How to get More Aero!!! Bike Fit TT Riding Position aerodynamics explained
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- Опубліковано 11 лип 2024
- This video explains the issues of drag on a bicycle rider and how to overcome them. This video covers the basics of drag, the practical implications of it. Body geometry in relation to drag and how to reduce drag by altering your riding position. This will allow you to get faster in both conventional and TT riding positions
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There have been a few comments ref Shorter/Longer Cranks. The data from the CFD (my Commercial one, not the solidworks shown in this video) shows that if legs endure more bend at the top of the pedal stroke the drag is reduced - mainly through reduced frontal area and a lower drag coefficient. This assumes everyone's Torso angle is kept constant. To make the analysis broadly scientific, only one variable should be changed - unfortunately the saddle height and crank length are intertwined so it's impossible to change one without the other.
The difference in drag between short (170mm) and long (175mm) is not very much - 2%. Further analysis of the data (and this will vary depending on the individual) is the reduction in saddle height that is necessitated by longer cranks has more effect by lowering the rider's body into the slower moving turbulent air caused by the bike's front wheel. For clarity, the statement in the above video assumes that no other angles (ie torso) are changed. Thanks Hambini
Great vid! On a very complex subject where real life situations are very hard to model in a wind tunnel, although we can at least get some ideas.
Re. crank length, I think it depends on how your ride. If you are quite flexible and aero already, one of the limiting factors is the crank upstroke where your knee impinges on your chest. This is why pros have been finding aero gains in shorter cranks. But if you are a bit more upright (like most of us), these gains are moot.....
But shorter cranks promote higher cadence and that's a Good Thing! (But another subject entirely!)
They must be really bent over if their legs are hitting their chests. I'm guessing mortals can't do that.
Not so much hitting their chests as compressing the gap between too tight.
I imagine you're absolutely right in terms of pure aerodynamics in relation to your leg position.
There's two sides to this story though. The other side to crank length is how it affects the rest of your position, by having shorter cranks you can often achieve a more aerodynamic position because 1. logistically your legs are less in the way of your body when your leg is at the top of the pedal stroke and 2. you need less flexibility in your hamstrings when using shorter cranks to achieve the same amount of drop, because essentially your leg is moving that much less (if that makes sense?).
I believe the GB track team all went over to using shorter cranks for this reason between 2012 and 2016, even though Wiggins was using 180 cranks for the 2012 olympic TT he was on 170s or similar for the team pursuit. Presumably they did a fair bit of testing and decided the net benefit of the positional gains by using shorter cranks outweighed the "direct" aero gains from the bend in your leg when using longer cranks.
Everybody has a limit to how far their knee can go up without it hurting power output, breathing, or physically limited due to hip impingent. Shorter cranks allows a flatter torso given these real world limitations.
He looks like a Star Trek-fan.
He looks like the hapless security bloke who's always the only one killed whenever they get attacked.
In real life he would be the asset protected by the goons. :D
Totally agree
*I see what you did there*
Hambini is two pointy bits of silicone away from being a vulcan!
Beam me up Scotty
He was as logical as possible of his explanation.
@@SurpriseMeJT I think you missed the point. Check out any old Star Trek show and you will see what the comment meant.
Ha, I was thinking the same thing!
@@Methodical2 I think Jay Tee is talking about Spok.
Thanks for posting this. The visualisation of drag like this really helped me understand good positioning. Now I just have to find an aero position I can actually hold.
This is a great channel, I've got alot of videos to catch up with and of course enjoy!
thanks I enjoyed the visualization! Most of this was common knowledge to me but I think it's very helpful to understand the whys and the reasons behind things. Aerodynamics is so complicated, videos like this are so helpful.
This channel is amazing. You've won a new subscriber.
Thankyou!
Thank you so much!!... the visuals really added a new perspective to how drag works. I appreciate your efforts to make this video very much 👍
Thankyou for the feedback
loved the visual delivery of this information, very practical and helpful!
Thankyou!
