behind the seat bottles? - yes or no

Hi,

A recent tri magazine published an article on the aerodynamic disadvantage to having bottles mounted
behind the seat versus the traditional positions on the frame.

What's the current belief out there? Was this "article" actually an ad for a certain drinking
system, or is there actually real hard science out there? Or doesn't it really matter and it's more
personal preference?

I've seen both set ups in the amateur and professional ranks.

Brian

 

"Brian and Denise Pauley" <[email protected]> wrote in news:[email protected]:

> Hi,
>
> A recent tri magazine published an article on the aerodynamic disadvantage to having bottles
> mounted behind the seat versus the traditional positions on the frame.
>
> What's the current belief out there? Was this "article" actually an ad for a certain drinking
> system, or is there actually real hard science out there? Or doesn't it really matter and it's
> more personal preference?
>
> I've seen both set ups in the amateur and professional ranks.
>
> Brian
>
>
>
>
>

I'm sure that it's better to tuck them behind the rider rather than out front. I also suspect that
the real impact of doing this is very minor, particularly for those of us who aren't averaging 25
mph or higher over a 112 mile course. The faster you're moving, the more important aerodynamic
advantage is. I have a behind the seat setup, mostly because my softride doesn't have any other
place to put two bottles. I doubt that the .5 seconds it gains me over a 56 mile course will change
my results at GCT in May.

We've had similar discussions about fastskin swimsuits. They do much more good for a WR holder than
for the average masters swimmer.

Tom

 

Bzzzt. Sorry Tom. John Cobb did some extensive testing and determined that putting the bottles on
the frame was actually more aerodynamic. The basic theory is that it aided the frame in becoming
"sail-like" and therefore more added to the aero advantage while riding.

But that being said, speed is definitely a consideration and comfort. Just like you could probably
be in a more aero position, if you are uncomfortable for 112 miles (especially if it will affect
your run) it's useless. If you are used to using the behind the seat cages then that may be better
than getting used to frame mounted cages.

There was an article on John Cobb's web page but for some reason I can't find it anymore. Here's a
link to a recent post by him about bts (behind the seat) cages... that kinda talks about it.

http://www.bicyclesports.com/forum/ShowPost.aspx?PostID=437

-Andrew Boulder, CO

Tom Henderson wrote:

> I'm sure that it's better to tuck them behind the rider rather than out front. I also suspect that
> the real impact of doing this is very minor, particularly for those of us who aren't averaging 25
> mph or higher over a 112 mile course. The faster you're moving, the more important aerodynamic
> advantage is. I have a behind the seat setup, mostly because my softride doesn't have any other
> place to put two bottles. I doubt that the .5 seconds it gains me over a 56 mile course will
> change my results at GCT in May.
>
> We've had similar discussions about fastskin swimsuits. They do much more good for a WR holder
> than for the average masters swimmer.
>
> Tom

 

Bzzzt. Sorry Tom. John Cobb did some extensive testing and determined that putting the bottles on
the frame was actually more aerodynamic. The basic theory is that it aided the frame in becoming
"sail-like" and therefore more added to the aero advantage while riding.

But that being said, speed is definitely a consideration and comfort. Just like you could probably
be in a more aero position, if you are uncomfortable for 112 miles (especially if it will affect
your run) it's useless. If you are used to using the behind the seat cages then that may be better
than getting used to frame mounted cages.

There was an article on John Cobb's web page but for some reason I can't find it anymore. Here's a
link to a recent post by him about bts (behind the seat) cages... that kinda talks about it.

http://www.bicyclesports.com/forum/ShowPost.aspx?PostID=437

-Andrew Boulder, CO

Tom Henderson wrote:

> I'm sure that it's better to tuck them behind the rider rather than out front. I also suspect that
> the real impact of doing this is very minor, particularly for those of us who aren't averaging 25
> mph or higher over a 112 mile course. The faster you're moving, the more important aerodynamic
> advantage is. I have a behind the seat setup, mostly because my softride doesn't have any other
> place to put two bottles. I doubt that the .5 seconds it gains me over a 56 mile course will
> change my results at GCT in May.
>
> We've had similar discussions about fastskin swimsuits. They do much more good for a WR holder
> than for the average masters swimmer.
>
> Tom

 

I just read that also and I think you have to take it with a grain of salt. They said the test rider
didn't break aero position, which is why the behind the seat was less aero. Myself I need to break
aero sometimes to stretch, climb, etc. Also 2-3 minutes over 5 hours isn't a huge thing.

