All of the testing was done at Allied under the watchfull eyes of some of the industry big wigs when it comes to tunnel time…
Somewhat off-topic, but do you or R&A have any details concerning the new full carbon Hed disc that Bjorn’s riding?
Still in prototype phase but will be available soon- It weighs 890 grams, its very stiff and supprisingly sturdy for its weight. I believe it will be on display at the workshop on friday at R&A.
ok, at the risk of beating a dead horse (which means I’m about to beat a dead horse…), I was wondering “how likely is a 13.6 mile an hour wind at sea level?”. The answer: not very likely. Obviously, it happens, and it’s certainly worth checking the average winds for your key race sites, which is really the moral of the story in looking at the data you posted. However, after looking at some wind maps (they’re easy to find on-line thanks to the interest in wind power), even at 30 meters those winds aren’t that likely–and at .5 meters, even less so. I mostly checked out maps on the west and east coasts.
Maybe the Stinger 90 and 808 are looking a little better to me now for the age-group athlete…
As it happens my course model for IMNZ calculates average yaw.
Average wind for taupo in feb-march 05 was 9.7kph and for that period of 06 12.7kph
Using the wind direction which yields the highest average yaw on that course - WSW to SW
For a 6hr rider a 5kph wind will give around 8.1deg yaw
10kph will give ~17deg
for a 5hr rider with the wind from the same direction
5kph gives ~6.7deg
10kph ~ 13.8
If we shift that wind to SSE then it drops from 13.8 to 8.9
If we leave it at SW and put the wind up to 20kph as it was on that fateful day in 06 then the 13.8 becomes 31 and the athlete is going much slower
make of that what you will
Hey Jasonogk, what is your affiliation with HED?
Some of my athletes are sponsored by them, and they help work on equipment and positioning with my athletes like they do with Discovery, why do you ask?
Just curious. It is obvious that you work very closely with them.
As it happens my course model for IMNZ calculates average yaw.
Average wind for taupo in feb-march 05 was 9.7kph and for that period of 06 12.7kph
Using the wind direction which yields the highest average yaw on that course - WSW to SW
For a 6hr rider a 5kph wind will give around 8.1deg yaw
10kph will give ~17deg
for a 5hr rider with the wind from the same direction
5kph gives ~6.7deg
10kph ~ 13.8
If we shift that wind to SSE then it drops from 13.8 to 8.9
If we leave it at SW and put the wind up to 20kph as it was on that fateful day in 06 then the 13.8 becomes 31 and the athlete is going much slower
make of that what you will
Excuse my ignorance. How likely 20kph winds? I’m guessing quite likely. But with the higher winds come handling difficulties. Where is the trade off between deeper (90 or 808 or H3) more aero wheels vs handling benefits of a shallower wheel. I’m pretty sure I would expend a lot of energy trying to control a stinger 90. So it maybe more aero but in a real world situation it would be slower - is that right?
This, in summary, is saying to me that a rear disk and a H3/90/808 front is optimum but if it’s windy switch to a 404 or 50/60 front if it’s windy. In kona then a rear H3 is looking good with a 50/60/404 front… Is that a fair summary? 3 race wheels are optimum if no kona, 4 if likely to do kona?
ya, I am involved on several projects with them.
Is that 2.5 degree number for the 404 an outlier? It doesn’t seem to fit…
Jason,
What about the Bontrager or Rolf wheel that uses the Zipp rim but pairs the spokes? The rim shape is supposed to be the right shape if I am not mistaken but the pairing of the spokes is supposed to help it a tad. Do you have any data or information you can share about them?
Thanks,
Steve
ps congrats from this past weekend.
Hi Jason,
Thanks for the data, (this is just about the coolest thing on Slowtwitch ever). I rode a $600 Hed standard disk on the weekend and smashed my previous HIM bike split by about 30 minutes so I’m re-evaluating my wheel choices as I was very surprised at how fast the cheap disk went.
As an aside question - how do you rate the new Corima tri spoke against the Hed tri spoke?
I dont have exact #s on the corima 3 and 4 spoked wheels, but from the people that I know that know their stuff, they said that they are not all to great compared to an H3.
Tour magazine’s aero test puts it below a Campy Bora and just above a Bontrager Race X-Lite Aero Carbon
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Hey Jason,
Do the paired spoke wheels fall along the same category of not quite as fast as the HED and Zipp due to the shape of their rim?