This was the channel i was looking for! Finally! Good work with the modelling!
Czechnut thanks!
Just discovered your videos , really enjoying your aerodynamic focused episodes. Love the bullshit busting of some manufacturers. As a hydraulic and fluid mechanics engineer it all makes total sense! Keep it up
One more subscriber here! Thx for great, clear, accessible and useful info (great supporting visuals too).
Live long and prosper
Glad I stumbled across your channel. Great video!
My thoughts Exactly!!!
Thank you for a great video. It's good to see you share insights from wind tunnel testing, or virtual models. I would like to know more about whether a more arched back makes a difference compared to a straight TT position, taking into consideration the the relationship of head and shoulder heights.
Thanks for the feedback. It will vary on an individual basis but generally speaking the back straighter will be faster (but not by much). The reason for that is the turbulence generated on your back won't be that different between arched and straight but an arched back will inevitably cause your chest to act more like a parachute. Again I need to emphasise this is going to vary depending on the rider, where they put the bars etc. Sorry for the slightly non-committal answer.
I forgot to add the average person doesn't have the concave shaped back like the model. They tend to arch them more into a convex shape.
Well done Hambini, fascinating stuff.
Thankyou!
You describe yourself in your videos as a mere mortal but you look ripped! Good analysis BTW. I did like the CFD. I will try and get my back in line more now.
The back is key to the drag, although hard, the more horizontal it becomes the bigger the gains.
Great content!!! Thanks for the insight~
When you mention reducing drag by lowering your bars or riding on the drops, I think you should add that the point is to lower your shoulders. If your body is already leaning quite forwardm maybe horizontal, lowering the bars or riding in the drops won't help and may even increase drag. (Very bent elbows and riding on the hoods has lower drag)
Great channel Dr spock. With the current theme on GCN of recumbents how about a video on your observations subjective and objective (where possible) on recumbent highracer aerodynamics and how standard bikes compare
Hambini - great insightful vid - though I can't stop myself thinking your place is really on the Starship Enterprise as First Officer.
LOL. that tickled me.
Thank you! This will make me a better rider
More of this kind of Video please.
Hambini - [🤬🤬🤬] = 👍👍
I really appreciate learning to „think better“ listening to an engineer.
e.g. taking drag apart in [object, fluid, speed] and working through the single variables or defining the different sources of drag like [skin friction drag, pressure drag]
Thanks for the aero explanation by someone who understands it well. In then interest of looking forward to cycling for transportation (as a Climate Crisis mitigation factor), will you please consider doing a similar video where you go from casual rider position, to TT position on upright bikes, and then go to recumbents, including trikes, racing trikes, and velomobiles. I suspect these efficiency gains will become extremely valuable from an energy conservation consideration if you consider cycling and electric assisted cycling as a replacement to ICE engine powered cars and motorcycles. Thanks for the educational work you're doing.
Have you given much thought to the praying mantis position? My on the road testing found at least 3 minutes (for me) savings between flat arms and angled arms over an ironman distance. Angled arms were faster but not by much. The data was a bit noisy, so I rode multiple laps and tested several days. I used a loop ridden at various power levels and analyzed the power versus lap time data. I linearized the data. Kept power between 100 and 300 watts. Quite windy and loop was undulating slightly, so keeping even power was challenging.
I think most important potions is according to each body types for comfort, not straining, so energy can produce without any struggling, injuries, pain. With proper weight balance to each position of saddle, pedal, handle, and elbow (in case with aero bar).
Not to mention that a more aero position - leaned over further, may reduce the power from glut muscles (the largest muscle the body has). A balance between power and aero is naturally necessary.
Thanks, very interesting. Good to be reminded that it is not all about the bike....
Looking at your models in their TT position I recall some of the pros are so aero, they are looking down at the road and not forwards - not the safest position!
That's the price of speed!
For some reason I feel compelled to go watch reruns of Star Trek.... Love your videos! What have you got to say about Pinarello bikes, I'd be interested in your opinion.