TriRod IMC 2002 IMUSA CdA 2003

Brian and Denise Pauley wrote:

>Hi,
>
>A recent tri magazine published an article on the aerodynamic disadvantage to having bottles
>mounted behind the seat versus the traditional positions on the frame.
>
>What's the current belief out there? Was this "article" actually an ad for a certain drinking
>system, or is there actually real hard science out there? Or doesn't it really matter and it's more
>personal preference?
>
>I've seen both set ups in the amateur and professional ranks.
>
>Brian
>
>
>
>

 

Andrew Halperin <[email protected]> wrote in news:[email protected]:

> Bzzzt. Sorry Tom. John Cobb did some extensive testing and determined that putting the bottles on
> the frame was actually more aerodynamic. The basic theory is that it aided the frame in becoming
> "sail-like" and therefore more added to the aero advantage while riding.

OK, I stand corrected, I guess. I still think that none of it makes as much difference at the speeds
that most mortals ride at.

>
> But that being said, speed is definitely a consideration and comfort. Just like you could probably
> be in a more aero position, if you are uncomfortable for 112 miles (especially if it will affect
> your run) it's useless. If you are used to using the behind the seat cages then that may be better
> than getting used to frame mounted cages.
>
> There was an article on John Cobb's web page but for some reason I can't find it anymore. Here's a
> link to a recent post by him about bts (behind the seat) cages... that kinda talks about it.
>
> http://www.bicyclesports.com/forum/ShowPost.aspx?PostID=437
>
> -Andrew Boulder, CO
>
> Tom Henderson wrote:
>
>> I'm sure that it's better to tuck them behind the rider rather than out front. I also suspect
>> that the real impact of doing this is very minor, particularly for those of us who aren't
>> averaging 25 mph or higher over a 112 mile course. The faster you're moving, the more important
>> aerodynamic advantage is. I have a behind the seat setup, mostly because my softride doesn't have
>> any other place to put two bottles. I doubt that the .5 seconds it gains me over a 56 mile course
>> will change my results at GCT in May.
>>
>> We've had similar discussions about fastskin swimsuits. They do much more good for a WR holder
>> than for the average masters swimmer.
>>
>> Tom
>

 

On 4/8/03 10:18 AM, in article "Andrew" <[email protected]> wrote:

> Bzzzt. Sorry Tom. John Cobb did some extensive testing and determined that putting the bottles on
> the frame was actually more aerodynamic. The basic theory is that it aided the frame in becoming
> "sail-like" and therefore more added to the aero advantage while riding.
>
> But that being said, speed is definitely a consideration and comfort. Just like you could probably
> be in a more aero position, if you are uncomfortable for 112 miles (especially if it will affect
> your run) it's useless. If you are used to using the behind the seat cages then that may be better
> than getting used to frame mounted cages.
>
> There was an article on John Cobb's web page but for some reason I can't find it anymore. Here's a
> link to a recent post by him about bts (behind the seat) cages... that kinda talks about it.

Do you remember if Cobb addressed aero bar mounted bottles in the testing? Where did they fall in
the mix (I'm guessing worst of the three locations).

But.... IMHO I'm with Tom on this. I can't believe that where I put my bottle is going to suddenly
pop me to the top of my age group.

John

 

The best aero position ain't necessarily the best place to have a bottle. Bar mounted bottles allow
you to drink smaller amounts more often and stay in the aero position, thereby giving you much more
advantage than the slight aero advantage of mounting elsewhere. Again, for mere mortals,
convenience, price and availability is everything.

"John Hardt" <[email protected]> wrote in message news:BAB8EFB9.963%[email protected]...
On 4/8/03 10:18 AM, in article "Andrew" <[email protected]> wrote:

> Bzzzt. Sorry Tom. John Cobb did some extensive testing and determined that putting the bottles on
> the frame was actually more aerodynamic. The basic theory is that it aided the frame in becoming
> "sail-like" and therefore more added to the aero advantage while riding.
>
> But that being said, speed is definitely a consideration and comfort. Just like you could probably
> be in a more aero position, if you are uncomfortable for 112 miles (especially if it will affect
> your run) it's useless. If you are used to using the behind the seat cages then that may be better
> than getting used to frame mounted cages.
>
> There was an article on John Cobb's web page but for some reason I can't find it anymore. Here's a
> link to a recent post by him about bts (behind the seat) cages... that kinda talks about it.

