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bostondrunk
11-26-2007, 05:32 AM
Well, a rep from a fairly well known Canadian company was in a LBS to talk about their TT bikes, and one thing he mentioned was that in an Ironman type of race position, an aero helmet can save 45 watts of power.........
I thought that was somewhat far fetched.......unless you are traveling at 100 miles per hour, no???
I'm thinking I need to get a Bell Meteor helmet and install it on the hood of my Jeep to save on gas....

Bruce K
11-26-2007, 06:15 AM
One of the guys in our club is freindly with the kid who runs the MIT low speed wind tunnel and does all the cycling work.

There is a significant amount of savings to be had from an aero helmet. I am not sure of the wattage numbers but the time savings over our 11 mile TT course was supposed to rival a disc rear wheel.

At one time there was also a significant difference in helmets available to the US market. With the growth of triathlons and the expansion of options, the variations have lessened quite a bit.

BK

William
11-26-2007, 07:38 AM
You know, I'm begining to think my helmet may not be so aero?

http://shop.rpg.net/images/uploaded/TVY15046lg.jpg




William ;)

J.Greene
11-26-2007, 07:43 AM
and one thing he mentioned was that in an Ironman type of race position, an aero helmet can save 45 watts of power.........


My source tells me Rivendell is working on a aero helmet that uses that 45 watts to power a full lightset and a rechargable camp stove.

JG

stevep
11-26-2007, 07:52 AM
45 watts... ok.

i wanna see the graph for a triathlete doing 22 mph for 6 hours
then one at 24 mph

would be curious how fast you had to be going to come up to 45 w
80 mph?

J.Greene
11-26-2007, 07:56 AM
45 watts... ok.

i wanna see the graph for a triathlete doing 22 mph for 6 hours
then one at 24 mph

would be curious how fast you had to be going to come up to 45 w
80 mph?

Stevep,

get on the bandwagon man. Between aero helmets and ceramic bearings we will reduce our dependence on foreign oil. It's big!

JG

bostondrunk
11-26-2007, 07:57 AM
You know, I'm begining to think my helmet may not be so aero?

http://shop.rpg.net/images/uploaded/TVY15046lg.jpg




William ;)

Does this involve a question about the speed/weight ratio of an African Swallow?!?! :)

bostondrunk
11-26-2007, 07:58 AM
There is a significant amount of savings to be had from an aero helmet. I am not sure of the wattage numbers but the time savings over our 11 mile TT course was supposed to rival a disc rear wheel.



I could believe that.....but there is no way a disc saves 45 watts either, IMHO..

stevep
11-26-2007, 08:17 AM
Stevep,

get on the bandwagon man. Between aero helmets and ceramic bearings we will reduce our dependence on foreign oil. It's big!

JG

yeah but you know what?
i bought williams aero helmet from him...he told he it was worth 125 bucks...
or it was 125 watts? i forget now... but it was 125 additional something...

could go from 18mph to 26 while training less that i do (not) now...
its hot though... unless used below 5 degrees f.

manet
11-26-2007, 08:44 AM
Does this involve a question about the speed/weight ratio of an African Swallow?!?! :)

http://www.intriguing.com/mp/_sounds/hg/velocity.wav

Acotts
11-26-2007, 09:22 AM
You know, I'm begining to think my helmet may not be so aero?

http://shop.rpg.net/images/uploaded/TVY15046lg.jpg




William ;)

Dude...thats flippin' sweet!!!! :beer:

SWorks4me
11-26-2007, 11:09 AM
race/ride with an aero helmet (TT style) and hit a long coasting down hill. keep your head straight, and watch your MPH, then tilt your head down and watch your MPH drop.

that long tail up in the air is the worst...watching TT's and seeing guys drop their head when they start to get tired...you just know they are dropping time.

ergott
11-26-2007, 11:17 AM
From what I understand, the helmet is the best aero gear once the position has been sorted. Wheels come in second to the helmet in aero TT gear. I think that number is compared to a regular helmet which in notably not aero. Simply putting plastic wrap on a regular helmet to close off the vents is a trick some have used as it is a big improvement since helmets are required these days. As stated above, all this is negated when the head is no where it should be so form is a must. Head down with those helmets not only eliminates the advantage, it creates a massive air dam.

ergott
11-26-2007, 11:20 AM
Other major savings can be found in number placement as well. The skin suit helps as well. You don't want all these sail-like protrusions on the body as that's where the air has the toughest time getting around. The wheels are easy in comparison.

swoop
11-26-2007, 11:23 AM
in my limited experience.. an aero helmet and a disc wheel instantly buy you time in a tt. the longer the tt the more time. its really true.

i never trust the numbers offered.... but it is buying yourself time and that makes it really valuable gear.