As anyone mentioned star trek and how our favourite roaster looks like he's just stepped off set 🤔💭 😁👍
So, the Inverse Square Law applies to drag as well as light. Good to know.
All the drag on the legs is making me think of the new Lotus track bikes for the 2020 Olympics. They have a radical fork design with blades that are spaced out very far from the wheel itself. On it's own this fork is less aerodynamic than a conventional one but in conjunction with a rider and their legs it creates an overall more aerodynamic system.
Serious question Hambini. Firstly, I really liked the video but I have been looking at a paper called ‘Effect of Fender Coverage Angle on the Aerodynamic Drag of a Bicycle
Vishesh Kashyap et al. Is there any truth in fitting mudguards to make the air slip out the back better ? Thanks.
Your particular riding gear almost looks like Starfleet uniform (Star Trek original tv series version).
can u calculate that drag difference between those two positions in watts ?
Would it be possible to tune the air vortexes of rider, helmet, and bike to be "optimized" for 57 kph for an hour record run, that would be different than just "most aerodynamic"? Do vortexes not have waves, vibrations, harmonies?
question: all this at speed of 40kmh? 10:39 to 15:20 is there any effect say me as a regular commuter running at 15kmh is there any significant turbulence at these speeds for bikers position? and also at the same speed 15kmh is there a significant gain in watts for the teardrop design compared to the round steel frame? I am summing that aero bikes are for competition and steel rounded bike makes no difference for a commuter biker, just for the ankhs of it...
Longer crank length, by a couple of mils should be ok. One gets a reduction in required power - a couple of watts.
This is exactly why the latest and most fought over area of development at the top end of the bike industry and racing in particular is mostly focused on clothing and rider positions on the bikes and not as much on the actual bike. The national teams for the Olympics are all putting as much effort in to new types of clothing as they can. Take Vivinai at the last Olympics, apparently for the Omnium he had a different skin suit to use in every event that would take into account the different positions he'd be using and the different speeds he'd be doing while completing each event.
Can you made the same calculations for a recumbent riding position, how will this looks like?
Problem for you: flat top aero bar or round bar? Why keep the air attached if it will hit your legs straight after? Or is it best to pre-trip the flow with the round bar so your legs see decreased velocity? I've been trying to solve this for a while!
It's a very good question and some purists would argue that you should agitate the airflow so your leg could go through it without as much drag. The reality is it's based on how fast you are going and the wake it generates. The handlebars aren't really large in cross section in comparison to your leg so the effect of pre-agitating the air is not that beneficial. They are also not rotating like the wheels. You would gain a lot more by getting narrow handlebars. The aero shape is not so advantageous on handlebars, there is a difference but it's not great. Hope that helps
excellent. Top answer. Now i know my aero expert!
You said that you can be more aero in the drops, but whenever you see a tour rider off the front, a lot of times he has his hands on the hood with forearms parallel to the ground? I feel like this is a more reduced frontal area compared to being in the drops.
Sad to say this was damned interesting but my coffee is all gone and I don't remember drinking it.
Must have been within the cone, not to be confused with the Cone of Silence. Fun science!
Oh dear, time for a refill?
Bambini looking like a snack in this video
Hambini, I like your scientific appoach.
A question: Would you make this video different, after you Bike Wheels and Zipp Dimples video, with the local spiraling taken into account? Or is it still the same, because the object of the rider is bigger than the rim or the spokes?
The weighting of the rider has far more effect than the wheels or the frame. A change in rider position is changing the 80%. A change in hardware is only effecting the 20% . Hindsight is a wonderful thing but I still think the basics of this video are sound.
What a responsible, well spoken adult! That presentation was more more advanced than a PowerPoint. Crap bike tho.
