbers*



asgelle said:


> Lets put some numbers to that. Using the defaults at analyticcycling.com except for a 7% downhill. A rider putting out a modest 200 W could increase his drag by 20% and still be faster than the rider just coasting.


And at that slope and speed (40 mph), 20% more power would get you only 0.7 mph. The drag reduction of going to a decent (not great) aero wheel would give you the same speed increase. Setting your cranks horizontal, knees on the top tube, and chin near to the stem (a tight tuck) will give you more speed increase than that.


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## Mark McM (Jun 18, 2005)

*Analytic Cycling results*



asgelle said:


> Lets put some numbers to that. Using the defaults at analyticcycling.com except for a 7% downhill. A rider putting out a modest 200 W could increase his drag by 20% and still be faster than the rider just coasting.


Are you sure you modelled that right? I went to the Analytic Cycling web page for 'Speed given Power' (http://www.analyticcycling.com/ForcesSpeed_Page.html). I used the default values, but changed the grade to -0.07 (7% downhill) and changed the power to 200 Watts. The resulting speed was 19.58 m/s (43.8 mph). I then set the power to 0 (coasting) and reduced the frontal area by 20% (tight tuck), and ran the simulation again. The resulting speed was 19.90 m/s (44.5 mph), or 0.7 mph faster by coasting and tucking.

In my own experience, sometimes a will go into a tight coasting tuck while other riders continue to pedal down grades similar to the simulation above. If the pedaler pedals hard (above their A.T., probably closer to 300+ Watts), they will slowly pull away from me. But after a minute or so, after they tire of pedaling at this high power and begin to coast, I quickly catch them and pass them. By the bottom of the hill, I'll be a few hundred yards ahead and fully rested, while the other rider is behind me and still recovering from his earlier pedaling effort.


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## asgelle (Apr 21, 2003)

Mark McM said:


> Are you sure you modelled that right? I went to the Analytic Cycling web page for 'Speed given Power' (http://www.analyticcycling.com/ForcesSpeed_Page.html). I used the default values, but changed the grade to -0.07 (7% downhill) and changed the power to 200 Watts. The resulting speed was 19.58 m/s (43.8 mph). I then set the power to 0 (coasting) and reduced the frontal area by 20% (tight tuck), and ran the simulation again. The resulting speed was 19.90 m/s (44.5 mph), or 0.7 mph faster by coasting and tucking.


I did it a little differently following Kerry's statement, "What people seem to be missing here is that when you are in a tight tuck, your aerodynamic drag is MUCH lower than when you are "up and pedaling." This is the reason you can coast as fast as someone pedaling."

I took the analyticcycling defaults (CdA=0.25) and 0 W for the person coasting. That gave speed 17.8 m/s. I then considered someone pedaling at 200 W and looked at how much of a drag penalty it would take to break even. It worked out that increasing CdA to 0.3 (25% increase) at 200 W also gave 17.8 m/s. At any lower drag, the person pedaling would be faster.

That tells me that starting from a tight tuck, I can afford to sit up and sacrifice a fair amount of aero to put some power to the pedals. I'm not thinking of sitting up high hands on the tops. I'm thinking crouched down hands in drops reaching a good balance between power sacrificing position and position sacrificing power.

I should add that I have no idea of the relative drag between someone coasting chin on stem, feet at 9 and 3 o'clock and hands in by chin and someone pedaling hands on drops, shoulders down, and head tucked in.


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## Kerry Irons (Feb 25, 2002)

*Personal experience*



asgelle said:


> I should add that I have no idea of the relative drag between someone coasting chin on stem, feet at 9 and 3 o'clock and hands in by chin and someone pedaling hands on drops, shoulders down, and head tucked in.


And this is the key point. My experience is the same as Mark McM's. I can follow anybody down a hill in a tuck while they pedal. At 35 mph and above, I'm going to guess that the tight tuck is worth 2 mph compared to "crouched in the drops" and pedaling. I can consistently coast past people who are pedaling, and I'm getting a rest.