BigDaddySmooth
11-26-2007, 11:46 AM
A few years ago, the old Bicycling Guide mag did an aero comparison. They checked about 10 different "aero" components in a fairly good research-type setting (no wind tunnel evidently avail or too much scratch). Each item revealed a savings (for a 40K at 25mph or so) of a few seconds to 3+ minutes. The best item was <doink> aerobars. It saved something like 3m20secs. When all other items where used, the total saving was just under 4 minutes. So, the lesson learned is 80% of your time saving comes in the form of aerobars alone and there is a law of diminishing returns w/regards to the other components. In other words, the savings are not additive. I'm a gadget guy so for my next tri I'll have a HED 3-spoke front, fake disc in the rear, aerobars and an aero helmet. To get good though will require many hours at LT on the computrainer...

J.Greene
11-26-2007, 11:58 AM
To get good though will require many hours at LT on the computrainer...

Your bike shop will hate you if you keep talking like this.

JG

dutri42590
11-26-2007, 02:25 PM
Your bike shop will hate you if you keep talking like this.

JG
yes we do. you need ceramic bearings, aero wheels, aero helmet, skinsuit, and a new bike.
JPR

J.Greene
11-26-2007, 02:32 PM
yes we do. you need ceramic bearings, aero wheels, aero helmet, skinsuit, and a new bike.
JPR

Sell me a tail wind and a downhill...that's all I need to go fast.

JG

Bruce K
11-26-2007, 02:48 PM
To clarify....

Any discussion I have heard about skinsuits, helmets, discs, tri-blades, aerobars, etc. have all been in terms of time saved at a given speed over a set distance.

I have never heard it discussed in watts but it would make sense that if you get a good aero position and proper equipment it would take fewer watts to achieve the same speed.

BK

J.Greene
11-26-2007, 02:52 PM
ATMO, I can say that without a doubt. The average weekend warrior has more to gain by practicing pacing, or guaging effort than anything else in a TT. All of the little things are just distractions to completeing the task.

JG

dauwhe
11-26-2007, 03:11 PM
Two comments:

[1] So is it the goal of time trialists to go the same speed while using fewer watts? I thought the idea was to go faster! ;)

[2] I'm very skeptical of all these "measurements". For example, the 45 watt figure that started this thread sounds like B*****t. I poked around on analyticcycling.com, and 20% changes in drag coefficient would change power output by around 23 watts at world hour record speed (34mph).

I sometimes see these lists that say, "xxx saves 2 minutes, yyy saves 1 minute" and they sound like if you add them all up you'll finish your time trial before you start!

If I'm going to believe any of these figures, I want to know exactly what their test setup was. What equipment and positions did they use "before"? At what speeds? Measured how?

I suppose an aero helmet could save you 45 watts if it replaced a cowboy hat (and you were going fast enough).

Dave the skeptic

manet
11-26-2007, 03:11 PM
a penguin placed prone, pointed forward on head would rock the wind tunnel

wasfast
11-26-2007, 03:27 PM
Two comments:

[1] So is it the goal of time trialists to go the same speed while using fewer watts? I thought the idea was to go faster! ;)

I expect you're kidding but it's the same thing. Same speed with less effort or slightly faster with the same effort.

[2] I'm very skeptical of all these "measurements". For example, the 45 watt figure that started this thread sounds like B*****t. I poked around on analyticcycling.com, and 20% changes in drag coefficient would change power output by around 23 watts at world hour record speed (34mph).

With the advent of powermeters, you can do your own measurement in the real world.

J.Greene
11-26-2007, 03:33 PM
I expect you're kidding but it's the same thing. Same speed with less effort or slightly faster with the same effort.


wow! I have a new excuse for going slow. I'll just start telling people I have been using less energy than them :rolleyes:

JG

Fixed
11-26-2007, 03:37 PM
yes we do. you need ceramic bearings, aero wheels, aero helmet, skinsuit, and a new bike.
JPR
every season if not sooner
cheers imho

Grant McLean
11-26-2007, 03:39 PM
Well, a rep from a fairly well known Canadian company was in a LBS to talk about their TT bikes, and one thing he mentioned was that in an Ironman type of race position, an aero helmet can save 45 watts of power.........


That's metric french canadian watts based on maple syrup in your tires.

1 watt x 45 minute TT = 45 watts right?

-g

bostondrunk
11-26-2007, 06:08 PM
That's metric french canadian watts based on maple syrup in your tires.

1 watt x 45 minute TT = 45 watts right?

-g
No, I believe it is based on the Canadian Imperial Gallon, or something like that.

dutri42590
11-26-2007, 06:38 PM
That's metric french canadian watts based on maple syrup in your tires.

1 watt x 45 minute TT = 45 watts right?

