Aero helmet or Aero wheels.? You decide.

[ChrisH]

From http://www.bicycling.com/article/0,6610,s1-3-12-14995-1,00.html

 

 

 

Most people don't realize that a nonaero helmet creates four times the drag of a nonaero wheelset. So you can spend two thousand dollars on a wheelset, or spend two hundred on a helmet and be faster. How you put your race number on matters more than having an aero wheel; today, we glued on our numbers to get them to fit flatter. Then there's water bottle placement: On a round-tubed frame, having a bottle on your seat tube is more aerodynamic than not having one at all, and it's much more aero than putting it on the down tube. And wearing gloves in a time trial will slow you down more than using a nonaero front wheel.

[slowtwitch]

You're smoking your socks mate

[Mr Mulebar]

Biggest single improvement you can make in aerodynamics is your position on the bike.

[Brakkies Sport Fotos]

no matter what you do with your bike, helmet or waterbottle.

 

 

 

Loose weight and get faster... its cheaper as well

[slowtwitch]

 

1) Setup & geometry

2) Wheels

3)aero frame

4)helmet

bottle position

5)more aero clothing/booties

 

behind saddle is worst bottle position

best position is 1 aero bottle (Profile Design) between bars (almost like the new giant/ spesialized tt frames try to do with headtube)

 

There's conflicting data on downtube or seat tube placements, but one thing is for sure, change any one item (hand placement, bottle, etc) and it effects the whole aerodinamic profile

[Slave]

I have it on fairly decent authority that throwing your water bottle at passing taxis also makes you faster.

 

 

[ChrisH]

You're smoking your socks mate

 

 

 

Don't shoot the messenger.

[Bike Mob]

I have read the same info somewhere else... it's frightening... and nobody likes to beat the door down on conventional thought.

[Slave]

So like just how much is an aero helmet going to help?

 

This is the same as saving grams on water bottle cages. Negligable difference.

 

[slowtwitch]

You're smoking your socks mate

Don't shoot the messenger.

 

No I only shoot sheriffs 

 

But seriously, if you haven't tried it, do the test yourself, no need for articles and lab results.

 

Use a normal helmet with proper aero wheels (a rear disk even better)

and then do a test with non aero race wheels and an aero helmet

 

There's a huge difference.

 

But I agree, there is a differnce from non aero to aero helmet

[intern]

 

[intern]

There. Check how fast that aero helmet makes me.

[buckstopper]

From http://www.bicycling.com/article/0' date='6610,s1-3-12-14995-1,00.html

Most people don't realize that a nonaero helmet creates four times the drag of a nonaero wheelset. So you can spend two thousand dollars on a wheelset, or spend two hundred on a helmet and be faster. How you put your race number on matters more than having an aero wheel; today, we glued on our numbers to get them to fit flatter. Then there's water bottle placement: On a round-tubed frame, having a bottle on your seat tube is more aerodynamic than not having one at all, and it's much more aero than putting it on the down tube. And wearing gloves in a time trial will slow you down more than using a nonaero front wheel. [/quote']

 

They didn't define what is a non aero helmet - does it have a peak for example. Its also relevant to measure the difference in terms of saving at what wattage and over which distance. What effect would wearing a black tt helmet on a hot day vs a modern racing well aired helmet have on power loss through heat vs the aero advantage.

[slowtwitch]

well done intern

[ChrisH]

You're smoking your socks mate

Don't shoot the messenger.

 

?

 

No I only shoot sheriffs?

 

?

 

But seriously' date=' if you haven't tried it, do the test yourself, no need for articles and lab results.

 

?

 

Use a normal helmet with proper aero wheels (a rear disk even better)

 

and then do a test with non aero race wheels and an aero helmet

 

?

 

There's a huge difference.

 

?

 

But I agree, there is a differnce from non aero to aero helmet

[/quote']

 

 

 

*Looks in garage for deep section wheels, rear disk wheel and aero helmet but doesn't find either*

 

Unable to do the test myself due to lack of test equipment I then did what any self respecting scientist would do. I used Google.

[Kiwi]

 

 

 

Interesting articles and data  for comparison purposes:

 

http://www.bikeradar.com/news/article/how-aero-is-aero-19273

 

http://www.specialized.com/OA_MEDIA/pdf/road%20vs%20TT%20research%20FINAL.pdf

 

http://www.bikeradar.com/news/article/technique-can-aero-bar-performance-17815

 

"Conclusion:

Aerodynamics plays a huge role in cycling efficiency. Our time trial (aero) configuration showed an aerodynamic savings of 33% over the road configuration, meaning that roughly 70% of the test rider?s power on the track went into overcoming aerodynamic resistance?a number generally agreed upon by bicycle scientists.

Based on wind tunnel data and estimated rolling resistance coefficients, Excel simulations of the track tests predicted total power savings of 25%, compared with 24.1% and 21.7% from the actual track tests. These numbers tell us that wind tunnel and real world testing can yield fairly comparable results, but there are still undeniable challenges with real world testing, including environmental variables.

Though our tests obviously determined that time trial positions are much more aerodynamic than road positions, future tests will focus on yielding more precise measurements by looking deeper into the individual effects of position changes and equipment changes, including helmets, frames, wheels, etc."

 

 

 

Kiwi2009-07-02 07:16:20