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## tobu (Dec 19, 2004)

Speaking from personal experience (and I don't care what analytical cycling says) there are many situations where tucking is much slower than pedaling on a hill, especially when the gradients are moderate to fairly steep. At some point, I think everybody coasts/ tucks, but on extended non-technical descents of moderate gradients the riders who are pedaling will pull away. This is especially pronounced when the pedalers are in a group and you are alone (and more so if the solo rider is fairly light).

Many riders have no use for an 11, but there are also many riders who use them effectively in the right situation. I've been in many situations where I would have been dropped if I didn't have an 11, or I wouldn't have done as well in a sprint without the 11. Many riders have no use for the 11, but it's completely wrong to claim that all situations can be ridden in a 12 by spinning faster.


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## Mark McM (Jun 18, 2005)

tobu said:


> Many riders have no use for an 11, but there are also many riders who use them effectively in the right situation. I've been in many situations where I would have been dropped if I didn't have an 11, or I wouldn't have done as well in a sprint without the 11. Many riders have no use for the 11, but it's completely wrong to claim that all situations can be ridden in a 12 by spinning faster.


Am I just not riding with the right riders? I regular ride and race with cat. 2 and 3 racers, and I'm never dropped on the downhills (in fact, I often use downhills to make up the ground I lost on the uphills). I never use an 11, and rarely use a 12. Granted, I'll never win a downhill sprint (or even a flat or uphill one), but I have never been in a position where a 12 wasn't enough (and usually a 13 is a enough).


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## Kestreljr (Jan 10, 2007)

Mark McM said:


> Am I just not riding with the right riders?



I say yes. Come bike with my team, we average 38mph with times in the low 60's. 12 toothers are pansies.





??Where is this the lounje?


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## asgelle (Apr 21, 2003)

Mark McM said:


> Am I just not riding with the right riders?


I'd say more likely not the right hills. I do a lot of races in the mountains and there are exactly two cases where I need an 11. One was the back side of Gates Pass to catch back on after climbing the 15% grade and always being dropped (they no longer use this course). The other is at Tour of the Gila to catch a group going down the Sapillo before the Mimbres Valley. Obviously, I don't know every hill and race course in the country, but since the cases where I need an 11 are so specialized, I can easily understand how other people have never seen the need. After all if I were a better climber, I wouldn't need it either. On the other hand, all that doesn't negate my experiences where I do need it.


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## bill (Feb 5, 2004)

asgelle said:


> I'd say more likely not the right hills. I do a lot of races in the mountains and there are exactly two cases where I need an 11. One was the back side of Gates Pass to catch back on after climbing the 15% grade and always being dropped (they no longer use this course). The other is at Tour of the Gila to catch a group going down the Sapillo before the Mimbres Valley. Obviously, I don't know every hill and race course in the country, but since the cases where I need an 11 are so specialized, I can easily understand how other people have never seen the need. After all if I were a better climber, I wouldn't need it either. On the other hand, all that doesn't negate my experiences where I do need it.


with all due respect, you felt as if your 11 was helpful twice in your life, in races the likes of most of us will never do, and . . . what am I supposed to get from this?
if you're a pro rider or a 1 or whatever, do what you do and you don't have any reason to listen to the likes of us mere mortals. I got it. but you have to qualify what you're saying, which I see that you did, finally, but not until now.
I still say that the physics are against you. Yeah, you felt as if the gearing helped you, but we don't know what would have happened had you tucked, do we?


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## asgelle (Apr 21, 2003)

bill said:


> with all due respect, you felt as if your 11 was helpful twice in your life, in races the likes of most of us will never do, and . . . what am I supposed to get from this?
> if you're a pro rider or a 1 or whatever, do what you do and you don't have any reason to listen to the likes of us mere mortals. I got it. but you have to qualify what you're saying, which I see that you did, finally, but not until now.
> I still say that the physics are against you. Yeah, you felt as if the gearing helped you, but we don't know what would have happened had you tucked, do we?


To take the last question first, you don't know what would have happened If I had tucked, but I do. I tried it (I like resting in a race as much as anyone) and I saw the pack moving away. Which makes perfect sense since they were also in a tuck and slingshotting around each other through the draft. Second, what you're supposed to take from my experiences (2 races a year, not in my life) is that equipment should match the demands of the event and no one should generalize from one set of rides and races to all.