-g
what??????????????????????????? :banana:

cadence231
11-26-2007, 07:12 PM
a penguin placed prone, pointed forward on head would rock the wind tunnel


Heck ya he would!

Ti Designs
11-26-2007, 07:53 PM
ATMO, I can say that without a doubt. The average weekend warrior has more to gain by practicing pacing, or guaging effort than anything else in a TT.

You're gonna piss off a lot of weekend warriors and helmet makers by saying things like that.

J.Greene
11-26-2007, 07:57 PM
You're gonna piss off a lot of weekend warriors and helmet makers by saying things like that.

tough love

JG

Ti Designs
11-26-2007, 08:14 PM
There's this time trial in my area on Wednesday nights, guys show up with all kinds of equipment. One day I didn't even know the event was going on, I was just out on my fixed gear and I saw someone ahead of me. I caught him and noticed that he had everything - and I mean everything. Full aero skin suit, aero helmet with the built-in goggles, tri spoke front, disk rear, big carbon aero tube bike... When I rolled up to him he instantly looked at my bike from one side to the other - I felt bad about that for a while, now it seems funny.

For what it's worth, the old BRC TT record was held by Rob Butler. He was wearing my aero helmet backwards when he set it. In the pro ranks aero stuff counts (not as much as the drugs), weekend warriors need more toys - not that there's anything wrong with that! (I did own an aero helmet at one point)

Karin Kirk
11-26-2007, 08:58 PM
ATMO, I can say that without a doubt. The average weekend warrior has more to gain by practicing pacing, or guaging effort than anything else in a TT. All of the little things are just distractions to completeing the task.

JG

Agreed. But, why not have both? Assuming we spend the right amount of time training and preparing, why not take the extra step (money permitting) and get the aero gear? It's not an either/or equation.

BTW, a friend of mine has done lots of wind tunnel testing and she told me the fastest thing she ever saw tested was a bare, bald head. Just think of how cool that would look! You could draw logos on there and everything.

BumbleBeeDave
11-26-2007, 09:09 PM
Now I have an excuse!

I always wanted to get some of these and go out riding without a helmet with them on my shaved head just to totally, completely freak people out. With the zebra outfit it would be totally perfect. I think I would have to gauge the success of the ensemble by seeing if I get arrested! :eek: ;)

BBD

J.Greene
11-26-2007, 09:21 PM
Agreed. But, why not have both? Assuming we spend the right amount of time training and preparing, why not take the extra step (money permitting) and get the aero gear? It's not an either/or equation.

BTW, a friend of mine has done lots of wind tunnel testing and she told me the fastest thing she ever saw tested was a bare, bald head. Just think of how cool that would look! You could draw logos on there and everything.

Karin,
I agree with you and I have the aero stuff. I just don't see others doing it though. I did our local tuesday night TT series this year. Very few of the cats I see at the weekend races were there. We had 5-6 tt's last year on weekends that were part of an omnium so the practice would have been helpful. I just see guys spend. Our local TT series was so good my team is picking up the event for 08.

Please ask your friend what benefit I get from shaving my head with a #1 guard. The best buz cut I've ever had came from a barber in Bigfork MT. I love your state.

JG

Karin Kirk
11-26-2007, 10:52 PM
Karin,
I agree with you and I have the aero stuff. I just don't see others doing it though. I did our local tuesday night TT series this year. Very few of the cats I see at the weekend races were there. We had 5-6 tt's last year on weekends that were part of an omnium so the practice would have been helpful. I just see guys spend. Our local TT series was so good my team is picking up the event for 08.

Please ask your friend what benefit I get from shaving my head with a #1 guard. The best buz cut I've ever had came from a barber in Bigfork MT. I love your state.

JG
The #1 buzz cut will make you look like our Senator (John Tester - his buzz cut made national news!), but it won't make you fast. It's gotta be bald, baby.

We have a Tuesday night series too. It rotates each week between RR, TT and circuit race. I live for those TTs! The very best riders have both the fitness and the gear. Sure, there are always some that feel they can buy themselves into being fast. But obviously that doesn't hold water. Similarly, if you're fit but non-aero, that won't work either.

The most important aero thing is not your wheels or helmet but your body. So really dialing your position is time well spent . I think it would be fun to have a dedicated TT bike so I could tweak it and train on it without having to swap the setup back and forth to regular road position. Next year, maybe.

ergott
11-26-2007, 11:07 PM
There's this time trial in my area on Wednesday nights, guys show up with all kinds of equipment. One day I didn't even know the event was going on, I was just out on my fixed gear and I saw someone ahead of me. I caught him and noticed that he had everything - and I mean everything. Full aero skin suit, aero helmet with the built-in goggles, tri spoke front, disk rear, big carbon aero tube bike... When I rolled up to him he instantly looked at my bike from one side to the other - I felt bad about that for a while, now it seems funny.


