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View Full Version : Trek DH Racing's Wind Tunnel Testing




FullMonty
08-28-2009, 05:15 PM
http://dirtmag.co.uk/news/category/dirt-team/dirt-exclusive-trek-wind-tunnel-testing-in-san-diego/dirt-1235605.html

think this will ever be a significant factor on the world cup? seems to me that the frontal area offered by the bike pales in comparison to that of the rider, and with weasel-squeezers out of the equation, changes are pretty limited I would think.




biggles604
08-28-2009, 05:35 PM
I wonder how much drag a TLD pyjama suit has.

Feral
08-28-2009, 05:46 PM
The concept of getting immediate feedback to how effective different body positions on the bike are for aerodynamics sounds like it has promise, that's probably a simple and cheap way to gain a few tenths or hundreths of a second.

builttoride
08-28-2009, 05:47 PM
Haha, thats just ridiculous. Average speed for a DH race is probably something like 30-40mph? air resistance is hardly even a factor compared to line choice. why not just pump your tires up for less rolling resistance, it will be a lot more significant than drag at those speeds. Oh well, I guess it was just for a laugh, and not really serious, so fair enough.

Ando
08-28-2009, 06:10 PM
Haha, thats just ridiculous. Average speed for a DH race is probably something like 30-40mph? air resistance is hardly even a factor compared to line choice. why not just pump your tires up for less rolling resistance, it will be a lot more significant than drag at those speeds. Oh well, I guess it was just for a laugh, and not really serious, so fair enough.

ok I will bite....I am sure whiny Wayne P can drag up the study but they looked at speed and air resistance in BMX and MTB....I recall anything over 20 had huge gains with aerodynamics. I totally agree that skill and line choice is huge in dh...but equal riders on equal lines will go faster if tucked bettered longer. Now the bike shape may not be as big a factor as the body shape! (think blood diamond-coleman) ha

On any course that has high speed....tuck is key...look at sunpeaks in the open area by the cattle guard, many people just sat there no tuck. Take a speed gun and it will be very obvious which shape can go fauster.

And as for tire pressure the opposite of what you say can often be true. If you race on concrete sure the hard tire rolls pretty faust on smooth ground. Now when you are DH'ing the ground is often not smooth and a lower psi such as 22-25 will roll better than say 40 as the tire stays on the ground contour and is not fighting to reform and negating the work your suspension is doing...

Hell and one more...soft active suspension will roll smoother and fauster through rough terrain than a very stiff set-up...you stay more stable going in a forward direction instead of bouncing up and down all over shop...robbing you of forward speed.

And yes Biggles PJ's are sure aero...my daddy tells me that at bedtime every night...

Oldfart
08-28-2009, 06:11 PM
Haha, thats just ridiculous. Average speed for a DH race is probably something like 30-40mph? air resistance is hardly even a factor compared to line choice. why not just pump your tires up for less rolling resistance, it will be a lot more significant than drag at those speeds. Oh well, I guess it was just for a laugh, and not really serious, so fair enough.

I agree air resistance of the bike in comparison to all the other stuff is pretty small. Air resistance of the rider is far greater. If the rider really wants to be aero, loose the visor, loose the baggy clothes. But of course image is more important in DH than actually going fast.

And before someone gets their TLD jammies wadded up up their pink starfish, that was a joke. Except for the visor thing. Visors don't really do much now do they.

jefg
08-28-2009, 07:56 PM
http://dirtmag.co.uk/images/uploads/news/trekwind_293.jpg

so, let's see somebody hit a rock garden or drop in this "aero" position. please take a video, I'd love to watch :lol:

Bushman
08-28-2009, 08:42 PM
yup...the tuck is good for long smooth sections.....like the road

Tdiddy
08-28-2009, 10:38 PM
I remember a study a while ago where 85% of your energy goes towards fighting air drag at speeds of 30km/hr. I would say that's very significant. Nico used to test whether it was faster to sprint long smooth sections or tuck, and time the difference, with the tuck often being faster with more energy conservation than balls out pedalling. On a track where Rachel Atherton protested others wearing tight jerseys by writing skinsuits suck on her arms, I think results at Canberra definately can be affected by more efficient riding positions on such a smooth open course. Look at Ft. Bill last year, where Ben Cathro had his best result, top ten, wearing a giant black condom. It definately plays a role.

Bushman
08-28-2009, 10:42 PM
all very true.......

now hold that tuck on any MBT trail and see how long you can stay on your bike.

kperras
08-28-2009, 10:57 PM
Look at Ft. Bill last year, where Ben Cathro had his best result, top ten, wearing a giant black condom.

:lol:

Tdiddy
08-28-2009, 11:30 PM
all very true.......

now hold that tuck on any MBT trail and see how long you can stay on your bike.

certain tracks, like ft. bill and sea otter down under, have long open sections that aren't technical that would allow for some more aerodynmic riding positions without the worry of getting bucked off your bike. There's a reason teams have been testing other frames with less travel for world champs this year. Look for specialized running the sx trail bikes instead of the demos for instance.

Ando
08-28-2009, 11:51 PM
certain tracks, like ft. bill and sea otter down under, have long open sections that aren't technical that would allow for some more aerodynmic riding positions without the worry of getting bucked off your bike. There's a reason teams have been testing other frames with less travel for world champs this year. Look for specialized running the sx trail bikes instead of the demos for instance.


thats just crazy...are they trying to win races with tactics? say it aint so! its only the worlds...I am still surprised that DH skiing and DH mtb do not share more than they do...as far as aero. And no not tucking through rock gardens, ha. but when it is super open and fast...makes allot of sense...as does a different bike for different courses....braap

Bushman
08-28-2009, 11:55 PM
you can pick up another Kph by putting one hand behind your back

Tdiddy
08-29-2009, 12:24 AM
volvo cannondale have been testing a new dh bike for worlds:

http://www.seriouswheels.com/pics-stuv/Volvo-Extreme-Gravity-Car-Woman-Top-1024x768.jpg

aShogunNamedMarcus
08-29-2009, 01:28 AM
tell me thats a girls ass I'm pervin on

:P

GladePlayboy
08-29-2009, 03:58 AM
God I hope so, for both our sakes...

Rainmaker
08-29-2009, 04:22 AM
Ahhhh
The things companies do when they have more money than brains. I love bike companies (and ski companies for that mattter).

CRFRDH
08-29-2009, 04:35 AM
God I hope so, for both our sakes...

:smokey: jajajajajaja....please.....jajajaja....looks like a giant banana suit...

Bushman
08-29-2009, 09:08 AM
nice boots

Chainstay
08-29-2009, 09:14 PM
Seems interesting that tucking could beat balls out pedaling....

Tdiddy
08-31-2009, 01:34 AM
it's all strategy, if you save energy by tucking instead of sprinting, you might be 1 second slower in that section, but 3 seconds faster for the rest of the course because you're not exhausted.

craw
08-31-2009, 05:21 AM
nice boots

I was going to mention those heels... Surely something more swoopy would be more, er, aerodynamic?