But really, I don't see how this is a "qualification" of what I wrote earlier. I wanted to put some numbers behind the comparison of pedaling vs. coasting; I drew no conclusions. I've seen nothing to put those results in question.


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## bill (Feb 5, 2004)

asgelle said:


> To take the last question first, you don't know what would have happened If I had tucked, but I do. I tried it (I like resting in a race as much as anyone) and I saw the pack moving away. Which makes perfect sense since they were also in a tuck and slingshotting around each other through the draft. Second, what you're supposed to take from my experiences (2 races a year, not in my life) is that equipment should match the demands of the event and no one should generalize from one set of rides and races to all.
> 
> But really, I don't see how this is a "qualification" of what I wrote earlier. I wanted to put some numbers behind the comparison of pedaling vs. coasting; I drew no conclusions. I've seen nothing to put those results in question.


the point is that if you are powerful enough and skilled enough to push major wattage without compromising your aerodynamics, well, have a ball because you're better than the vast majority of us. There is a reason that 11's are made and used, I suppose, just as there are those who are so very very proficient to know when to use them. If Tom Boonen uses an 11, and I have no reason to think that he does or doesn't, I'm not going to argue with him. But his experience has absolutely no relevance to mine.
Equipment should match the demands of the event. Sho nuff. But what the event demands includes the rider. As a guy who is reasonably competitive in Cat 3/4, Masters racing, I will not encounter the event where I might need an 11. I am very confident of this. And those of my peers who think they otherwise, for them or for me, I believe are kidding themselves. And you didn't help, because you are not my peer, although you sort of pretended that you were.


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## asgelle (Apr 21, 2003)

bill said:


> the point is that if you are powerful enough and skilled enough to push major wattage without compromising your aerodynamics, well, have a ball because you're better than the vast majority of us.


I'd say it would seem that a fairly modest wattage (200 W) is enough to overcome a fairly significant break in position (20% increase in drag). Of course, you don't bother to say what you mean by "major wattage" or "compromising your aerodynamics" so for all I know we could be in complete agreement.



bill said:


> And you didn't help, because you are not my peer, although you sort of pretended that you were.


I don't know where you could have gotten that from what I wrote, but believe me, claiming you as a peer is the last thing on my mind.


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## bill (Feb 5, 2004)

> I don't know where you could have gotten that from what I wrote, but believe me, claiming you as a peer is the last thing on my mind.


well aren't you sweet.

I feel as if I know you already and we've never even met.


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## iliveonnitro (Feb 19, 2006)

I use an 11 because of my 50T front chainring (semi-compact, not quite a 53T compact).

But you guys are way over analyzing this. If someone passes you on a downhill, here's the science: start pedaling really hard. What gear? Who the hell cares; you're gonna need to be putting down a lot of power anyways and I'm sure you can spin the extra 10rpm if you need to.


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## bill (Feb 5, 2004)

Mark McM said:


> Are you sure you modelled that right? I went to the Analytic Cycling web page for 'Speed given Power' (http://www.analyticcycling.com/ForcesSpeed_Page.html). I used the default values, but changed the grade to -0.07 (7% downhill) and changed the power to 200 Watts. The resulting speed was 19.58 m/s (43.8 mph). I then set the power to 0 (coasting) and reduced the frontal area by 20% (tight tuck), and ran the simulation again. The resulting speed was 19.90 m/s (44.5 mph), or 0.7 mph faster by coasting and tucking.
> 
> In my own experience, sometimes a will go into a tight coasting tuck while other riders continue to pedal down grades similar to the simulation above. If the pedaler pedals hard (above their A.T., probably closer to 300+ Watts), they will slowly pull away from me. But after a minute or so, after they tire of pedaling at this high power and begin to coast, I quickly catch them and pass them. By the bottom of the hill, I'll be a few hundred yards ahead and fully rested, while the other rider is behind me and still recovering from his earlier pedaling effort.


I don't know what asgelle did, but this looks right to me.
down a 7% grade, tight tuck, it's faster to coast than to put out 200 W.


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## bill (Feb 5, 2004)

bill said:


> I don't know what asgelle did, but this looks right to me.
> down a 7% grade, tight tuck, it's faster to coast than to put out 200 W.


and at 300 W, you're beating the coasting guy by .3 m/sec (I guess about .7 mph, right?)