Do you remember if Cobb addressed aero bar mounted bottles in the testing? Where did they fall in
the mix (I'm guessing worst of the three locations).

But.... IMHO I'm with Tom on this. I can't believe that where I put my bottle is going to suddenly
pop me to the top of my age group.

John

 

In article <[email protected]>,
"roofi" <[email protected]> wrote:

> Do you remember if Cobb addressed aero bar mounted bottles in the testing? Where did they fall in
> the mix (I'm guessing worst of the three locations).
>
> But.... IMHO I'm with Tom on this. I can't believe that where I put my bottle is going to suddenly
> pop me to the top of my age group.

What if you put it through the spokes of your main competition?

--Harold Buck

"I used to rock and roll all night, and party every day. Then it was every other day. . . ."

- Homer J. Simpson

 

If it was an ad for the Neverreach system that reported estimates of aero drag based on field tests
with a power meter, I'd say don't believe the data that were presented. Simply put, you can't detect
such small differences that way.

Andy Coggan

"Brian and Denise Pauley" <[email protected]> wrote in message
news:[email protected]...
> Hi,
>
> A recent tri magazine published an article on the aerodynamic disadvantage to having bottles
> mounted behind the seat versus the traditional positions on the frame.
>
> What's the current belief out there? Was this "article" actually an ad
for
> a certain drinking system, or is there actually real hard science out
there?
> Or doesn't it really matter and it's more personal preference?
>
> I've seen both set ups in the amateur and professional ranks.
>
> Brian
>
>

 

"Andrew" <[email protected]> wrote in message news:[email protected]...

> John Cobb did some extensive testing and determined that putting the bottles on the frame was
> actually more aerodynamic. The basic theory is that it aided the frame in becoming "sail-like" and
> therefore more added to the aero advantage while riding.

For bikes with non-aero downtubes, that is. For bikes with aero downtubes, John's recommendation is
to put the bottle on the seattube, as it *hurts* the aerodynamics the least that way.

Andy Coggan

 

On 4/9/03 1:06 AM, in article, "Harold Buck" <[email protected]> wrote:

> In article <[email protected]>, "roofi" <[email protected]> wrote:
>
>> Do you remember if Cobb addressed aero bar mounted bottles in the testing? Where did they fall in
>> the mix (I'm guessing worst of the three locations).
>>
>> But.... IMHO I'm with Tom on this. I can't believe that where I put my bottle is going to
>> suddenly pop me to the top of my age group.
>
>
> What if you put it through the spokes of your main competition?

Still wouldn't work. At my last race, I would have needed about 35 bottles to get to the top of my
age group.

John

 

"Andy Coggan" <[email protected]> wrote in message
news:[email protected]...
| "Andrew" <[email protected]> wrote in message
news:[email protected]...
|
| > John Cobb did some extensive testing and determined that putting the bottles on the frame was
| > actually more aerodynamic. The basic theory is that it aided the frame in becoming "sail-like"
| > and therefore more added to the aero advantage while riding.
|
| For bikes with non-aero downtubes, that is. For bikes with aero downtubes, John's recommendation
| is to put the bottle on the seattube, as it *hurts* the aerodynamics the least that way.
|
| Andy Coggan
|
|

It amazes me that Profile are the only makers of an aero shaped water bottle, and even their setup
is pretty pathetic. The first person to start making aero water bottles for the downtube will become
rich very quickly. Shimano made them for a while in the 600AX ? days but that was before triathlon
and tribars were around.

Marty

 

> It amazes me that Profile are the only makers of an aero shaped water bottle, and even their setup
> is pretty pathetic. The first person to start making aero water bottles for the downtube will
> become rich very quickly. Shimano made them for a while in the 600AX ? days but that was before
> triathlon and tribars were around.
>
> Marty
>

I believe that campy makes an aero bottle and that came out quite some time ago.

