1.Rider position (depending on how much and what you change)
2.Aero wheels
3.Aero Helmet
4.Aero Frame/Fork

these are the most significant things the others are minor.
body shape takes a long time to change.

I would say
Rider position
Aero helmet
Wheels
Frame

My guess is rider position is 70% of the total, so more important than the others combined. Only problem is position requires wind tunnel testing, the others are generally more easy to measure, except for the "best" helmet, but an aero helmet will usually be faster than a road helmet, no matter which one you choose.

also depends what distance you are racing being in a aero as possible position wont make you any faster if you are not comfortable

Funny.....but there seems like an inverse relationship with the $ spent vs. actual benefit. Body positioning and helmets generally trump frames and wheels.

If you're really on a budget, I'd further break the wheels up. The front wheel is much, much more important than the rear.

---

Steve

"If you ain't first, you're last." Reese Bobby Talladega Nights

Don't forget the field of Facial Aerodynamics. There was a very detailed study done a few years back, the URL escapes me now, but I believe the picture up top represented the better findings.

1. position
2. tires (if you inlucde CRR)
3. the totality of not having a bunch of shit hanging off your frame
4/5: frame/wheels (tie?)
6. helmet
5. cockpit
6. fork
7. cables
8. shoes

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

http://www.socalttseries.com/...al-aerodynamics.html

Aerodynamics for Time Trial Racing - Where to invest upgrade dollars when considering new equipment and gear.

I haven't seen anyone mention skin suits, but some of the most dramatic improvements we've seen (other than positioning) were due to changing from shiny short-sleeved kit into long-sleeved, textured skinsuits.

"Skin is slow."
-- Paul Harder, Trek Engineer

---

AndyF
bike geek

What are some brands/models that are pretty legit that you have seen?

I just have a basic champsys. If I went fancy would I break the sound barrier?

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

the basic champsys was slower for me than the team run of the mill suit.

the thought was the texture all the way along the flat torso/back was texture in the wrong place

I've personally seen good improvements with one of the newer Champ-Sys cycling speed suits, although I'm not sure if it's out yet. And the Pearl-Izumi Octane trisuit tested pretty well, too.

For a more complete list I'll defer to Jim Manton, who has probably seen a lot more tests.

---

AndyF
bike geek

Only problem is position requires wind tunnel testing

Not.

Though it is hard to do accurately without a PM. But even then you can look at frontal area and smart practices.

"Skin is slow."
-- Paul Harder, Trek Engineer

Hairy skin is probably worse...

I have a textured Voler suit... but it doesn't seem to be any lower drag than my old and smooth ones. I'd happily spend $300 on a new suit if I thought it would reduce my CdA by 5% or better.

1. Position
2. Clothing
3. Helmet or Wheels
4. Helmet or Wheels
5. Clean front end (i.e.cables)
6. Proper hydration setup
7. Frame

Castelli Body Paint II seems to be very consistently fast. Champion Systems is coming out with a VERY good skin suit. For tri, you're giving up minutes if you're not using a Pearl Izumi Tri Octane. Seriously, that suit is amazing.

---

Jim Manton / ERO Sports

Always listen to the best bike fitter on the planet! Jim set me up in a perfect tt position, one I've been able to ride in for rides as long as 138 miles with very minimal time out of the extensions.

Now I need to work on the motor...

Can you point out key differences between the Pearl Tri Octane suit and a skin suit? It looks like they are close to one in the same.

---

24 Hour World TT Champs-American record holder
Fat Bike Worlds - Race Director
Insta: chris.s.apex

Have you tested the LG Course TT skinsuit?

Maybe... better positioning isn't necessarily free, depending on where you start and what sort of equipment choices may facilitate positioning improvements. It *could* be as simple as moving your saddle forward and/or flipping the stem/spacers; or, it could lead to new saddle, bars/stem, even a new frame, etc. I was kind of at the limit of where I could get with my old converted road frame & bent forward seatpost, for example, so buying a TT/Tri-specific frame accomplished both position gains as well as reduced drag of the frame itself.

Minutes? For what distance?

---

---

http://www.frostyjunction.com/
https://twitter.com/FrostyJunction

One thing you might do -- particularly for those on a budget -- is separate front and rear wheel. As I understand it, a front aero wheel gives you a much bigger improvement than a rear.

Jim has more experience testing than everyone else here combined, so you have your answer.

I would add that number 1 is by far the most important. I can get 80% of the entire benefit from just position (as long as clothing is decent tight fitting cycling uniform type stuff). So if you want to save money just do lots of aero testing and refine your position. Once there buy a good skin suit and helmet and, to be honest, you've got most of what you're going to get right there.

Castelli Body Paint II seems to be very consistently fast.

Thanks Jim! Can you give an idea of the drag reduction compared to...?

And also always curious as compared to what? Like is it minutes over cargo shorts and and a hoodie or minutes over the last skin suit?

Not saying the info isn't valid but that often seems to be glanced over.

Like the link above to some TT testing saying that there was something like 2-4 minutes to be found with aero wheels over 32 spoke box rim wheels, but really how many people are jumping from that to aero wheels and not something that is 20-24 spokes and already slightly aero? Heck the 10 year old (ok I replaced the rear) wheels I use off my trek 1500 weren't 32 spoke box wheels.

It's kind of like if Ford said the new GT500 makes 4X the power of the old mustang.. but they didn't mean the 12' GT500 they meant a base 4 cylinder fox body.


Again not saying someone is misrepresenting things just sometimes it is hard to decipher if the new shiny takes minutes off last weeks now old shiny or the 10 year old never was shiny.

It's tri-specific, so seems to be more comfortable to run in.

All clothing is dependent on how it fits you, but I believe the next big revolution in aero is clothing, likely custom fitted.

To answer someone else's question, the Tri Octane has measured to about 5 minutes over the course of an Ironman vs a fairly typical sleeveless two-piece "club" tri suit. In the end, though, you need to cover your skin with as few wrinkles as possible, and you need textured fabric to act as a boundary layer trip for your upper arms.

Jackmott is correct about tires/Crr, and I would add how those tires interact with specific wheels.

The scariest thing to put on yourself are booties. Talk about personal...they make helmets easy to figure out! Most seem to be very bad, though we tested some Castelli's last week that worked very well for the client. When they're slow, they're really slow. Shocking, actually.

Lanierb - wow, thanks, that flattering coming from someone like you.

Okay, clients are coming in for the day. I'm off the grid until tonight, but I'll try to check in. Sorry.

---

Jim Manton / ERO Sports

Thanks Jim! That is actually really exactly what I was looking for, just a reference point. Not sure when I'll be at the point where I even consider one but good to know, a big bearded guy in a skinsuit is making me chuckle though.

Has anyone tested stretched ears? what about tunnels vs plugs? :) (obviously doesn't matter since most aero helmets cover your ears just one of this things I think about)

As always, thanks for chiming in, Jim.

I think this has been asked before, but I don't remember if you ever replied. Have you only tested (breathable) lycra shoe covers or also the PU-coated (non-breathable) ones? It's been assumed for a while that the lycra ones are no good, while the PU-coated ones might be good. Also, a tight fit around the ankle is likely pretty important, too.