Great Hambini - really like your videos! Interested in equating the cd penalty to more a tangible/ pragmatic unit - weight. If a 90kg load, bike and rider, averages 30 kph over a long distance with only moderate elevation changes, the difference between a more relaxed or endurance geometry rider position vs aggressive aero position would equate into what corresponding weight metric (e.g. Like carrying an extra 2kg load on your bike)? Some people freak out about 300g on the bike and then wax on about their latest Gran Fondo without concern to their geometry setup. Are there corresponding weight equivalent penalties of relaxed geometries at avg speeds of +20kph?
FYI - if you, TheDarkInstall, and Veloharmony joined forces, better than GCN and without lame humor. UA-cam's 3 Musketeers of Cycling!
Thanks for the feedback. I have tried to answer your question below, I apologise for the maths (I have used some SEVERE APPROXIMATIONS) but I wanted to give you a complete answer
Rough approximation for Drag = 0.5 * density * Velocity^2 * Area * Drag Coefficient
For a rider the values I would use,
Density = 1.225kg/m^3
Velocity 30km/h = 8.333 m/s
Area = 0.7m^2 this is basically a height of 1.4m x 0.5m wide for the relaxed position, and 0.6m^2 for the aggressive position
Drag Coefficient in the relaxed position 0.33, drag coefficient in a very aggressive aero position 0.2
If you do the calcs (and I don't expect you to!), you get a drag force of 9N in the relaxed position and 5N in the aero position. A difference of 4N. To get the same saving of aero drag by reducing your weight, you would need to shed about 100kg (I've used a Conti GP tyre with CRR of 0.0036). The reason why it's so big is because it's Velocity squared, so it gets big very quickly.
I repeated the analysis for you at 20km/h, you would need to shed 45kg to make up the difference between the Aero position and the endurance position.
Any engineer could pick holes in the above analysis and could point to my guesstimations which will vary from rider to rider but it highlights how much of an effect drag has and the importance of rider position.
Hope this helps, Hambini
Hence, the name Great Hambini! I thought it would be a high weight value, but not to this extent. Even if a guesstimate- directionally it follows. Always impressed by compounded or squared formula calculations when applied to everyday living. I'm so flipping my stem back towards the ground. Appreciate your time.
LOL, I actually thought you meant Great Hambini as in it was a great video!
@Hambini I was out riding with my girlfriend last week. She always sits in behind me (until we get to climbs and she wants to have a go) and on the way back we had a strong tailwind. Still sat behind me she shouted 'does this mean you are drafting me now??' as we were doing a consistent 27mph. I mustered up the most solid Joker-esque laugh I could and carried.
But, this got me wondering about the aerodynamics with a strong tailwind... if we were doing 27mph with an 18mph tailwind, is it basically like hitting the net difference of a 9mph headwind?
Also, helmets... all marketing spin/bollocks in your opinion? I have an Abus Gamechanger 'aero' helmet that, honestly, I use more for the extra heat it holds in, and a POC Octal for hotter riding. Am I right in thinking aerodynamically there would be little difference between them? Looking at the positions you outline in this video, I'm guessing only a proper TT helmet with a trail at the back of the head to cover the immediate turbulence could give any significant wattage save?
Great video btw, thanks. 👍
you can scroll down to the bottom:
www.radsport-rennrad.de/test-teile/aero-helme-windkanal-test/
the difference between the slowest and fastest helmet is 16watts at 45kph, that is indeed way more than you will find differences between wheelsets with similar deep rims.
What about the saddle does it need to be more fowards?
Crank Length - I have always been told that shorter cranks are faster because they mean less of a bend in the leg, opening up your hip angle, so you can produce more power. Some people can be down 10% in wattage due to the TT position. If people can close that 10% gap, would it be worth the extra drag? Hmm....
Vortex generators on the shoulders?
Hey i that's my first downloaded dummy solidworks model also. I named him Adam... That's going back a bit.
Another great video! However shorter cranks are more Aero as it allows for a 'better body position' i.e. lower their upper body, which far outweighs the surface area saving in the lower body.
