Bicycle Wind Tunnel Test

[dangernba]

A real wind tunnel test should have a rolling ground. You can see in the video that the ground is not moving, and this affects a lot the final result.

[A2WindTunnel]

@dangernba we have our bike platform raised off the floor to get it out of the boundary layer and moving ground plane is not necessary for bicycle testing. A moving ground plane or boundary lay control system is needed with cars in proximity to the ground and most important with underbody aerodynamics seen in such cars as F1 and others with diffusers or other underbody enhancements. This is important when looking at downforce and balance front to rear. Drag is importaint in cycling not DF.

[Dryzaum]

@A2WindTunnel Very interesting and completly understandable. I just wonder if a professional guy can easily feel the drag coefficient just by practicing or that kind of test surprises him in some way. As he practice, i imagine that naturally he can put himself in a position wich causes less drag possible. Is that intuitive? Oh, sorry if my english isnt good cuse im brazilian.

[Allexxx96Reloaded]

Does the friction with the sides of the wheel spinning create any downforce?

[dedrilia]

r u confortable on the sddle?

[fabricioface]

the bike is just too big for the guy... he cannot sit on the fuckin seat

[BertPle]

To much stretch of your legs when your pedal is down.

[ashatbracks]

LMFAO at one point, looks like he ain't sitting in the saddle at all.

[Warrantti]

Your nose is not aerodynamic enough. Go to surgery !

[11pifko]

Czemu koło z przodu też się kręciło ??

[41rukahscaput]

back is to round

[wcwfan33412]

that looks like lombards singlets

[TrkMas3122]

damn! the dude is all over the place!

[bluemystic7502]

I'm pretty sure that seat is penetrating him at the end.

[Crich775]

Nice position, i prefer to stay a little more solidly on the saddle when im up riding the rivet, but to each their own.

[zach00attack]

planet x is shit

[pyraplastic]

looks uncomfortable and difficult to see the road ahead too

[calvintola]

heyheyhey....where is the smoke?

[notokid]

@profbp You push down but you also pull up, pull forwards and pull backwards. 1 revolution is composed of 4 cycles so your statement is false. You always are on your saddle and depending on the cyclist you may even be bolted to it.

Maybe you were just floating on it, in that case you were losing a lot of power...

[xxpjhxx]

@notokid ... bolted to it - wtf!!

there are so many idiot comments on this page. The rider is wearing an Australian team skin suit. I think at that level he and the people who are testing him know what the fuck they are doing!!

[lilou1003]

maybe a bit tight in the hip angle...maybe not ? otherwise good....Aggressive position better suited to short TT's

[Emovamp64]

that looks uncomfortable

[glozick]

@Emovamp64

its actually comfortable if the bike is fitted properly..

[rebelguevara1]

@Emovamp64 he isn't set right on the bike at all

[unleashedo9]

ur a fucking tard...seriously? You don't know jack shit about cycling if you think a TT rider can't see in that position...dear lord people like you piss me off

[baldbikeyboy]

No I s'pose 34 years of TTing wouldn't have taught me that much. Are you a triathlete or something useless like that ?

[baldbikeyboy]

Sorry , just checked and you're a redneck. Explains soooooo much. The position may be good on the Interstate but like most things american it won't go round corners very well. Go back to whacking your shit like LA

[mar504]

and looking at your comments... what's that make you? Your arrogance precedes you.

[plastabrick]

Being a pushbike rider at youtube level already means your on the losing end.

Nobody cares whether yourve been riding long enough to express a valid or invalid comment. Fucken amature bike riders . . . . . . . they just love talk,n about themselves either directly or indirectly . . . 34 years . . . . so what . . . . . . .

[notokid]

@baldbikeyboy Fuck You. Triathletes best athletes ever. Swim 1500m, Bike 40 km at 48 kmH then run 10 km at 21kmH. If you succeed then you can open your fuck face mouth.