Which Castelli ones did you test with good results on the client? Their dimpled 'Aero Race' (and lycra, I think) or their PU-coated 'Nano'?

Thanks for the info on the Champ-Sys skinsuit, will have an eye out for that one. So we're down to Castelli and the coming Champ-Sys being good, while I would think the new Bioracer could also be pretty good since they claim to have spent a lot of hours in the wind tunnel developing it and they seem to get the idea, as you suggest with the arms, to roughen up the fabric on the arms and shoulders while keeping it smoother further down the body. I have no data on it, though, only conjecture! But Tony Martin and Sky is racing in it so clearly it can be fast :p

ah yes I know just the pic you're thinking of lol

I'm often surprised that people ignore clothing as a potential area for improvement. Some of my very first field tests were done with a constant position so I could nail down the calculations and protocols but my jerseys and shorts would change depending on the status of my laundry hamper. At first I thought there was something wrong with my calculations because I was getting huge differences in my estimated CdA. After a while I figured out that I was picking up differences in the jerseys. Whether the zipper is all the way up or part way down can be also pretty easy to see.

Chung I always do my field tests with a skin suit for that reason.

I'm still not good at field tests though =)

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Well, that's cuz you've bought into the idea and usefulness of field tests. When I first started doing them, especially on the kinds of venues I was using, I thought it was kind of a parlor trick.

Me neither. You should hear about some of my field testing failures. Tom A. is pretty good at it, though. Damn him.

Hello scofflaw and All,

Here is some more info:

http://www.view-speed.com/time_saved.html

Cheers,

Neal

+1 mph Faster

Great to hear the thoughts from someone with a lot of experience in the wind tunnel!

Booties is the same as socks, right? I am Norwegian and av never heard the word before and google translate translated it to socks but I did not see a lot of socks pictures when I googled the word.

How about compression calfs? Have any experience with that?

Beeing a couple of hours in the R J Mitchell wind tunnel in Southampton was a revelation for me and extremely interesting. Unfortunately my triathlon clothing was not available when I went so I could not compare it to a skin suit etc.

But I agree with you that aero clothing is the new "big thing", and I think the general focus on aerodynamics is going to be increased a lot.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

After seeing the PI octane up close, I'd have to say that I would only consider it for wetsuit legal racing.

 
Booties is the same as socks, right? I am Norwegian and av never heard the word before and google translate translated it to socks but I did not see a lot of socks pictures when I googled the

Booties are overshoes - google "cycling booties", can be used for warmth or waterproofing, also for drag reduction for time trialling.

When it comes to the hierarchy I will agree with most of the other on this forum.

1. Bike position (the biggest single aerodynamic factor by far)
2. Clothing or TT-helmet
3. Clothing or TT-helmet

I did not test any low profil wheels, but did not find a big differance in Zipp 808 rear and Zipp Sub 9 disk. About 20 g in both 0 and 7,5 degrees yaw.

When it came to helmets I found big differance between different TT-helmets. Compared with the best TT-helmet the worst produced 150 g more drag (about 6,5 % of the total drag) and a road helmet 100 g more then the worst TT-helmet. Then we got 250 g between the best TT-helmet and a road helmet (ordinary road helmet which the producer claims to have good aerodynamic to be a road helmet).

I guess you could get a 250 g difference between clothing as well, but I presume that everyone with aerodynamics in their mind at least race in tight clothing. Then again, not everyone got aero in their mind and that was pretty obvious under Norseman were we are required to wear a reflective vest on the first part of the course when we are going through tunnels. I wore a vest that was as tight I could find and gave it to my support car the second I was out of the last tunnel, but most of the people rode with over-sized vest and 20 km longer then they needed to (that was a more practical drop off point for the supporters). That observation, combined with all the horrible upright riding positions you see in a normal IM, is the evidence that aerodynamics is not on the top priority list of most of the triathletes.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

That explains everything. I am used to the term shoe cover for that.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

Hi Jim,

Very interesting reading your results on shoe covers / booties ! Can the same happen with gloves ?

For the Tri Octane suite, we discussed it on another topic but for me the upper body material is not elastic enough and then I don't run well in it. So any time made with the suit on the bike is lost in the run !
Have you ever had an athlete tested with the Skinfit suit + shoe cover combo : this one. I haven't got one yet, but I did try it on and the material seems a lot more flexible than the Octane material is.

How much of a difference do you see from adding the arms on a high end tri-suit... meaning if you take the fastest sleeveless tri suit and compare it to the fastest tri suit with sleeves ? Also curious about 1 piece VS 2 pieces suits, if you take the compare the same model tri suit in 1 piece and in 2 pieces ???

I definitely need to get in touch with you and stop by for some testing time with you next time I'll be in the US !!!

EDIT : I saw on your facebook you tested the Skinfit suit at least once with a pro ;-)

Let me test everyone's attention span...

Position is obviously where an athlete can find the most significant gains, but it's also important because it effects virtually everything else.

• Your position will effect how a helmet may, or may not, work for you.
• Your position will effect how clothing fits you.
• Your position will effect the front end of the bike; not only with the setup to attain your position, but also how your body interacts with the airflow around the equipment.

To worry about any other item on the list (wheels/tires would be the exception) is, for the most part, a waste of time until your position is dialed biomechanically and aerodynamically. And, let me tell you, you can really go deep here; the complexities can drive you mad, and I'm sure my wife could present an argument that they've already taken me down the road to being a window-licker on the short bus (I know that's so very wrong - I'm sure I've insulted someone). Let me give you an example (of the complexities, not my mental state):


Let's get back to shoes covers (booties). We're going to have to assume a few things with this scenario, so just roll with me on this for the sake of making my point, and don't get too picky.

Let's say an athlete tests a set of shoe covers and sees a decrease in CdA. For the next run, I decide I want to lower the athlete's seat position by 1cm because i believe there's too much knee extension at dead bottom center. Let's assume I'm able to keep all else equal by adjusting for drop, reach, etc. - heck, I'll even say we changed crank length to normalize for flexion of the knee at the top of the pedal stroke. In fact, we'll suspend belief for a moment and state that the only change resulting from the saddle height adjustment was the knee angle AND the angle of the foot at dead bottom center, which measured a drop in the heel of about 3 degrees (not uncommon). We conduct our next run and see that CdA has risen. Disappoinment. Why would it get worse of all else was equal? Well, I could make an argument that the increased drag was a result of the change in foot angle and, therefore, a change in how the shoe covers fit. Could a simple change in foot angle result in an increase (or decrease) in CdA? Certainly, we see the smallest of seemingly innocuous adjustments have an effect on CdA all the time.

My point is this. Change your position, and you change how you interact with your bike, clothing, helmet, etc. If we were to create a true hierarchy for aero, it might look something like this:

1. Position
2. Position
3. Position
4. Position
5. Position
6. Clothing
7. Helmet or wheels/tires
8. Helmet or wheels/tires
9. Clean front end (this could include aero bars, which may result in moving up this list quite dramatically depending on initial setup)
10. Hydration/Food setup
11. Frame

Dial in the position first, and don't make the mistake of assuming lower is always better. Once complete, you'll get better results testing everything and anything you want to put on the list.


