Any chance you can give us the summary report? ;)

It's not a typical race course, so I doubt this particular course will be of benefit to anyone. It has 3ft concrete walls on over half of it.

What would you like, though? Maybe I can calculate it.

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AndyF
bike geek

Mostly curious about the yaw distribution, and how it comports with previous data.

Ok, I'll try making a histogram.

Edit: actually, the raw data can be found here --> https://docs.google.com/...91ebGF34ro1A/pubhtml

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AndyF
bike geek

:-)

Love it

I did my first Ironman there. "Esprit Triathlon" actually, back in 1995.

It's both a great location and horrific at the same time.

1995 had a headwind all the way up the main (unprotected) start finish straight. FARK. The small hill at the end of the start straight got bigger and bigger as the day wore on. By lap 41 it was Mt Everest. The back section was protected by all those trees and buildings, so there was no appreciable tailwind. The only fun was the hairpin that leads to the main straight. I entertained myself by seeing just how fast I could corner. I risked crashing, but thought that might at least give me a break from the wind for a while, so risked it. I was shattered by the end of the bike, and really really looking forward to the marathon (unwisely as it turned out).

Good parts sorta made up for it tho. The road side is arguably perfect. Two aid stations on the course so no need to carry any bottles at all. Food available at the top of the small hill. Cookies, watermelon and all sorts to choose from. Niiiiice. Porta loos or toilets at several places on the course. Getting to see your family 41 times on the bike was nice too.

Before digital cameras, I took a disposable camera with me. I got a photo of the leader on two occasions. He laughed as I sprinted to catch him to get his picture after he passed me. I took a bunch of selfies (before the term even existed) and it's funny to see the progression as I went from happy ex-swimmer to beaten man about to start a marathon. I still laugh as a I flip through those dozen or so bike selfies.

From memory there was about 87 starters and 79 finishers, and I wasn't even last, even tho IT band syndrome force me to walk the last 30km of the marathon. Losing my virginity didn't feel as good as finishing that race and sitting down on a plastic chair under a hot shower.

Great race course if you don't mind getting dizzy. :-)

Interesting Yaw angles in the video. Of course the leading rider at some spots, and the van will influence that, but still fun to see.

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TriDork

"Happiness is a myth. All you can hope for is to get laid once in a while, drunk once in a while and to eat chocolate every day"

Would be interesting to see it when actually riding "in reverse" like the Esprit Race.

Yeah, that's a bit dangerous most days. :-)

Perhaps I could interest you in multiple laps in the same direction? We could compare lap over lap. It might take 20 hrs to upload the video, but it might be fun.

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AndyF
bike geek

It took me a second to realize the speed was in km/h :p What was the wind like when you were riding? What would you guess the yaw distribution was?

I have raced it in both directions.
Although these days it's always anticlockwise.
Love the race and the City.

Really interesting. Any way to see a histogram/bell curve of the data (yaw angles)?

Unfortunately, I can't open the document due to permissions issues. I can PM you my gmail if you can't export. Thanks!

Haven't Zipp and Cervelo said (based on their previous data testing) that the typical yaw seen is in the 10-15 degrees and usually lower?

I've heard -10 to + 10

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Make Inside Out Sports your next online tri shop! http://www.insideoutsports.com/

Cool. Thanks for posting.

A plot of the ride with speed/airspeed would be nice pleas

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Developing aero, fit and other fun stuff at Red is Faster

please tell me this is part of a project where you are doing some kind of modelling so you can do testing on the F1 track :-)

Could it be the the raw data is not shared ?

Hi AndyF,

Have you attempted to use your equipment to calculate CdA as a function of yaw in real world?

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http://cds-0.blogspot.com

My apologies for the broken permissions. Here is a dropbox link: https://www.dropbox.com/...irspeed_yaw.xls?dl=0

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AndyF
bike geek

Thanks for that. 4Hz recording :)

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Developing aero, fit and other fun stuff at Red is Faster

Thanks, here is what I came up with.

Lol, you beat me to it (plus you have nicer graphics).


(Red bar is 0 to +2 degrees.)

Thanks! Where on the bike was the wind sensor positioned?

No worries, your's gets the data across too.

That is very interesting. I realize it wasn't a very long ride, however this goes against what some manufacturers are stating regarding the typical yaw seen by cyclists. That histogram makes it look like the sweet spot is definitely -10 to 10. Could even narrow that down more to -7 to 7. Goes with what Cervelo designs their bikes for. Interesting...