[73tonyharrison73]

@notokid get angry

[baldbikeyboy]

@notokid You've got a sense of humour at least ...... triathletes can normally only stay on the bike until they get to a corner , I laughed soooooo much when they fall off on a straight road . Shouldn't they have the swim last to bathe their wounds . Ever heard the phrase "Jack of all trades master of none" ... made for triathletes.

Go back to sucking LAs cock you fag.

[baldbikeyboy]

What's the point in testing a position where the rider can't see forward ?

[1quintanaroo]

Fag........

[234TR]

wtf..wheres the white smoke??

[maeseatila]

@234TR They dont need the smoke.

[TheZipstorm]

@234TR I think they look on a computer to see the smoke

[A2WindTunnel]

@234TR: When wind tunnel testing, the rider and bike are connected to a balance (precision scale) that measures aero forces. We use the data to determine if a change was “good” or “bad”. We have a smoke wand but rarely use since we are mainly interested in the drag data from the balance. If you view our page (A2WindTunnel) we do have videos with the smoke wand.

[Sammyfest]

Looks like he's jacking his ass off.

[profbp]

Newtonian phisics works the same, only the forces matter. RPM has little to do with it. It does count, as you need a bit less force on the pedals to do the same work if you're pedalling faster. But not that less. The difference between 70 rpm and 90 rpm is less then one third in force. You must still apply great forces...

[Single0Speed]

Only under great acceration like the start of a race when you take off or go up a hill. In tt riders will get to there cursing speed of say 50kph at 90rpm and will just get in the most aero postion and be spinning the hole time, ild put money on it that over half his weight is on the saddle and handle bars the hole time he is spinning

[chutsu]

However, it is easier to maintain a high power output using a high rpm, compared to say a low rpm. A perfect example would be if you were to cycle up a hill, cycling with a high rpm up a hill is a lot quicker, and energy saving (relative to you), as supposed to a low rpm, at the same speed, over the long run.

So if you cycle with a large gear you can't handle, you are going to be slower than if you just notched the gear down to a faster rpm to maintain that same power output.

[Gibz101]

At 80+RPM you're using different muscles fibres to when you are -80RPM The muscles Fibres over 80RPM will fatigue much slower than the other fibres.

Even still. Ulrich Vs Armstrong... ?

[profbp]

And actually when you are riding really hard (just like as you shuold in a time-trial :) you don't really sit on the saddle, as you are continously pusshing down on the pedals, so you are holding yourself up. The saddle is there only to help your balance and to have a rest when you are not pedalling (eg. downhill, corners)

[AtrociousxAdam]

this is probably the most inacruate statement i've probably ever heard. nice try buddy, but you're way off.

[profbp]

That's your opinion. You have the right to have one. :) My statement is based on actual experience, what about yours?

[Single0Speed]

I would have to say to get the correct hip angle...... i bet most of his wieght is on the seat and if he is up peddling witch he will be even more weight would be on the seat, and is easyer to produce more power in that seating postion. cheers

[profbp]

Without your weigth (actually it's Earth's gravity) opposing the force you are transferring to your pedal you wouldn't be able to push down the pedal, you would be pushing yourself away. The more power you are producing (more force on the pedal) less is the weight on the saddle. (Maybe you noticed, when you are pedalling really hard, you must counter it with your arms, pulling yourself down!)

[Single0Speed]

Thats dead true...... from 0-80 rmp after you reach 80rpm your spinning and when you spinning almost all of your weight is on the seat as you are trying 2 make the peddles go round fast as can, not push down as hard as you can. and yes you can push down without earths gravity

[Single0Speed]

YEA i wana here what you have to say!! AtrociousxAdam

[AtrociousxAdam]

look at profbp's page

[1biketrickpony]

actually uci rules state that it has to be behind the bb by about 5 cm i believe thats why many people cut their saddles

[stoyki]

The UCI rules state that the tip of the saddle must not be further forward than the centre of the bottom bracket. Thats why you see soo many riders pivoting on the front of the saddle on TT bikes.

[rbonilla18]

move the saddle foward/

[awattsandre007]

its called riding on the rivet , and its fine its just his style

[JeebsFat]

This guy is way forward on the saddle!