Thanks for the feedback. On your point about the shorter cranks, if you are on longer cranks, you will be sitting lower, your head will be nearer the "spike" (because you are lower) and the frontal area of the bent leg will be reduced. The extended leg will remain the same. Essentially you sit lower on the bike with a longer crank. What is not clear is the effect that has on your power delivery, that may or may not be worse.
With shorter range of motion with shorter cranks you will feel more comfortable. Generally, you will sit higher, but you will be able to get you trunk more horizontal and you will be able to stay in that position for longer time. Thats my two cents on this... Otherwise good stuff! Keep it coming!
I think I'll have to create a video just on the discussion points of this! Thanks for your interaction. Hambini
Yes a video about this would be interesting, from track cycling the main idea is short cranks is better for power but they also claim better for aero, I just assumed this is due to the reduced range of motion allows you to drop your torso.
I've just pinned a comment to clarify the issues. Basically to conduct a fair test, I should really only change one variable. The torso angle has far more affect than the crank length for drag but assuming you keep the same torso angle, a longer crank is more aero. Nonetheless I take on board your comments
The drag force goes squared with speed, but power is cubed. So going from 30km/h to 35 the power to overcome drag is 58% higher.
On crank length, is the issue just about being as low as possible, in absolute height? In other words, you can get lower by having a longer crank, and therefore dropping the seatpost by a few cm. Or you could switch from say a cross bike with a high BB to a TT bike with a low BB, and be lower? Ultimately the limit will be whatever is safe in the corners to avoid pedal strike.
It makes me wonder now if TT bikes have slightly lower BB height from the ground?
That may be totally wrong as I suppose being lower just means you have the same frontal area but at a lower point which may not make any difference
Since my bikes have different cranks, I set the seatpost height from the pedal spindle to the saddle to get them all the same - I avoid the usual measurement from the BB to the saddle.
There are a few questions in there so I'll try and answer them in turn.
1. A longer crank length assumes you sit lower on the bike. Assuming your torso angle remains the same and you drop your handlebars an equivalent amount, you become more aerodynamic because your body sits more in the bow wave (colloquially called the spike), this reduces drag. Additionally the bent leg is further bent so it's exposing less surface area to oncoming air which further reduces drag. Nairo Quintana is a very good example of this because his handlebar drops are level with the top of his front wheel.
2. Your method of setting the height of your seat is how I would do it.
3. TT bikes as a whole have more steep seat tubes which would possibly necessitate a slight drop in the bottom bracket - I'm not sure though.
Why do you use your seat so far forward? Why don't you compensate with a shorter stem like a 90mm and a move the seatbackwards 20mm?
What are your thoughts on wider tyres for comfort vs narrow tyres for more aero! Is there more gain in bigger tyres for more comfort for less fatigue and reduced rolling resistance over increased rolling resistance, fatigue for more aero narrower tyres?
I guess ultimately this depends on the roads you are riding on and what bias you put to both. I tend to ramp up the pressure and use a fairly soft handlebar tape and my saddle flexes quite a bit to absorb vibration.
However in terms of aerodynamics, a narrow tyre / wheel
is faster.
Hambini what about tyre Hysteresis, surely that is an important factor
What about riding the drops vs riding the hoods?
@Hambini, when descending, would you be better having the cranks at 6 and 12 oclock, or 6 and 3? i.e. 1 knee bent and the other straight, or both bent?
Both bent
Has there ever been a CFD analysis of a bike rider with and without a Camelbak style hydration backpack? Vs dual water bottles?
Speaking as somebody whose knowledge of aerodynamics comes almost entirely from this video, I'd guess that water bottles are probably mostly in the spike. And you're not going to get a competitive cyclist to ride around with something on their back feeling all sweaty and horrible.
what is the CdA of each position?
At what speed does aerodynamic drag become more of a concern than friction from the bike and rolling friction? I have heard anywhere from 8-15 mph/12-24 kph.
I think around 27km-30km/h at 15 degrees, 1.01bar atmospheric pressure ie sea level.
You can tell you are an engineer.
The Star Trek edition
S bend or J bend TT bars? Is it just a case of whichever is more comfortable ?