Look, I could answer questions all day long about which skin suit is quicker than another, which is the faster bta setup; have I tested this, have I tested that. I get it, the information is addictive. In the end, and yes I know it gets old hearing it, but in the end it's all very personal. Your result may or, really, certainly WILL vary. I hope this helps.

---

Jim Manton / ERO Sports

Long ago one of my professors described the feudal system like this: "First, you have royalty: Kings, dukes, earls, barons. Then you have wealthy merchants. Then freemen. Then there's nothing. There's nothing; and yet a third time, there's nothing. Then you have the serfs."

I know at IM races you're not allowed to have your shoulders covered for a non-wetsuit swim anyway. I'm would imagine USAT would have a similar rule, but I'm not sure.

I think it could be argued that an area we forget when we talk about drag is body shape rather than body position[/img]. Ten, five or even two pounds of body fat is certainly bigger than most components being discussed. If you took a look at what ten pounds of fat looks like, it's pretty huge.....the wind would see it all. I have no data, but I think most of us would reduce our cda more by losing five pounds in comparison to new booties.

Getting fatter often/sometimes reduces drag.

WEIRD

However from a triathlon perspective yes, losing 5lbs would gain you a lot speed...on the run..for many people.

But, you can lose 5lbs *and* slam that stem.

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

This is an excellent point and its come up a few times with elites looking primarily at Kona.

A suit like the Tri Octane might save 4 minutes over an athlete's normal clothing setup, but taking the time to change into it in T1 will eat up some of that advantage, lets say half. Okay, well, you're still two minutes faster overall, right? Not really. While you're spending the extra time in transition, your fellow competitors are rolling up the road ahead of you, so now you're playing catch up.

An elite would prefer to skip all of that because, for them, they don't see this as a means to get ahead of everyone by two minutes, they see it as a way to use less energy to stay with the group. Mentally, coming out of transition a few minutes later than everyone else is defeating and not worth the extra energy they'd use catching up early on in the bike leg.

Does "staying with the group" equate to staying in the draft, even at legal distances? Of course it does. That's the reality - especially at Kona. It's all about economy of effort 'cause we all know you win it on the run.

Poor swimmer? That's a different story. Now it might be worth the extra time because it will be easier, over the entire course, to reel in the group ahead. So, for instance, if Heather Jackson switches to Ironman distance she and I are having this discussion because she gives up significant time in the swim. For someone like her, the benefit is important.

---

Jim Manton / ERO Sports

I might argue that it depends where the fat is coming off and where the muscle is put on. Big shoulders create a lot of drag in aero. Then again, at 6'2", 230'ish, I'm pretty sure my CdA would decrease dramatically if I were to drop down to racing weight because, trust me, it ain't muscle that's causing that weight! :-)

---

Jim Manton / ERO Sports

OK - you have my attention.

A tri suit with sleeves? Wouldn't that suck, royal, during the swim??
I made that mistake, once - once.
Wore a LG top (supposedly Tri) with sleeves for Timberman, and it chafed the ever-livin' F out of my arms and pits.

---

float , hammer , and jog

interesting, my pits chafe more if I don't wear sleeves...

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Body glide on the lats*. Problem solved.

* from mid-tricep, to the bottom of the lats, on the outside edge (not like deodorant)

Your current solution, of not racing tris at all, probably works well too. ;-)

---

float , hammer , and jog

A suit like the Tri Octane might save 4 minutes over an athlete's normal clothing setup, but taking the time to change into it in T1 will eat up some of that advantage, lets say half. Okay, well, you're still two minutes faster overall, right? Not really. While you're spending the extra time in transition, your fellow competitors are rolling up the road ahead of you, so now you're playing catch up.

An elite would prefer to skip all of that because, for them, they don't see this as a means to get ahead of everyone by two minutes, they see it as a way to use less energy to stay with the group. Mentally, coming out of transition a few minutes later than everyone else is defeating and not worth the extra energy they'd use catching up early on in the bike leg//

I'll agree with the tactics that are in play for the pros here but I will challenge you on the 4 minutes of savings with a different suit. One thing that gets left out of the discussion very often is what are you comparing against. I know you said what you tested against but that is not what the pros use as an alternative. Take a look at what ironman pros at the front are using and now we can make a fair comparison. This happens in swimming a lot, how much the swim skin gives you. Well it is a lot if you compare it against an unshaved person in a training suit. Same for wheels, if you are comparing against a 36 spoke cross 3 flat rim, you get big numbers. But no one uses those so it is not really a good test. What you need to look at is the minute differences between what you think is best against what athletes actually use in race situations. I do not believe that any thing you can wear as a suit will give 4 minutes over a very tight fitting tri suit.

I agree with you sentiment about body position affecting everything down the line though. Behind the seat aero bottle holders, great until you actually have to take a drink from them. Lots of stuff to think about..

Its not just tight fit; that's only part of the equation. It's covering the skin, which happens to be a very poor surface aerodynamically. Beyond that, you texture the fabric so it acts as a boundary layer trip. Most tri suits are sleeveless and expose the shoulders and part of the back. That slows an athlete down. Cover the shoulders and upper arms, and you'll go faster.

Crowie, Dibens, Cave, Joyce, Mckenzie, Jackson, and more have been here in the past few months. We ARE testing against what they're wearing, and numbers don't lie; they are who we get the numbers from. Call around, many manufacturers are working on sleeved kits right now based on our testing and results (okay, they may not admit it). I'm just not convinced its worth the extra time in transition for a non-wetsuit legal race, though I'm hoping to test something this week that might change everything.

---

Jim Manton / ERO Sports

Getting fatter often/sometimes reduces drag.

Rounder shapes! I suspect that a big beer gut would be quite good for aero if you could figure out how to get low and still pedal.

I've occasionally wondered whether zip on sleeves could be designed to be fast.

I wonder about these:

http://www.desotosport.com/product/CW

---

Jim Manton / ERO Sports

I'm actually on the market for a new suit and was looking at the Octane (based on this thread) and also the Skinfit model which appears to go down the arms and has longer legs...can we expect all companies to starting heading down this path? Outside of non-wetsuit swims, there is really no reason not to wear something like that if it doesn't have too large of an effect on the run? Does this also explain the testing on someone's blog that compression socks tested the fastest of all race kits?

We ARE testing against what they're wearing, and numbers don't lie///

I don't doubt that your numbers don't lie, unfortunately we do not race in a tunnel. Personally if i were racing i would put on some sleeves, but that takes just a couple seconds, so not a big factor in missing the train on the bike. My point is that what material is it that makes you so fast but also won't cook you on the bike? Also keep in mind that for most of the race you are in a crosswind, so the numbers you get and what are really available are going to be different.


I applaud what you are doing and I'm sure at some point it will be a benefit to the athletes. Like we have both said, tactically it won't make sense if it takes too long to make the change. Riding 10m behind a rider has to be worth waaay more than the supposed 4 minutes for a new suit. But some quick arms with a breathable material is certainly a viable option. I figure i could put on the clumped arms in under 8 seconds and then do the roll down and up on the move at full speed, so not too much to catch up..

That's not a beer gut, it's a "belly fairing" ;-)

---

http://bikeblather.blogspot.com/

it's too bad this wasn't a secret for a little longer...

