Cd*A testing the Giro Air Attack helmet

[Abbott Smith]

Then of course there are those of us with ginormous heads (sz 8.25) who are ecstatic just to find a bike helmet, any bike helmet that fits.

My first triathlon 30 years ago, we were told we had to have a helmet, any helmet one week before the event. I rode 39 miles in 95 degree weather in a 1950's Soviet tank helmet after a one mile swim. It was all I could do to keep my face out of the front wheel (OFB). I like holes in my modern helmet better.

 

[Lief]

I rode 39 miles in 95 degree weather in a 1950's Soviet tank helmet after a one mile swim.

PLEASE tell me you have a picture of this!

 

[Lief]

I averaged about a 0.01 improvment in Cd*A. That's very good.

Jim,
For those of us that are Cd*A challenged - can I convert that .01 improvement in Cd*A into something like:

• * 5 seconds over 20KM

or

• * 5 watts at 20mph

 

[Abbott Smith]

PLEASE tell me you have a picture of this!

Unfortunately I do not. It was back in the early days of short triathlons. They were still coming to grips with idea that it didn't need to be the full Hawaiian original distances. Many of these early events were ridiculously unprepared.

This particular event got the biking segment horribly wrong. 39 miles of open farmland and no support stops. Not only did I ride with 10-15 lbs of soviet steel on my head, but I only had one water bottle for the whole ride and no food. The weather popped a blistering 95 degree false summer day in late September and there wasn't any shade.

850 started the event. I was in 30th after the mile swim. I finished 325/326 who finished. I did the 9.5 mile run as telephone pole intervals. Jog a telephone pole. Run a telephone pole. Walk a telephone pole or two or six. I was so dehydrated by that point I don't remember much after getting off the bike.

 

[Jim Parker]

Jim,
For those of us that are Cd*A challenged - can I convert that .01 improvement in Cd*A into something like:

• * 5 seconds over 20KM

or

• * 5 watts at 20mph

It's a very small change in the speed, but in a long race, it can add up.
To use Calvin's Challenge 12-hour event as an example, cutting your Cd*A down by 0.01 would allow you to go approximately 3 miles further without any extra power output.


credit to Chung's app here, for the above calculations.

 

[ratz]

850 started the event. I was in 30th after the mile swim. I finished 325/326 who finished. I did the 9.5 mile run as telephone pole intervals. Jog a telephone pole. Run a telephone pole. Walk a telephone pole or two or six. I was so dehydrated by that point I don't remember much after getting off the bike.

you should read "finding ultra" it would probably resonate with that experience; not a great read but it has it's moments.

 

[Lief]

credit to Chung's app here, for the above calculations.

Thanks Jim, I looked at his app (but distracted at the office) and couldn't figure it out quickly.
With your example I should have enough "in place data" to provide context.

Thanks.

 

[ratz]

With your example I should have enough "in place data" to provide context.

Do be aware the default is "asphalt" at ".004" that's smooth and awesome road surface; as in freshly paved or quiet suburb street. "rough tarmac" at ".008" is ok chip seal. So that number has to be set to guess at your road quality;