# To aero bottle or not to aero bottle?



## multirider (Nov 5, 2007)

I have a Specialized Transition TT bike and a Profile aero bottle.

Click here to see a bike that looks almost exactly like mine: 

Click here for a picture of a bike like mine with a bottle like mine

The bottle and cage weigh 110g. Not consequential for a 25 minute time trial over rolling terrain. I don't need hydration for a 25 minute race, so the bottle is not necessary.

I average 25.2mph with a max of 42.8mph. Aero is a big factor.

Does it look like the bike would be more or less aero with the bottle? I can run it empty if more aero. 

It blends with the frame pretty well, is pretty narrow, and nicely rounded. It kind of fills the frame like a Specialized Shiv or Cervelo P4. But not nearly as smoothly and completely.

More aero with the bottle? Or without? Opinions and guidance? Thanks!


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## Local Hero (Jul 8, 2010)

I have not seen definitive wind tunnel on this but I run a bontrager bottle on my Trek speed concept. I drink from it during the warmup and on training rides. At the TT I will take sips while waiting for my start. This is worth it for me. It is nice when I do not have to start with a dry mouth, even if there is a few watts penalty (or a few watts gained). If I do remember to drink during the TT, it's usually just a single sip. 

The wind tunnel tests I have seen say that a bottle between the arms (BTA) may improve aerodynamics. 

EDIT: Conflicting info on the bottle BTA; 
AeroGeek?s Hydration Guide ? BTA | AeroGeeks

Profile Design Aero HC Aerobottle + Bike Computer Mount Review | DC Rainmaker

http://www.slowtwitch.com/images/trek/TK13_SC_Whitepaper_final.pdf


MOAR: TriRig.com - Hydration Guide 2015


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## multirider (Nov 5, 2007)

I need to look at the links you provided, planning to do that tomorrow.

I found this from Cervelo saying all bottles on the frame are slower except their bottle on the P4. It also says the bottle between the arms is lower drag.

This bottle for Specialized bikes looks a lot like the bottle for the Cervelo P4.

Here's the Cervelo P4 with bottle

The P4 bottle is a few clicks more custom fit to the frame, but the Specialized Virtue appears to be pretty close to the naked eye. But how about the wind tunnel??

I took 5th in my last race by 1.5 seconds. If a bottle would help me move up a spot, I'm in !


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## pedalbiker (Nov 23, 2014)

I don't think the BTA bottle is legal.


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## Local Hero (Jul 8, 2010)

pedalbiker said:


> I don't think the BTA bottle is legal.


UCI requires bottles to be mounted in the main triangle. Are we talking about UCI races?


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## kbiker3111 (Nov 7, 2006)

Why not just use the specialized Virtue bottle? It fits perfectly with the Transition frame and I've heard its aero neutral. I use it not for aerodynamics but the convenience of having a handy bottle during warm ups and cool downs.


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## multirider (Nov 5, 2007)

Not a UCI race. Just a weekly series in Denver.

I'm looking for improved aero over just the bare frame and the Virtue looks like it might be, but it would be great if there was an actual test of it. I searched YouTube for the Specialized Win Tunnel, found an episode about round bottles for CX and a video for a lot of stuff on a TT bike for an Ironman, but didn't find a test of the Virtue.

I'm leaning towards just skipping it.


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## Local Hero (Jul 8, 2010)

kbiker3111 said:


> Why not just use the specialized Virtue bottle? It fits perfectly with the Transition frame and I've heard its aero neutral. I use it not for aerodynamics but the convenience of having a handy bottle during warm ups and cool downs.


That's what the tririg article says: 

_If you decide that you absolutely need to put a bottle on your frame, an aero bottle is preferable to a round one. Specialized, Arundel, Bontrager, and Profile Design all make good aero bottles, but some of them integrate better with certain frames than others. If you have a Specialized bike, get the Specialized Virtue bottle and mount it on the downtube. If you have a Trek, get the Bontrager and mount it on the seat tube (it fits better there). _
TriRig.com - Hydration Guide 2015


multirider said:


> Not a UCI race. Just a weekly series in Denver.
> 
> I'm looking for improved aero over just the bare frame and the Virtue looks like it might be, but it would be great if there was an actual test of it. I searched YouTube for the Specialized Win Tunnel, found an episode about round bottles for CX and a video for a lot of stuff on a TT bike for an Ironman, but didn't find a test of the Virtue.
> 
> I'm leaning towards just skipping it.