---

Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

“You are experiencing the criminal coverup of a foreign backed fascist hostile takeover of a mafia shakedown of an authoritarian religious slow motion coup. Persuade people to vote for Democracy.”

Interesting.

My own tests with otherwise tight jerseys with the zipper either up at the neck or just part-way down make me think that if air can find a way in it will. That makes me wonder whether that's a robust design (robust in the sense of "it may be good if it's tight and smooth but if you get a gap somewhere will it be disastrous?").

Which is why we don't test in a tunnel! :-)

---

Jim Manton / ERO Sports

http://www.youtube.com/watch?v=E0PIdWdw15U

so tired of this "in the real world" meme

---

Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

“You are experiencing the criminal coverup of a foreign backed fascist hostile takeover of a mafia shakedown of an authoritarian religious slow motion coup. Persuade people to vote for Democracy.”

Next up: "aero only matters if you're already fast."

Followed by "all aero bets are off in a sprint due to the side to side motion of the bikes" :-/

---

http://bikeblather.blogspot.com/

Anyone think a De Soto long sleeve skin cooler would be faster than a normal Tri top.

Am thinking about wearing the long sleeve tomorrow in Canada after reading this. .

http://www.desotosport.com/product/LST1

Whooo Hooo! I bought one on sale at TriSports! Haven't raced in it yet. I really had no idea that it was fast. Bought it because it was on sale and looked cool. A little weird that it has sleeves, but I guess that's the whole point.

gonna' take it out for its first race in a few weeks.

You just need to pump up your tyres more.

I was hoping to see this as those of us that race in team issued kits are very limited in options...well, not limited, we have one...lol

---

-------------------------------
I'm faster in Kilometers!
Wattie Ink Triathlon Team
Powered by Accelerate 3

I understand the potential aero benefit of longer sleeves on the bike but what is the benefit for the swim (I'm assuming this is the reason for the shoulder rule)? Is it compression of the body so it is smaller in the water or is their something else?

 

Fortunately, the tunnel and real world agree as far as drag goes. So as long as the skinsuit doesn't tear your balls up....

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

The shoulder rule may be purely an aesthetic one and/or so that your race number is visible

Pro cycling has a rule that you MUST have sleeves, just aesthetic and possibly to increase sponsor area

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

You might not, but some do:

http://www.youtube.com/...ed&v=pWjJUy6tCAI

http://road.cc/...derground-big-prizes

Rules for triathlon clothing are, I believe, originally inherited from FINA rules. If not wetsuit legal, no clothing beyond shoulders or knees - basically, the idea is to prevent a full-blown speedsuit war with swimskins that cover the entire body.

---

ZONE3 - We Last Longer

You're right, Jack -- wind tunnels isolate aerodynamic forces very well. I'm sure no one's implying otherwise.

The best practice is to use all three legs of the stool: CFD, wind tunnel, and aero field testing. I think most of the top manufacturers have already embraced this to one degree or another. Each one has its own strengths and weaknesses.

---

AndyF
bike geek

Hey listen everyone, i think wind tunnel testing is the tits. And just like pool testing for wetsuits and skins it is the best possible place to eliminate as much noise as you can to get any meaningful results. I think tunnel tests should be done on all this new stuff. My point is that i'm very leery when someone says this or that will take 4 minutes or 10 minutes off your bike times. This has been going on since the first bike went into the tunnel. If you add up all the savings that aero shit is supposed to give you, then guys should be well under 4 hours in hawaii. It has just never added up so i remain skeptical on outrageous claims. My only point to bringing up real world conditions is that i believe they are what put the crimp into these supposed possible gains. So many variables to consider, and too many to control, so that is why you really don't get 8 or whatever minutes with an aero helmet. And i can guarantee you that if i speed up just a bit every time the moto comes by to do some filming, that will trump everything you could throw at some group of aero do dads. Not to say you should not have all this stuff, because it does not negate you from upping your cadence every time a truck or car goes by, and even gets you going a tiny bit faster.

But it is all good, remember when swim skins were giving 15 even 20 seconds a 100?? I'm most of the way through my tests and 3 seconds has been the best thus far, and that is against me unshaved and with training jammers for the control. All these things seem to swing like a pendulum, eventually finding the real bottom where the truth sits..

monty, expressing something in minutes is akin to expressing it in grams of drag. It's simply a unit of measure, not a value judgement. The stipulation is "all things being equal".


Well, that's where the "all things being equal" comes in. Some changes are incompatible with others. You can't stack them all up. It's not a purely additive sum.

But in general, wind tunnel testing has pretty much fulfilled its promise. I'll leave you with the quote that my friend, Jim Martin, often uses:

---

AndyF
bike geek

I have been in the wind tunnel and wound the results quit similar to reality. I tested my Specialized Shiv with TT-helmet against a Baum road bike with a road helmet. The theoretical difference in the tunnel would imply a massive 6,5 minutes difference over 50 k, and when I tested it outside (with a Powertap powermeter with 300 watts in average on both) I ended up up with an average difference of 30 sek on a 5 k course which would have been 5 min over 50 k. The reason I think there is a 1,5 min error is that the best TT-position (which was the base of my calulations) was with my head really low, and not a position I could hold 100 % of the time. Every once in a while I had to look up and watch out for holes in the road, cars etc. Therefor my aerodynamic drag in the tunnel (CdA of 0,208) was a bit lower than I could do on a rolling course with some turns.

At least my little experience with the tunnel is that is is a very good and precise way to find out what actually is aero for you, and what is not.

But I agree that is seems odd with all the aerodynamic improvements that the time have not been reduced more, but I think that often the companies are exaggerating their claimed benefits. Also we must not forget that it needs massive reduction in aerodynamic drag to save a lot of time. I reduced my drag with about 10 %, which is a lot, but that only gives me about a 7 minutes theoretical saving over 180 k, and I do not think the best triathletes get a 10 % overall drag reduction that often.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

btw, if skin is that much slower than aero fabric/textile, why does not Bradley Wiggens wear a long sleeve og gloves? I would guess that Bradley Wiggens olympic setup is one of the most tested setups in the world of cycling. Then again, he is riding with around bottle.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

$$ trump Aero.

How much do you think teams get paid to ride with the Gatorade bottle?

I understand that a well located mirror will save lots of drag in a race situation.

At least my little experience with the tunnel is that is is a very good and precise way to find out what actually is aero for you, and what is not.

And it sounds like you confirmed that field testing is also a good way to find out what is aero...

Gatorade uses a lot of money of on marketing so I understand that they will use a product that is not the best regarding pure performance, you would think that they would make a aerodynamic bottle with Gatorade on.

But Wiggens rides with a HED 3-spoke wheel and Osymetric chainrings (changed to round ones now) even if that is not on Team Sky's sponsorlist, so obviously they have drawn the "$$ trump Aero"-line somewhere.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

Field testing have unfortunately a too much margin of error to be a good way to find out what is error. With my Shiv I had 30 % less drag than on the roadbike, which is massive. That translated in to 30 sec difference on 5 k course, but I had 3 sec differance on each run with identical set up. It I would make changes which is smaller, like changing from a TT-helmet to a road helmet, it would be much more difficult to see. And if you do smaller changes it might be impossible to conclude anything on field testing (if not in a velodrom like the ERO does).

