Yes, triathlon bikes are faster

My statement has no context.

Any position you ride in a triathlon you need to be able to run off of effectively.  That should be obvious.

Folks don't run poorly because they ride too low. They run poorly because of poor fitness. If the position is an issue, they are almost always too stretched out, not too low.

I don't sell extreme positions. (I do occasionally ride one).  I sell forward positions with powerful hip angles and properly supported torsos.  The net result of those parameters is the rider generally leaving lower than they arrive. In most cases they are also more comfortable, powerful and able to run afterwards.

Fred, I think there's some truth to what both of you are saying.  Riding lower than a rider is comfortable with and/or adjusted to is detrimental.  If a specific rider finds that an aggressive position leads to digestive problems, then they may want to back off(although I would first look to pacing/fitness before position).

That being said, a low, narrow and aggressive position most likely will be fastest for a rider if they are willing to spend the time to HTFU and acclimate to it.  Due diligence should be done to see how power drops off as the position gets more aggressive, but I think in general, a slick position is a benefit to most people...they just have to be willing to take the time to get used to it. 

I see it as a continuum.  Riders should progressively get lower and more aggressive as their fitness improves and they spend more time riding aero.  Small, incremental changes...

Thing is though, you don't really disagree. (And neither does Tom D. for that matter) Playing the devil's advocate is cool though.

You are speaking of situations that many folks think happen a lot, when actually they happen almost never.

Sure you can ride too low and run bad, and sure you can ride to low and be uncomfortable. Of course triathlon positions need to be workable for triathlons. Not arguing against that. All I fit is triathletes.

What I am saying is that most folks do not run poorly because they are too low. They don't dislike their tri bikes because they are not athletic enough.  They don't ride the same speed as their road bike because they are uncomfortable.

The kicker here is that higher is not necessarily more comfortable, and it is less powerful a lot of the time as well. 

People are afraid to come forward on their seats... heck bike shops that sell Cervelos don't know that that rear hole on the seat post is only for folks who need to fit to UCI regulations.  THAT IS THE ONLY REASON IT EXISTS as per the engineers who designed the bike.

Insisting on sitting slack on a TT bike is very limiting.

Triathlon bikes exist for one reason, and they were designed from the aerobars back. Come forward on the seat so you can ride low in the front while maintaining a powerful hip anlgle. That is all.

Dear readers, Tom D. is correct and Fred D. as well. Thing is, they are correct in a context so narrow, for a population so small, that here and now for all practical purposes, they are wrong.

You sell?

Um, I don't disagree with your premise, and all things being equal, you're right. But all things aren't equal.

I do disagree that a powermeter is necessary to verify the changes, scientifically. Use RPE or HR and speed, that's science, albeit not supported with the number of decimal places of a powermeter. There is plenty of sound science that uses RPE or HR, and plenty of bogus or illiterate science around Powermeters. It goes both ways.  You hit the key: Properly employed.

Another technicality: Narrowing the arms has recently been debunked, at least anecdotally. Cavendish, Sarah Hammer, and others have kept their arms wider because they're not all able to hit the Zabriskie super-narrow position without giving up lung capacity or comfort, and reducing speed. They seem to hit, for them, the best speed with arms wider. So I woudn't take this as a given.

Generally, though, good post. Useful stuff.

Fred, I think there's some truth to what both of you are saying.  Riding lower than a rider is comfortable with and/or adjusted to is detrimental.  If a specific rider finds that an aggressive position leads to digestive problems, then they may want to back off(although I would first look to pacing/fitness before position).

That being said, a low, narrow and aggressive position most likely will be fastest for a rider if they are willing to spend the time to HTFU and acclimate to it.  Due diligence should be done to see how power drops off as the position gets more aggressive, but I think in general, a slick position is a benefit to most people...they just have to be willing to take the time to get used to it. 

I see it as a continuum.  Riders should progressively get lower and more aggressive as their fitness improves and they spend more time riding aero.  Small, incremental changes...

Thanks for the kind words.