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## tobu (Dec 19, 2004)

Look, a tight tuck usually doesn't reduce the frontal area compared to a rider who is driving it on a descent. It might be fatiguing, but a pedaler will almost always beat a coaster.

Sometimes people race the descents. In those cases, the coaster will get dropped. At high speeds, sometimes an 11 is useful. End of story.


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## rruff (Feb 28, 2006)

bill said:


> I don't know what asgelle did, but this looks right to me.
> down a 7% grade, tight tuck, it's faster to coast than to put out 200 W.


I'm guessing asgelle was probably around 500W+- if he was chasing to get back on the pack. Also, that descent (and a lot of others) has some sharp turns followed by long straightish sections, where sprinting up to top speed is necessary. Racers have need of big gears in some situations. Me? I'm happy with a 48/12....


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## Mark McM (Jun 18, 2005)

tobu said:


> Look, a tight tuck usually doesn't reduce the frontal area compared to a rider who is driving it on a descent.


???

Maybe you just don't tuck tight enough. My tuck usually consists of:

- Cranks horizontal
- Knees against top tube
- Hands near stem
- elbows against top tube
- chin hovering above stem

This produces a frontal area substantially smaller than when pedaling (even when in the drops).



tobu said:


> It might be fatiguing, but a pedaler will almost always beat a coaster.


Not if its steep enough.



tobu said:


> Sometimes people race the descents. In those cases, the coaster will get dropped.


????

The coaster merely has to draft the pedaling rider - even if the leading rider is pedaling hard, the drafter frequently has to drag their brakes to stay in the draft.

[


tobu said:


> At high speeds, sometimes an 11 is useful. End of story.


Yeah - its so that the pedaler can sprint with all their might to pick up a fraction of a mile an hour, so that the coaster drafting behind them can get a free ride. At least until the pedaler gets tire, at which point the coaster just pulls into a tight tuck and drops the pedaler like a bad habit.


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## Eric_H (Feb 5, 2004)

*The 11T debate*

This subject gets people almost as excited as Campy vs. Shimano or greased tapers vs. non-greased tapers  

I will say this about the 11T cog. I don't need it. But at the same time I don't need a 25T when racing either. If I'm not getting over a climb in 39x23 then I'm likely dropped. So for race day I use an 11-23 rear. I won't give up the 16T, and while I might never NEED the 11T I have used it in downhill situations from time to time and it has proven to be of some use to me. Plus, the 11-23 is lighter than 12-25 (or 11-25).

My training and general riding is done on 12-25.


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## stevesbike (Jun 3, 2002)

not a lot of that makes sense. If the descent is technical, you'll have to accelerate out of the corners. With an 11 you can hit a higher top speed before being spun out and then you coast. You will get dropped unless you can hit this top speed, end of story. In a race with a fast finish some people also prefer an 11 to have more gear to jump with, including Protour racers like Petacchi. Here's Brett Lancaster's (Milram) description of the stage 1 finish:

"Yesterday's finish was made for McEwen, despite us having a good train going there was just a short straight out of that last corner and he has the explosive power to capitalize on a situation like that. Ale was revved-out yesterday too, he couldn't get the eleven and was sprinting in the twelve."


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## asgelle (Apr 21, 2003)

stevesbike said:


> In a race with a fast finish some people also prefer an 11 to have more gear to jump with, including Protour racers like Petacchi. Here's Brett Lancaster's (Milram) description of the stage 1 finish: ...


I knew Robbie McEwen; Robbie McEwen was a friend of mine; you, sir, are no Robbie McEwen.


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## bill (Feb 5, 2004)

Eric_H said:


> This subject gets people almost as excited as Campy vs. Shimano or greased tapers vs. non-greased tapers
> 
> I will say this about the 11T cog. I don't need it. But at the same time I don't need a 25T when racing either. If I'm not getting over a climb in 39x23 then I'm likely dropped. So for race day I use an 11-23 rear. I won't give up the 16T, and while I might never NEED the 11T I have used it in downhill situations from time to time and it has proven to be of some use to me. Plus, the 11-23 is lighter than 12-25 (or 11-25).
> 
> My training and general riding is done on 12-25.


these are sane words.
if anyone reading this or posting has the power to push an 11 where a 12 truly would be inadequate, that person likely has no business (a) asking or (b) answering this question here, because that person is not the more or less competent senior or masters racer likely to be on this board. that person either is in a different league or kidding himself.