In the wind tunnel I could instantly see the impact on the smallest changes since I had my drag projected in front of me in real-time while I was pedaling.

---

http://www.triallan.com
Ambassador of:
Quintana Roo - https://quintanarootri.com
Bioracer
Precision Fuel & Hydration

this

Nice link.

Obviously fit will be dependent on your given individual body, but what are some skin suits that would be worth looking at?

Likewise, what shoe cover do you personally use?

Not always.

I believe the UCI restricts the shape and size of aero bottles - quite a few of the popular models are UCI-illegal these days. Also, with the special cages, it might cost Wiggo more time being out of the aerobar and fiddling with the bottle than he'd save with an aero shape.

---

ZONE3 - We Last Longer

In the wind tunnel I could instantly see the impact on the smallest changes since I had my drag projected in front of me in real-time while I was pedaling.

It is good for that... which would be subtle changes in positioning.

A few years ago I analyzed the raw data on someone's wind tunnel test (a respected tunnel and operator) and was not impressed. The random variance on drag was ~ 2% when doing a yaw sweep and returning to zero. And conclusions were made on differences that were much smaller than this... based on a single run.

I don't know why... maybe small changes in position or something else. I know that I have a huge range even with all the contact points fixed depending on how I hold my head and shoulders.

So like field testing, I think you want to spend a lot of time in the tunnel if you are looking at changing small things. Test each configuration multiple times, switch back and forth, etc.

Easily the best post in this thread. Great observations and advice.

---

Jim Manton / ERO Sports

Well, was this a constant speed yaw sweep or do you mean "test at some non-zero yaw then move the table back to zero yaw, let the flow stabilize, and then test again at zero yaw" and see a 2% difference in zero-yaw drag?

The later.

I was told by someone who had a lot of experience at San Diego (it wasn't that tunnel), that 1% was what they would typically see. And I'm sure it varies a lot with the person... if it is indeed mostly a small positional change that was causing it.

I wasn't even thinking of your velodrome testing. I can definitely believe that you get results that are as consistent as a good tunnel, with the only limitation that can't look at yaw effects. On the other hand you do get the "power to spin the wheels" term included which is missing from tunnel tests.

That's interesting. I knew that same tunnel same rider same setup across sessions could typically be 1% different but I hadn't realized that you could see 2% within a session. That sounds large.

One of the things I've played with in field testing is a better way to get the standard error for the estimate of the CdA.

Hello rruff and All,

There is still quite a lot of room for aero improvement in conventional triangular frame bicycles/riders/equipment in triathlon though less in the more strict UCI depending on how rules continue to evolve.

I do agree with Monty that data gleaned in a pristine wind tunnel or testing protocol when used for a sales presentation (yes my data too) very likely shows better results than the data that would be gathered when in a race, outdoors, gusty wind, hot humid day, with dust and sweat in your eyes, in traffic, with your jersey riding up, your left leg hurts, there is a bee in your helmet, you missed the last feed station, and your competition is somewhere up ahead of you. However it is standardized data and can be compared to other standardized data ........... but as Monty says ......... should be taken with a grain of salt when applied in a race environment.



While not a triangular frame .......... even in HPV aerodynamics make a difference ...... 82+ mph ............... :)

I expect market forces in cycling will continue to cause the various rules to be modified creating obsolete equipment and procedures requiring periodic replacements.

If we were looking for the true ideal .......... 'it is the cyclist - not the cycle' meme ........... we would all ride the same device with the same position, clothing, etc.

I think I like the current evolving equipment environment better than a static one even though is involves more thought and time that could be better spent on training.

Cheers,

Neal

+1 mph Faster

I think I would have to disagree with this statement...it might depend on the protocol/experimenter ;-)

http://bikeblather.blogspot.com/...ng-chung-method.html (limit of detection apparently less than ~1.5W at race speeds)


http://www.trainingandracingwithapowermeter.com/...aerodynamicists.html (also limit of detection apparently less than ~1.5W at race speeds)

---

http://bikeblather.blogspot.com/

Ya... even 1% is pretty big. When you think about the drag on a set of wheels being 10% of the total, that represents a 10% variance on wheels alone... if you are comparing one set to another with no other changes. The same goes for a lot of other aspects.

The people doing the testing are in a tough position, because it is much easier to sell the service if you tell someone they can come in and test 20 setups in 2 hrs. If you have a client who is not able to hold consistent positions, you don't really want to say "sorry, none of your data are good... that will be $2k please". Easier to just give them the numbers... everyone is happier. But in reality you need to test that baseline over and over again, and the variation establishes the accuracy of your results. It will give you an idea of how many times you need to test each configuration to factor small differences, too. It's tedious, time consuming... and expensive unless you are doing field testing on your own... and even then you have to figure what your extra time is worth.

The reason I liked your post was that you touched on two key points.

First, you're correct, when you see small changes in drag, it's important to know if they're within your margin of error. Yes, we see very consistent results, but we also understand that a small, unintentional, position change by a rider can effect CdA on any particular test. We're able to detect small changes in hand position, so we certainly have to understand results must be questioned and verified.

This, of course, leads to your second point, which was equally correct. Test and test again. If the results are close, it's very important to test back and forth. Get a bigger picture and see if the results are consistent. I actually find myself re-testing for validity even when the results are dramatic, or really, because the results are so dramatic. Sometimes it just seems to good to be true, and I'm compelled to verify. It's just good science; at least that's my intention. :-)

---

Jim Manton / ERO Sports

FTFY.

Can you elaborate? & then why are front wheels generally lower profile than rear/disc wheels? And then why not a deeper front wheel? Not trying to argue, just to understand. Thx.

---

_____________________________________
What are you people, on dope?

—Mr. Hand

I'm not the expert. I've just been made to understand -- mostly from reading here -- that the front wheel plays a much larger role in aerodynamics than the rear. Perhaps Tom A. or someone else who lives in this world can elaborate (or correct me). The way I understand it, the front wheel is so important because it's the first thing the air hits. The air is pristine at that point. However air is quite a bit "dirtier" by the time that it reaches the rear wheel so the savings are reduced.

Again, purely my rudimentary understanding.

On modern aero frames, the rear wheel is shielded so the drag of the rear wheel is much less tham the front wheel.

For the budget minded, getting the best performing front wheel and a disc cover rear makes the most sense.

Handling. The deeper you go on the front, the more skittish the bike can get in winds. One significant gust and you're no longer riding super fast, you're picking yourself up out of a ditch.

If I am not mistaken, I believe that bottle on the seat tube is more aero than bottle on the down tube.
I think I read this somewhere w/c is why I put my bottle on the seat tube -- it saves me 5.2789 secs on a 70.3.

Depends on the frame and type of bottle. Avoid round bottles if at all possible. A recent trip to A2 saw a round bottle on the seat tube of a Specialized Shiv cost more that 8 watts of drag (~80 grams). This convinced him to run the bladder which he felt like was a PIA to deal with.

---

---

Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

Hmmm, that's a pretty drastic exaggeration. I'm smaller than most, have ridden in terrible conditions and never been actually tossed from my bike or pushed off the road.