I don't know it they are still in production

JJ

 

I agree with most of what's been said. Understand that the differences are significant in a 56 or
112 mile ride--not just a second or two but maybe 30 seconds. Again, if you're just an age grouper
not trying to qualify for Kona, that doesn't matter. But I have won races (masters overall division)
by 12 seconds with a disc wheel, and new if I had decided it was too hilly and brought another
wheel, I probably would have lost.

Yes, John Cobb says that mounting on the bike frame is better than behind the seat. But if you have
a Zipp or other beam bike that does not support frame-mounted bottles, you pretty much HAVE to put
it behind the seat, especially if you want to carry more than one bottle. Yes, it's true the
front-loading aerobar bottles like Profile and such do cause some drag, but if you're in a hot race,
short or long, the ability to sip continuously is a big advantage not just on the bike, but on
coming off for the run feeling well-hydrated. Cobb says this is much more important than the drag
factor. No use gaining 30 seconds of drag advantage only to bike and run five minutes slower since
you were too tired or forgot to reach for the water bottle. On courses like Buffalo Springs half- or
Kona full-Ironman, having that straw stuck in your face the whole ride makes it hard to forget. It's
also nice on peleton training rides, to be able to space your distraction to every 45-60 minutes,
without having to drink while others are attacking.

You also see a lot of pros using XLab rear setups just because they like it for tires and such in
longer races. I think they know it's a bit less aero, and they are heavy, but they are so damned
convenient. You also see a lot of pro men NOT using front water bottles to gain a bit of advantage,
but they are actually RACING on the 112-mile bike, not just pacing and hydrating.

I think a lot of it is personal preference. Some folks just get used to reaching for water bottles a
certain way and don't want to change. I used to take my aero-water bottle every ride, training and
racing, in heat and humid-prone Texas. Now I just take it on rides over two hours or races. Some
folks just think they are silly and don't want the hassle of cleaning and filling them (same with
CamelBak, an excellent device but a hassle to many).

One other thing VERY important you can learn from ultracyclists and Tour riders is to climb steep
hills the minimum amount of water, and descend with lots of water. The extra couple of pounds is
quite significant. If you think you are in an Ironman with climbs at mile 30-40 (e.g., Kona), you
might want to take enough water for that. If there's lots of climbing right out of the water (e.g.,
Buffalo Springs), then take maybe only one bottle and load up more on the course. If you have a
support crew or aid stations near the top of a hill, pickup one or two bottles for the descent--you
do go a bit faster, and there's less to load up with later.

But Cobb is insistent that hydration and comfort is more important that aerodynamics no matter what
the wind-tunnel says. Once you have attained these goals, whatever you can do to decrease drag while
still feeling okay you should try. Experiment on training rides and find out what you like.
Confidence is by far the biggest speed enhancer.

"Brian and Denise Pauley" <[email protected]> wrote in message
news:[email protected]...
> Hi,
>
> A recent tri magazine published an article on the aerodynamic disadvantage to having bottles
> mounted behind the seat versus the traditional positions on the frame.
>
> What's the current belief out there? Was this "article" actually an ad
for
> a certain drinking system, or is there actually real hard science out
there?
> Or doesn't it really matter and it's more personal preference?
>
> I've seen both set ups in the amateur and professional ranks.
>
> Brian
>

 

FYI, there was an article in Triathlete recently where they did a thorough analysis of the
aerodynamic costs/benefits or various drinking systems.

-Harold

 

No

 

On 4/21/03 5:34 PM, in article [email protected], "Harold Buck"
<[email protected]> wrote:

> FYI, there was an article in Triathlete recently where they did a thorough analysis of the
> aerodynamic costs/benefits or various drinking systems.
>
> -Harold

That was partially an ad........

Sam

 

The bean is right. It's all crap in those mags. They are all ads in disguise. Ever notice how ads
are placed closed to the articles that plug 'em? All crap, I say.

Sam Bean <[email protected]> wrote in message news:<BACCBFDE.78E%[email protected]>...
> On 4/21/03 5:34 PM, in article [email protected], "Harold Buck"
> <[email protected]> wrote:
>
> > FYI, there was an article in Triathlete recently where they did a thorough analysis of the
> > aerodynamic costs/benefits or various drinking systems.
> >
> > -Harold
>
> That was partially an ad........
>
> Sam