Just seen you answered this in another video. S Bend was the answer for anyone else wondering.
You said that tight fitting clothes are more efficient, but does that mean that bare skin is more aerodynamically efficient? Just curious.
This is a bit of a tricky one. The fibres in the fabric cause drag because they are essentially a mini mountain range, skin doesn't cause as much drag because it's "less mountainous". The tight fitting clothing does smooth out contours which will help. There really isn't much in it but I would go for a skin suit as more aero, especially around the shoulder arm area.
Either will be better than loose clothing because the fluttering of loose clothing causes lots of pressure drag. The skin v aero suit is more a kin to skin friction or parasitic drag. Hope that helps hambini
As a pilot I learned of parasitic drag and induced drag. I guess that is what you mean by "skin friction" and "pressure" drag respectively. Yes?
you remind me of star trek, :)
I wonder, if when put of shape I weigh 110-115kg, but only 85 when in shape - and am particularly prone to sport love handles when out of shape, ride 30-35km/h on flats when before fatigue kicks in, how much faster would I ride once back in shape? I understand that drag is difficult to estimate, because I cannot specify the exact dimensions of every part of My body in both conditions, but very, very roughly - what would the speed gain be, in your estimate? Idem, the cardio. Under 5km/h on flats (compared to 30-35km/h) - or over that, ceteris paribus? Thank you.
So does increasing the front tire diameter from 23 to 25 to 28mm increase the spike effect to a significant degree?
Not really, the spike angle is technically a compression wave , you disturb the air immediately in front of the tyre which in turn nudges each air molecule to the side of it. The further you get from the penetration point, the smaller the perturbation. A difference of 2 or 3mm on tyre width will have an effect in the left to right orientation but the rider is fairly narrow in that plane. The rolling bit of the tyre which effects the vertical plane will be largely unaffected. I hope that made sense!
Hambini looks like a generic Star Trek Enterprise crew member in this video
No drag generated by the hands? Are you sure?
well it's all relative, and the amount generated is small compared to the body. Additionally the drag created by the hands is a precursor to the body which follows it.
I'd imagine it's been banned by the UCI but I'm surprised that no one has developed a skin suit that has a aero hump on the back like Superbike races etc. Easy to do would be better than the extention to the helmet that's usually used and can make aerodynamics worse if rider doesn't keep their heads down and flat because it sticks up in to the airflow. Also they could get rid of the bottles from the bike using the hump as a camelback water holder and filled with ise cold water on a hot day and some insulation around the outside it would help cool the riders, sure developing a way for the rider to fill it up on the go wouldn't be that hard and they could even have a bit at the bottom tip for the radios.
Drafting a truck? Yes! My kind of riding 😀👍
Hi friend Where did you study ?
RWTH Technical University
Looking swole
I don't want to sound condescending but how did nobody mention that Hambini looks like Data from Star Trek?
C'mon Hambini, if you REALLY want to reduce drag you get a recumbent bike!
In your channel introduction you typed "by may day job as an Aerospace Engineer".
fixed it, thanks for letting me know
hey appreciate the work you do here with your spare time. Cycling definitely needs some more factual media source than paid ads stuff. Perhaps you can do a video on the aerodynamics of tyre and frame clearance in the future? There are some debates going on about if huge clearance is better or next to zero clearance is better (in the aero aspect).
Thanks for the feedback. There will be a video on frame aerodynamics part 2 which will cover that. I assume you refer to the front/rear clearance as opposed to the left right clearance?
front tyre's left and right and top. I guess back isn't a problem between it is aready hidden from wind for the most part.
Damn, Spock is that you?
but if the crank is longer then one leg is more tucked in and the other more exposed
I should have been more clear in my explanation. A longer crank means you should sit lower on the bike coupled with more of a leg bend at the top of the stroke. There is less surface area exposed to the air AND at the top of the stroke you have a more favourable shape for the air to pass around. Therefore it's more aerodynamic. I could do a video just on this to explain it!