There were complete disc front wheels for road use and still are somewhat on the track indoors.

The issue is handling. If you've ridden a rim deeper than 90mm in a decent wind, you're spending plenty of effort/attention controlling the bike. With the recent design changes away from straight "V" rims (i.e. Zipp Firecrest), you can reduce the effect of side wind issues and at a less deep rim. Zipp claims the latest 808 is faster than the 1080 was.

So you've been running a disk on your front wheel? There's a reason why you hardly ever see that being done and it's not because of a "pretty drastic exaggeration".

the person you responded to wasn't really asking about discs, just generally why deeper on the rear. I agree its a matter of handling, but I think front wheel handling is pretty overblown. I did ride a set of H3s for a long time and they are considered to be pretty bad handlers as a set(disc rear seems to balance them). I even rode them in a raec with gusts up around 40mph. I never left my aerobars because of wind.

Girl who races in texas and louisiana races with a front disk from time to time.

Can't believe it is all that much worse than an 808.

I'd try it =)

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Perhaps I should have expressly mentioned "disc" in regards to the being blown of the road bit, but what I said still stands (and was repeated a few times).

It affects handling. I've been moved halfway across the road riding only 60mm wheels. I've also had gusts push me off the road on a few occasions where I was skirting the edge. It's not that uncommon.

I'd also be keen to give it a go on a calm day.

But I wouldn't do it on a windy/gusty day.

Hate to say I told you so, but...http://triathlon.competitor.com/...-from-castelli_83188

Trust me, this was developed very quickly. Probably started no earlier than May, I bet. I wonder how hard it would be to put the top on in T1 while you're wet? The sleeves might be a more realistic option.

---

Jim Manton / ERO Sports

I will buy one of those.
Like it!

@Jim, do you have an opinion about whether the Giro Selector helmet is generally faster with the shield or with sunglasses?

It's one of the very few helmets that tests faster with a shield. Very consistent in that regard.

---

Jim Manton / ERO Sports

Great info, thanks!

Last year at the Olympics too in the women's road TT, forget who- I think a Dutch girl.

Sorry Aussie:

http://london2012.olympics.com.au/...1E1-B17B005056A37760

Maurice

  
what about the LG vorttice (and its new replacement)? i run it with no shield, as i understood them to be slower.

also, thanks for your posts, very interesting.

No shield on the Vortice...same with the new P09 when it comes out.

---

Jim Manton / ERO Sports

---

---------------------------
''Sweeney - you can both crush your AG *and* cruise in dead last!! 😂 '' Murphy's Law

Fusion have been producing something like this for a little while see http://www.fusionsportsuk.co.uk/...ops/fusion-speed-top I have had one for the last year and found it to be very good. I wear it during the swim and then shed it in T2. Used it both at races where it has been on the cool side and it did help to keep me a bit warmer and also for Alpe d'Huez long course where it was very hot but regularly pouring water over it seemed to keep me cool and stopped me from burning. There is no way I would like to get it on in T1, I can't see how you would do this without towelling yourself dry completely. No idea how the Fusion one works out in terms of aerodynamics.

Steven

Side-note : Does anyone have any experience with the ice-packs from Fusion ? I don't function very well in hot weather, so this could be considered a great aid in my case. I only need to have enough of these available at the personal service-stations to "replace" them during a race to keep in full functional mode ;).

Sweet, double-discs! Don't see that often, but if the conditions are calm that is the ultimate wheel choice. They use double-discs all the time in track because there is no wind.

Jim - Kask Bambino w or w/out shield? And if without, with or without sunglasses?
thx!

I don't have a solid answer for you on that one. The Bambino's effectiveness is so position-dependent that it makes generalizations difficult. If I remember correctly, the results are mixed shield vs no shield.

---

Jim Manton / ERO Sports

Hi Jim and other experts, thank you all very much for this great thread!

I'm a typical age group triathlete, just did my first Ironman. I've always used standard road helmets up to this point (Bell Alchera currently), and I already have a tri bike and old (non-Firecrest) Zipp 404/808 wheels. I understand that position and clothing aside, the only meaningful place left to improve from an aero perspective is helmet.

I was super interested in picking up a Giro Air Attack, but right as I was about to buy one, a friend told me it would save far less time than a "real" aero helmet (something with tail). Since I seem to have found the experts, I have a few questions:

- is the Air Attack the new shiny? Do you agree it's not as good as a traditional aero helmet? Are there numbers on this? And is it significantly better with or without the shield? (I wear prescription cycling glasses, so I'll have glasses either way.)

- for us regular middle of the pack triathletes, what would you recommend for an aero helmet? The Rudy Project Wingspan is a popular helmet but how does it compare to others from an aero perspective and comfort etc? Since I'm slow, I'll be spending more time in it but also averaging a lower mph.

- do you have to keep your head up / aero tail down near your back for the aero helmets to be effective? Like, if my head angle is 30 or 40 degrees down, and the tail thus lifted up, have I now destroyed the aero of the helmet and would be better off with my regular vented bike bike helmet and/or the Air Attack (since it has no tail)?

Thank you in advance!

What do you think of Javellin Visor/No visor?

---

Ironman Certified Coach

Currently accepting limited number of new athletes

Has anyone ever tested something like a Skins or 2XU long sleeved compression top vs a tight fitting tri suit?. I have one of these and wondering whether it would save me much time in a HIM if I wear it under the wetsuit and use it for the bike leg.

Not on your list, but skin suits were tested to be one of the most aerodynamic improvements- even compared to just a regular cycling jersey

I think Castelli is making a new tri top that would cover the arms and be aero.

If you dont need tri specific then research the Catelli / San Remo its an excellent solution. Look for the 2013's it to go on sale soon. I got 2 last year at 50% off.

How would the San Remo work for a Tri. I was reading and it seems like a 2 piece stiched together so could be a best of both words.

Sorry i cant help you on how to use the normal San Remo for a tri but they are making a version thats tri specific (for cool weather) Info here.

I also saw that Castelli tri (top only) info here.

Saw those too. Jim@Ero has convinced me to go this route so just looking for what may work best. Right now, its Octane or bust but looking to see what's coming as well. Testing a Desoto here shortly for non wetsuit OWS.

 
Verdict in. Tried it out today in the pool. The Pearl Izumi Octane works fine on the swim (without a wetsuit over it). comfortable. The sleeves are very flat and skin tight. No problems. Not sure, but it might make me 1/2 to 1 second faster per hundred, as compared to lycra jammers. but maybe any tri suit that stretches over your upper body would do that. ??

Downsides:
1. probably a little warmer, given that it has sleeves, and
2. Takes a while to get off your shoulders if you intend to pull it down to pee. Doesn't come off like a sleeveless. Even a wetsuit is easier to pull off your arms than this thing. So- unless you pee on the bike and the run, any time savings will be lost in your undressing time.