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## stevesbike (Jun 3, 2002)

sorry, but that's just not true. There are many 1/2 and even Masters races that have finish speeds rivaling Protour finishes of 70+ km/hr. If the last few kms involve even a small downhill section they can go easily over 80km/hr. Protour riders do it after riding 200+ km.


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## bill (Feb 5, 2004)

stevesbike said:


> sorry, but that's just not true. There are many 1/2 and even Masters races that have finish speeds rivaling Protour finishes of 70+ km/hr. If the last few kms involve even a small downhill section they can go easily over 80km/hr. Protour riders do it after riding 200+ km.


I said more or less competent. that's like cat 3, 4. if you're a cat 2 or 1, good for you; you don't need my advice and I really don't have much use for yours, on this subject, anyway.
there is a ride every Saturday a.m. around here that ends in a sprint. slightly downhill, usually with a tailwind. mostly racers. lots of 3's and 4's, some 2's, often a few 1's. One of the guys in my club, who is a 2 and one of the best sprinters in the district, wins it in his 12 or 13. I know that I've hit 70 km/hr there, but you can do that in a 12. 
apples to apples, my friend. read what I said.


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## bill (Feb 5, 2004)

and I don't believe that all that many sprints, even Protour sprints, exceed 75 km/hr. the best in the world might go that fast under the right conditions, but you do not see those speeds at your average office park crit. 60 km/hr is more like it.


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## stevesbike (Jun 3, 2002)

well, if you're hitting 70km/hr in your training crit, then you're basically close to spun out in your 12 (120rpm = 67km/hr). Top speeds aren't hit just in the finishing straight- often higher top speeds are hit leading up to the finish, especially if the finish comes out of a technical corner, is slightly uphill etc. If you're spinning out a 12, you're not going to be able to move up for the finish-it's not about what an individual rider can hit by themselves but the dynamics of a pack that ramps up the speed, especially even with the smallest of downhills.


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## tobu (Dec 19, 2004)

People are making the newbie mistake of thinking that riders use the 11 because they can't spin any faster. Many riders aren't truly spun out with a 12, 13, 14, 15, or even 16. Go to the local gym with their exercycle and many riders can hit 170+ rpms. Hell, I've even hit 190+. However, at the end of a race many riders find the slightly lower cadence from the 11 is just more efficient than using a 12, and that the 11 has more "bite". It's not campy vs. shimano -- some people can turn an 11, some people prefer not to. Do what's good for you.


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## ttug (May 14, 2004)

*come again*

While his bike was built for the event, and he was a genetic freak, and it was at Mexico City, Merckx set the hour record in a 52x14.

I know of very few folks who are spun out on a 53 or 52x11 unless you are going downhill on a non technical descent.

While I am very familiar with the numbers at analytic cycling; there are alot of guesses here are to drag. If there are folkas here who can spin out an 11 and know withing a few mm their drag coefficient while never ever having been in a wind tunnel, I would have to guess that this is highly improbable at best. 

As to descending, I think I have cracked 65 mph and that was a very non technical descent and yeah at a point, I tucked, But then again, I was riding a 53x12 and I had just stood up to get the hardest spin I could; then I tucked and spun until I could not make the legs go any faster. Could I have spun more? Sure, If I had trained it, maybe. Was I well over 130 rpm, NO. I was going down hill. 

For folks who are claiming a 160+ cadence, all I have to say is HOW are you calculating your cadence?

The speeds and cadences here are very very high end folks. Lets have a bit of reality here shall we?


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## Kestreljr (Jan 10, 2007)

ttug said:


> While his bike was built for the event, and he was a genetic freak, and it was at Mexico City, Merckx set the hour record in a 52x14.


Who is Mercjkx, and why would we care? I am sure I could kick his tail if he would get out and race me.