A viable option...unless it is 90 degrees out 

_The general rule is that if you're using an aero frame bottle, try to put it where it better "completes" the shape of your bike without leaving gaps. Otherwise, try to leave your frame bare, so its aerodynamics can work as designed. In short, the frame bottle should be your last stop, or last resort, for finding a good hydration solution._
TriRig.com - Hydration Guide 2015



EDIT: It turns out someone at Specialized put the transition though a wind tunnel with a Virtue bottle on it. The results: No real change. 

Slowtwitch Forums: Triathlon Forum: Re: Drag differences (watts or seconds per 40k) for different bottle set ups [FatandSlow]: Edit Log

*The Virtue aero bottle tucked into the ST/DT/BB area shows little to no drag increase over a bare Shiv or Transition (usually +/- 5 gF). If you're trying to carry 20ish ounces of fluid during a TT or short tri, this is the way to go.*


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## spade2you (May 12, 2009)

I'd say to experiment if it's a weekly series. Take a look at the wind conditions, power, and average speed and see if you can find correlations.


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## Local Hero (Jul 8, 2010)

For me, the biggest advantage is having fluids right up until I start. As I said earlier, if I take a sip during the TT it is usually a single sip, right at the turnaround. I try to do the Carbo Rinse.

_Back in 2004, Carter and Jeukendrup (Med Sci Sports Exercice 2004, 36: 2107-11) had already verified an improvement of 2.9% compared to controls in a time trial effort of cyclists performing a 5 seconds mouth rinse with a solution of CHO every 8 minutes, without swallowing such solution. 

Furthermore, Chambers and Al (J Physiol 2009, 587:1779-94) confirmed an improvement of 2-3% with mouth rinses of glucose and maltodextrin solutions at 6%, lasting 10 seconds every 8 minutes of effort; with the help of magnetic resonance (MRI), they noticed the activation of brain areas related to motivation and gratification during exercise. The artificial sweetener placebo did not improve the performance nor activate brain areas. 

Pottier et al (Scand J Med Sci Sports 2010, 20:105-111) verified on 12 triathletes an improvement of 3.7% during a 1 hour time trial effort compared to placebo, confirming that the rinse decreased the perception of fatigue allowing to develop a higher power output. _​

Maybe a perpetuem solid would have the same effect taken midrace. 

(Sorry if I am spamming up this thread with so many posts, I have put a lot of thought into improving my TTs this year.)


Back on track--to the question of how to improve aero in a TT--the TriRig Omega SV would certainly give some aero benefits over the transition's stock two-post brakes.


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## mimason (Oct 7, 2006)

I would not use a bottle and I would remove the cage. Warm ups can easily be done without a bottle(hydrate before and after etc) or warm up on a trainer(if you race tubulars) etc.

At times I would keep a bottle between the aero bars if I wanted a sip. For the race if you drink you lost valuable time. 

My understanding also is that most bikes are more aero without bottles....think side winds too.

If you don't have a skin suit get one. If you don't use a skin suit you can put a bottle in your middle pocket for warmups.


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## burkeqc (Sep 25, 2006)

I use the Specialized Virtue, mainly because of the short (20K) TTs I do. (I'm 74). I don't drink during the event, but warming up, cooling down & for training it comes in handy. Its not as aero as BTA, but it works for me. I tried the Profile frame bottle, but cap was very hard to get off & I tried 2, same deal. For the Virtue, cap assembly must taped, a minor issue.


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## multirider (Nov 5, 2007)

Local Hero -- Excellent info! I very much appreciate it! I went 8 seconds faster yesterday than the previous week (primarily due to better pacing and to taking some corners faster) and finished up one spot, in 4th. Faster faster faster!


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