Yeah, I passed one of those. He really shouldn't have had a skinsuit on if you know what I mean. I was riding my Schwinn World Circuit with full fender garb and Brooks saddle.

I had the tt bike with disc and all for a while. It was nice, but it was a waste of my time. If I'm at the level where I'm considering a tt bike and the like, I want a coach along side working with me to get the stuff right. I didn't do that.

Now I love to just get on the rivet and drops and drop the pain on my buds when they are around while I still can. It's almost as fun as having it done to me by someone else that's faster than me.

stevep
11-27-2007, 06:48 AM
The most important aero thing is not your wheels or helmet but your body. .

silly woman,
you cant buy a new body.

ask roman meal.
he's trying to get his deposit back from golds gym.

Ti Designs
11-27-2007, 07:15 AM
BTW, a friend of mine has done lots of wind tunnel testing and she told me the fastest thing she ever saw tested was a bare, bald head. Just think of how cool that would look! You could draw logos on there and everything.

I read this, fell on the floor laughing, got up, read it again, fell down again. Too many things come to mind - just my bald head on a bike - no legs, no torso, no arms. Sounds like a horror flick to me! Then I got to thinking about the fastest part, they may be onto something here. Put my head at the top of a big hill and I'll be it rolls down faster than anyone else's here (rocks inside, no hair resistance...). But really, it's just another case of my getting away with the cheapest equipment out there. There are people who spend lots of money on aero helmets, I'm doing just that little bit better with my parent's hand-me-downs.

DarrenCT
11-27-2007, 07:41 AM
riding along looking at the scenary and getting fresh air > worrying about going fast

J.Greene
11-27-2007, 09:50 AM
The #1 buzz cut will make you look like our Senator (John Tester - his buzz cut made national news!), but it won't make you fast. It's gotta be bald, baby.

. I think it would be fun to have a dedicated TT bike so I could tweak it and train on it without having to swap the setup back and forth to regular road position. Next year, maybe.

I have a hard time keeping up with my legs. No way I could keep the head smooth too.

I'd like to see that TT frame. I'm sure it will be a real looker.

JG

Karin Kirk
11-27-2007, 10:26 AM
silly woman,
you cant buy a new body.

ask roman meal.
he's trying to get his deposit back from golds gym.

Yes, I think you can. I saw ads in Cosmo magazine promising a brand new body in 14 days. If it wasn't true they wouldn't be able to print it, right?

obtuse
11-27-2007, 10:46 AM
you guys can make fun of aero equipment all you want and tell stories of passing michael rich while riding a huffy but it does not change the fact that aerodynamics in a time trial style effort is the one place in cycling where an athlete can buy speed.

look at this:

uci best human effort hour record: 56.375

uci hour record: 49.70



jerk

Ti Designs
11-27-2007, 11:30 AM
you guys can make fun of aero equipment all you want and tell stories of passing michael rich while riding a huffy but it does not change the fact that aerodynamics in a time trial style effort is the one place in cycling where an athlete can buy speed.

Fast rider + aero equipment = screaming fast

Slow rider + aero equipment = screaming fool.


I can't ride fast equipment, I'm just not fast enough to hold up my end of the bargain. Deep section wheels and aero helmets tell the world that you're fast, and there's nothing subtle about it. What if I got a set of wheels that's faster than I am? They would tear up the road and I would be left sitting there...

dauwhe
11-27-2007, 11:38 AM
Fast rider + aero equipment = screaming fast

Slow rider + aero equipment = screaming fool.


I can't ride fast equipment, I'm just not fast enough to hold up my end of the bargain. Deep section wheels and aero helmets tell the world that you're fast, and there's nothing subtle about it. What if I got a set of wheels that's faster than I am? They would tear up the road and I would be left sitting there...

That's why I ride the local TT on my brevet bike, with fenders, generator hub, lights, front rack, canvas and leather bag, etc. Makes it clear that I'm going to lose 6 minutes in 9 miles!

Dave

Acotts
11-27-2007, 11:47 AM
you guys can make fun of aero equipment all you want and tell stories of passing michael rich while riding a huffy but it does not change the fact that aerodynamics in a time trial style effort is the one place in cycling where an athlete can buy speed.

look at this:

uci best human effort hour record: 56.375

uci hour record: 49.70



jerk


i dont know what this means or its significance. Please enlighten me...jerk.

Does this have something to do with swoop's testicle cream?

aLexis
11-27-2007, 11:55 AM
Best Human Effort is with all the aero doo dads, and in this case a superman position. The regular UCI record is restricted to pretty normal equipment, no aero helmet or discs, etc...