When applied to myself, I fully agree with you.  However, given the nature of this site, I don't agree with the "pull the bandaid off" philosophy for everyone.  When you have time and determination to adjust to an "aggressive" position, then making the jump all at once makes sense.  But a lot of people who have intermediate race goals and who might be more recreational focused than performance focused, I'm not sure that it makes a lot of sense to advocate big jumps.

Careful, Dave... You're dangerously close to saying something as blasphemous as "it's not rocket science".

And to the point that your premises aren't necessarily true for the HIM/IM athlete, I'd say that, as you mentioned in your post, for the vast majority of BEGINNERS (as in, the readers of this fine site), the points are dead-on.

I think Dave posted a 29mph average in his last 40k TT.   So you don't have to suspect (unless your name is Phinney or Olheiser or something similar).

Tri-bikes are 1-3 mph faster.  I'll take that.  What about versus a road bike with clip-ons?  1-2 mph faster at best?

I was wondering this myself. Let's say you can pretty closely emulate a tri position on a good quality road bike with, say, FF seat post, aerobars, any other gear you deem necessary, and a damn good fitting.

You're still going to lose time shifting. I understand that.

^^^Taking that into account, what would the gains of a tri bike be over a tri fit on a road bike?

*I* agree with Dave.

NOT being devil's advocate, i truly feel the same.  lets think about this in a math/geometry direction here.

utilizing the FIST protocol there are a set of angles we are trying to achieve.  hip/shoulder/elbow/leg

the way a Tri/TT bike is designed is to allow you to obtain those angles by rotating around the BB as your pivot point.  

you *can* get into a lower and narrower position AND still keep the same appropriate angles from your FIST protocol.  

if you are comfortable AND powerful in one position, i can with almost 100% certainty say there is a way to get you LOWER without changing your position angles.  there IS a bike/bar/extension/pad/stem combo out there that will allow for you to rotate your position without changing any other geometry. (unless you are of some weird size like Matty Reed)

the Narrow part i DO feel is subject to the length of the riders Humorous bone as the shorter they are the less narrow you can get your elbows as they will restrict your breathing at some point.  BUT chances are, you are NOT at that point now.

 a lower frontal area at the same wattage (maybe even less!) will be faster!

i bet Dave COULD ride that position and run off from it no different.  like he said it's not the position that makes the run bad....... it's all the other crap.

Math.... it's what's for dinner!

I'm no certified fitter or pro triathlete or coach.. but..

I would imagine you would want to be as low as you can COMFORTABLY go.  I do believe it will be faster than a road bike simply based on aerodynamics of the TT position vs road position. 

Example:

a few weekends ago I was riding with a friend. He is a much better cyclist than I am. We were on flat (i mean real flat) surface and had a real bad head wind of at least 20mph constant.  he was on a road bike (Bianchi) , me on my Tri bike (Litespeed).  I got into my aero bars and head down and just pedaled.  I looked up about 10min later and my buddy was way behind me. Couldnt even come close to keeping up with me.

Proved it for me.

Fred and all, the respect is mutual. And I agree with you guys, in that you can't compromise your race for a postion.  My entire pont is that almost everyone lurking on this site does not need to worry about that because they have much more room to get aero before that race is compromised. I think overemphasis on the "don't ride too low because it will effect..." is somewhat a disservice.

As far as my avatar position goes, the radical stuff there is not the hip angle, knee angle or aerobar drop. Beleive it or not that is an ideal 100 degrees of hip angle at a fairly forward 82 degrees of seat tube angle and 15 cm of aerobar drop.  The outlying measurement is shoulder angle (cockpit distance).  I am waaaaay stretched out at over 110 degrees of shoulder angle. 90 cm of cockpit compared to 78 cm of seat height is a little nuts. The other radical bit is my width, or lack of. I am riding very narrow there.  Also, I am able to physically lower my head and hold it very low, very well. It is also very stressful on my neck. I would probably do this less as the triathlon race distance increased, but it would require no change to the bike for me to do this.

I am going to run this exact set up in a sprint in 1 week and see how it goes. I full expect to need to bring the cockpit in a bit to not compromise my running at some distance, but I am going to play the wait and see game first. I have ridden that position a lot and I am going out for another 2.5 hours here shortly with a brick run after.