> I know of very few folks who are spun out on a 53 or 52x11 unless you are going downhill on a non technical descent.


 I spun out a 54x11 in my last race, going uphill. 



> While I am very familiar with the numbers at analytic cycling; there are alot of guesses here are to drag. If there are folkas here who can spin out an 11 and know withing a few mm their drag coefficient while never ever having been in a wind tunnel, I would have to guess that this is highly improbable at best.


Whatever, I can tell my drag coefficient by the number of rupples my jersey makes on my back. Those wind tunnels are just marketing hype- like carbon. 



> As to descending, _*I think *_I have cracked 65 mph and that was a very non technical descent


*I **think* I crank 65mph on every ride too. We have this in common. 



> For folks who are claiming a 160+ cadence, all I have to say is HOW are you calculating your cadence?


I Count the stokes- this is 5th grade math here. No big deal; I can build rockets- like my bike.



> Lets have a bit of reality here shall we?


Whatever, reality sucks. Then you have to admit that [email protected] ain't true. Who uses that junk while on an online forum.... Newb!


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## stevesbike (Jun 3, 2002)

is it really that hard to understand the difference between riding alone and the dynamics of a large pack? Eddy Merckx's hour record was a solo effort at constant speed. For you guys that don't seem able to comprehend the differences between riding on your own and racing in a pack:

If you rely on coasting down a technical descent in a race you'll get dropped. Attacks will involve accelerating out of corners. It is as easy to drop people going down a descent as going up. Having an 11 is nice to wind it up. If you had to spin at 170rpm out of every corner your hip joints would ignite due to all the heat...

A pack will routinely hit speed of over 70km/hr-thats 20km faster than Merckx's solo hour ride.


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## ttug (May 14, 2004)

*coolio my man*



Kestreljr said:


> Who is Mercjkx, and why would we care? I am sure I could kick his tail if he would get out and race me.
> 
> I spun out a 54x11 in my last race, going uphill.
> 
> ...


My thoughts exactly........


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## ttug (May 14, 2004)

*One more time*



stevesbike said:


> is it really that hard to understand the difference between riding alone and the dynamics of a large pack? Eddy Merckx's hour record was a solo effort at constant speed. For you guys that don't seem able to comprehend the differences between riding on your own and racing in a pack:
> 
> If you rely on coasting down a technical descent in a race you'll get dropped. Attacks will involve accelerating out of corners. It is as easy to drop people going down a descent as going up. Having an 11 is nice to wind it up. If you had to spin at 170rpm out of every corner your hip joints would ignite due to all the heat...
> 
> A pack will routinely hit speed of over 70km/hr-thats 20km faster than Merckx's solo hour ride.


Yes, a pack can hit those numbers.As to the routine issue, UH NO. Think again.

Yes, EVERYTHING changes in a pack hence my comment about drag etc etc etc. 

If you are "winding up" in an 11, you are gearing wrong/over geared and you will get dropped by that weird guy who descended properly and is in a tuck waving at you as he passes by possibly in a 53x14 or better yet, even larger wooo hoo hoo .

NO, you didnt beat Eddy by 20K in a group. You beat him by 20.1, and again, 70K ina group ride is not very common. You know this is a problem here. Guys and gals riding at insane numbers that their computers told them its so. Whats next, 30 mph side winds and your perfect bike handling???


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## stevesbike (Jun 3, 2002)

the line about Merckx was that the peak speed of 70km/hr is 20 km/hr faster than the constant speed of his hour attempt. The entire point is that there is a huge difference between average speed and the variability of speed in a pack over a course with a changing profile...on a technical descent getting aero will play a secondary role to the ability to brake/accelerate out of corners.


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## ttug (May 14, 2004)

*yes, thats so*



stevesbike said:


> the line about Merckx was that the peak speed of 70km/hr is 20 km/hr faster than the constant speed of his hour attempt. The entire point is that there is a huge difference between average speed and the variability of speed in a pack over a course with a changing profile...on a technical descent getting aero will play a secondary role to the ability to brake/accelerate out of corners.


Yes, I agree and understand that. HOWEVER, I just dont get the oh yes, we routinely go 43mph in a pack. No, you dont. If you did, we would be watching you at the TDF.


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