I thought earlier in this thread it was mentioned that you can't have your shoulders covered in WTC swims. That would make using the Octane without a wetsuit illegal. The rep at the Skinfit booth mentioned the same things about the streamliner.

http://skinfitusa.com/...ri-suit-streamliner/

It does state it in the Athlet's Guid for Vegas "No fabric below the shoulder."

http://www.ironman.com/~/media/cd354c2426004f6b8033e69a34ff20df/70%203%20vegas%20ag%208%2029.pdf

Hmmm. Something I'll keep in mind if I ever do a WTC event

I thought the ERO test results were meant to remain confidential... ?

---

____________________________________

Are you ready to do an Ultraman? | How I calculate Ironman race fueling | Strength Training for Athletes |

that's funny. Other than the hydration setup, it's pretty much inversely proportional to cost. i.e. cheap things are much more beneficial than expensive things.

FWIW- I raced in my Pearl Izumi Octane today. Nice suit. Felt fast (whatever that means) during some headwind sections. Not as hot as I was expecting given that it was blaring sun and in the 80's on the run, so the In-r-cool fabric kinda' works. Not as cool as a white, tech running shirt tho'. Anyway- nice tri suit. And, I did well (for me).

I have the Attack (without shield) and Selector helmets and do feel the 'regular' TT helmet is more aero. Of course I have no proof, but it feels more aero. I used the Selector in several tri's this year (including a half iron) and I just don't feel wind on my head as much. I wish I had gotten the Attack with the shield, but I wanted a helmet to use on my road bike for my 'normal' rides and didn't want to look geeky.

Thanks for this. I used a Tri Octane suit in my last race based on the advice above and was very happy. No problems on run with it as well.

I pulled this out of one of the attached links.


The San Remo 3 is showing really fast and a big improvement over the version 2 which was said to be 10 - 15 watts @ 25mph. If there is only a 4 watt difference between that and the Body Paint wouldn't the comfort and improved cooling be worth it?

Giro Air Attack
vs.
Rudy Project Wingspan
vs.
Giro Selector w/ Visor

Considerations: aero, comfort, heat, race, regular riding.
Thoughts?

---

/Howie Nordström

Too many considerations.

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Giro Attack looks like more of a training helmet than HIM or IM helmet. Yes?

The Wingspan and Selector OTOH are racing helmets. Are they similarly aero--especially if one's head isn't ideally centered? The Selector is 'simple' (no front vents) but is it hot?

---

/Howie Nordström

Not sure if you know this but Fusion has launched in the US. http://www.fusionsportsusa.com/ and since we are trying to launch it and get it in the hands of a few people we are doing a discount code of FusionUSST20 which will get you 20% off anything you order for shipping in the US. If you have any questions about the product don't hesitate to contact me chance@fusionsportus.com

---

Chance Regina
President
AVC Enterprises

I know this is old, but I'd sure like to know, which would you guess is faster for a typical age grouper with a slowtwitch approved position, PI octane, or Body Paint 2.0? Do you recall any issues with loose sleeves on the octane?
Thanks!

It's a little apples to oranges as the Octane is a tri suit while the Body Paint is a cycling-only skin suit. The Body Paint will certainly be faster by a decent amount, but good luck swimming or running in it! :-)

---

Jim Manton / ERO Sports

I used the PI Octane in a recent IM, under a sleeveless wetsuit, and there were no issues with loose sleeves. They're very tight and reach almost to the elbows.

---

<The Dew Abides>

Hello,

I have found this a very interesting thread. I am a new triathlete riding a CAAD10 road bike in sprint distance races. I have a pretty decent shot at making the worlds team in the sprint distance race in august. This has become my primary goal. Eventually I would be interested in racing 70.3's but iron distance does not appeal to me at all. Back to my main question. The guys at my bike shop don't think being aero (and having an aero helmet) will have much of an impact on such short race. I really have no way of knowing because I am so new to this.

I am pretty sure I am not racing in an aero set up at all. So what is my best course of action?? I intend on working on the engine regardless.

1. New bike fit on a road bike and invest in race wheels?

2. New tribike?

3.???

Any feedback is greatly appreciated!!!

I have both the octane and the body paint 2.0 skin suit. You can't swim in the body paint and it would take a long time to change into it in T1. and you can't run in it. The octane is designed for tri so you can do all 3 sports in it, but if you want to change in or out of it, it's quicker than the body paint. If you get the right size it's very tight everywhere, no loose sleeves or wrinkles and it's cool. But if I was doing a cycling TT I'd wear the body paint.

---

____________________________________

Are you ready to do an Ultraman? | How I calculate Ironman race fueling | Strength Training for Athletes |

for a sprint I wouldn't really bother (personally).
for a 70.3 being aero makes a much bigger difference, and the biggest gains will most likely come from your body position, so getting a good fitting tri bike might be a good idea if doing well at the 70.3 distance (or even olympic distance) is your goal.

---

____________________________________

Are you ready to do an Ultraman? | How I calculate Ironman race fueling | Strength Training for Athletes |

For what it's worth from an age grouper, 215 lbs, doing tri's for 5 years that shoots for 20+ on sprint. I have a Rudy Wingspan. When I first got it, I rode my local race route consisting of a 14 mile rectangle (5, 2, 5, 2) 1 week after riding the same route. 45 sec improvement. I thought the 2nd run was slightly windier and my legs tired. Highly doubt I can give the helmet credit for the whole improvement, but 1 week of additional fitness would have maybe added 5 sec. An aero helmet is cheap free speed, although if not riding aero, highly doubt you'd get the same advantage. I haven't ridden a decent road bike to know the difference between one and a TT bike. If it's a hilly course, could possibly be a push, but I can't get up hills worth a d&mn. On a flat course, I would imagine a TT bike faster, but I'll let an expert answer that.

The difference is approximately the same in terms of how it will affect your placing no matter the distance.

---

---

Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

A common misconception. In fact, in a short race, you stand to gain more with aerodynamic improvements than in a long race. You won't save as much time in absolute terms (i.e. minutes) in a short race compared to a long one, but you'll save more time in relative terms (i.e. percent of bike split). The reason for this is that power to overcome aerodynamic drag is proportional to speed cubed, making this term relatively more important at the higher speeds encountered in shorter races. The relative gains are what really matter. In a shorter race, there will be smaller time differentials deciding the results.

Your best course of action is probably to get a tri bike. Most people can achieve their optimal tri position (for aerodynamics, power and comfort) more easily on a tri bike than on a road bike due to differences in geometry. But not always. A small minority of people with very upright positions or freakish proportions may be better served by a road bike. Your position should be your #1 priority, as per Jim@EROsports' first post in this thread. Ideally, you would buy a tri bike and have enough left in the budget for a fit as well.

---

CodyBeals.com | Instagram | TikTok
ASICS | Ventum | Martin's | HED | VARLO | Shimano | 4iiii | Keystone Communications

I have a big problem with that statement. It doesn't matter how long, 100 yards or 100 miles, the race is, aero is still aero. It's simple physics. Lower drag = higher speed for a given power. There is no less reason to be an a super aero setup during a sprint than there is during an Ironman. You will still have the same reduction of drag.

Now what they may have been trying to get at, but in the wrong manner, is that if the course is EXTREMELY technical or your tt bike handling skills are not up to par, cornering could be slower when riding your tt bike. Typically sprint courses will have more turns per mile than an Ironman, which often include extremely long straights or sections with no turns.

ETA: Looks like Cody beat me to it.

The CAAD10 is a great starter bike to build on and I would suggest adding some low hanging fruit to it.

Clip on aerobars, fast forward seatpost, Xlabs BTA, LG Course or Specialized Evade helmet, GP400 tires w/latex tubes and fit.

Ride the trainer using sufferfest and trainer road over the winter and focus on increasing your ftp and making you pedal stroke more efficient.

Power meter would be nice but you can add that later.

Beating a dead horse here but had another question on long sleeves ...

How important is fabric? Would a custom made tri-suit (w/elbow length sleeves) - from a company like Nimblewear - achieve the desired effect? Or would I be better to go with the PI Octane?

Thanks.

The type of fabric used is extremely important. Remember, your skin is "skin tight" but, unfortunately, the surface material isn't very good for aerodynamic purposes. All else being equal, long sleeves are better than short.

There's no such thing as beating a dead horse when it comes to aero! There are suits faster than the Octane on their way. Tri suits will evolve much further this year.

---

Jim Manton / ERO Sports

Jim, don't leave us haning like that ; )

[/quote]

The type of fabric used is extremely important. Remember, your skin is "skin tight" but, unfortunately, the surface material isn't very good for aerodynamic purposes. All else being equal, long sleeves are better than short.

There's no such thing as beating a dead horse when it comes to aero! There are suits faster than the Octane on their way. Tri suits will evolve much further this year.[/quote]
Is the Skinfit Streamliner one those faster suits you were talking about?

Jim, between the Octane, the new Castelli Body Paint SR Tri Suit SS, and Champion Apex, any thoughts?

I have been looking at this as well and this is what I have found. It's not only the Octane, the Castelli Body Paint SR Tri suit SS, and Champion Systems. Like previously mentioned, there is the Skinfit suit. What about the Castelli Stealth T1 long sleeve. Plus, Jim was really wanting to test the DeSoto Coolwings as well. If they tested well, that would be the best bang for the buck. But, who knows who else is trying to jump in the aero tri suit ring?

Looking at the information, however...As Heath Dotson mentioned in their Aero Camp, we know the Octane tests well, if worn correctly, meaning tight.
http://forum.slowtwitch.com/...Aero_Camp__P4943130/
Castelli says they have tested in the wind tunnel with 24w or so savings in Watts for the SS suit. More for a long sleeve suit.
http://issuu.com/...ng?e=2137948/6588117
Skinfit talks about wind tunnel testing but no numbers to come by.
http://skinfitusa.com/...ri-suit-streamliner/
Then the Champion Systems and Coolwings with just possibilities but no data released, yet. Again, aerodynamics is individual. But, it would be nice to know a general frame work.

Anyone else find any other information? New line of clothing? Aero testing?

No results unfortunately but Fusion I believe have a similar short sleeved trisuit in the pipeline.

I've used their gear for a while now and it's good quality stuff so I'll be interested to see how that tests if it appears.

I've heard this suit is pretty aero



Sorry, I couldn't resist.

---

"4 wheels move the body, 2 wheels move the soul"

It was only a matter of time before that happened.

I like the idea of not worrying about putting anything on (sleeves) so I narrowed down to the three but like the above haven't found much.

right now, I'm leaning whatever one I can find at the best price until Jim (or someone) provides some guidance. I think under armour is out :)

Ya, that's out there but the big talk during the Olympics was how fast those suits tested against the other suits. But.....I wonder if that means UA is no longer in the aero garment discussion :). \pink?

I'll go with 3 & 2

A tri bike will save you a fair bit of time vs a road bike if it fits right.
I'd argue (correctly I might add) that you can buy all the aero helmets, skin suits fancy aero water bottles but unless you test each of those in a wind tunnel/velodrome/field testing your aero helmet may be saving you :20 while another aero helmet may save you 2 min. An aero bottle may or may not be faster than a round bottle, and I've seen the PI Octane cost end up being slower than regular race kit on more than 1 person.

If I wasn't going to get tested I'd buy on trends. I'd choose the equipment that made the majority of people the fastest or tested in the top 1-3 pieces of equipment for a large swath of people. Might not be the fastest but probably not the worst either.

---

Brian Stover USAT LII
Accelerate3 Coaching
Insta

I've been wondering the same thing; however, I did find some information explaining the difference between the Castelli Tri Free and Body Paint suits based on this link: http://forum.castelli-cycling.com/...i-free-or-body-paint, which states:

"Free is best for overall aerodynamics (wind tunnel-tested aero fabric across mid-lowr back) and temperature regulation in hot-weather racing environments (lighter-gauge fabrics in garment) (we have to assume, in this day & age, that the vast majority of athletes race with either a speedskin or wetsuit over their trisuit, so I place a much higher priority on aerodynamics vs. hydro, as the suit will be covered in the water anyway�). BP is best if you value the ultimate combination in fit, comfort and muscle support (minimal seams, higher-gauge fabric which provides a great blend of muscular support/compression while not being overly restrictive)".

I recently ordered and received the Octane and Castelli Free so I could compare them in terms of fit and material. In terms of fit, there's a big difference in the sleeves. The Castelli Free sleeves stop in the middle of your bicep and are a lot tighter. The Octane sleeves covers more skin and goes down to your elbow. There is also more flexibility in the armpit area for swimming (although not sure you would tell in a wetsuit?). The downside or tradeoff for the added flexibility is the Octane sleeves are looser and have the potential for wrinkles if your arms look like pipe cleaners (note, the rest of the Octane fits tight). The fabric on the Octane is consistent throughout the entire suit, while the Castelli has different fabric on the sleeves vs. the aero material on the mid-lower back. Lastly, I ordered a small in both (I'm 5'8" 140lbs). The Castelli Free is definitely a tighter fitting suit and I see why some people order a size up.

Do you think that the Octane suit could be tailored to fit around the arms without destroying the fabric? I have normal sized arms (I don't swim).

If I remember correctly, Jim@ERO mentioned that custom aero clothing is probably the next big thing, so I think the answer is yes.

For a comparison, my arms measure 11" (across the bicep). Based on my Octane fit, I think arms < 11" would most likely have wrinkles and need tailoring, and/or a few trips to the weight room.

Ignore all that. 7.0 for an FTP and you can ride the beach cruiser to a sub 4 ironman bike split!

Jim,

Are you able to comment on when this year or anything we should have our eyes out for? I'm looking for a race kit for later this summer, so I can wait if it mes sense and there will be better options by July.

---

Shut up legs.

I am teetering on the edge of getting the SkinFit Streamliner.

Does anyone have a review on this sucker?

---

http://www.athlinks.com/athletes/208730390

Don't specialize claim the greatest saving of all is the cheapest, shave your legs?

---

If you are sure you will fail, or convinced you will succeed, you are probably right.....

I think that hair on my legs offers more power as the weight will push the pedal faster.

Stubble will be less aero too.

So Ill stick with some hair.

---

http://www.athlinks.com/athletes/208730390

I'm thinking the same thing. Currently, I have a sleeveless top and a few pairs of their shorts. I love the quality and fit and thus am tempted to go with the streamliner. However, I can't find any reviews on it anywhere. I can't imagine it being low quality but wonder how hard it would be to pull up in T1?