Hambini Performance Engineering I get it now. thanks!
Shorter cranks reduce hip angle, so the handle bars can be lowered. Lower handle bars reduce drag, hence the current trend in triathlon. I think you have missed this point...shorter cranks enable a more aerodynamic position, which reduces the overall by drag. Or so I am led to believe, by common wisdom.
Monsieur Hambini. I drive a car. Does my body create drag?
Depends if you are wearing women's clothes
Red is bad. Thank you.
Your hypothesis on the crank length is very interesting. James from Sigma Sport discovered some valuable insight regarding the crank length effect on cadence, as mentioned in ua-cam.com/video/L7EgeZsbIS8/v-deo.htmlm20s .
If you guys can sort of collaborate in conducting research to determine the relation of crank length with cadence, aerodynamic drag and hence resulting rider speed, BSless and technically plausible findings shall be produced.
Chapeau for your technically digestible channel :)
Thanks for the feedback. I don't know the chap so I have no idea on his background.
this guys outfit looks like he is on star trek.
My took home message is, if I really want to reduce drag, I should ride really slow...
1:13
Hot & humid air is less dense than cold & dry?!
Yes
Hydrogen atoms are very light, so H2O molecules are about half the weight of the O2 and N2 molecules which make up the majority of air.
You can see it on a psychrometric chart. If you add humidity to the air at a constant temperature the air becomes less dense.
you should open a school and teach riders how to understand every spect from the bike build and design, maintenance and this sort of stuff!
i feel like am getting a free education, but if i lived in the UK i would be pestering you for an apprenticeship!
ps... someone should name a drink or a sandwich after you. if it were a drink it would be a stiff and strong one, likely espresso ( to wake you up ) , and if a sandwich, something ridiculously hearty and nutritious, none of this white bread and baloney garbage!
i'll have a tall Hambini, extra sugar, or... i'll have a Hambini on rye bread, hold the mayo!
see? it works! in the usa apparently they do that in Deli's for movie stars... why not you? in fact your name is marvelously wizard like! i mean this all as a sincere and heartfelt compliment, despite the 12 year old boy humour!
have a great day, Hambini !
What a fantastic comment. I think I'd want it to be a metaphor for schwartzwaldmilch with nesquick. My favourite drink
Thanks for the feedback!
Jesus it's a star trek captain.
Ah, thought this had something to do with Rupaul.
seat pushed all the way forward, long stem. . . . . wot
A position further forward over the BB will open the hip angle, allowing him to sit lower and more aerodynamically.
@@sketchanderase why do I have my seat pushed all the way back on my aero setup? Dont you want your hips hinged and body locked for sprints as well? Being forward is bad...let me guess you offer $400 bike fits and have annoying facial hair
@@alexbradley9880 why do TT bikes have forward saddle positions and more upright seat angles. Because you can produce more power in a less biomechanically compromised position.
@@sketchanderase this isn't a tt bike. Stfu already you mong
hmmm shorter cranks are more aero. ask team sky
I would disagree, a longer crank means you should sit lower on the bike. Therefore the leg bend you have is increased at the top of the stroke and that is more aerodynamic. Shorter cranks themselves are more aerodynamic but if you put the rider onto shorter cranks, the rider+bike combined is less aerodynamic.
When Tour de France winning teams find a new way of working, it’s always worth paying attention.
Team Sky have for some time been testing their riders on cranks shorter than 170mm. Although it’s unclear exactly what length cranks they’re racing on, it seems the days of 172.5mm and 175mm cranks are gone.
The aerodynamic advantage of shorter cranks is widely agreed on among bike-fit professionals. Phil Cavell, whose CycleFit company performs pre-season bike fits for Trek Factory Racing, says: “With shorter cranks, the rider’s torso can be positioned lower because the shorter crank keeps the hip open. This has the knock-on effect of preventing unhelpful and inefficient pedalling adaptations due to hip impingement.”
Read more at www.cyclingweekly.com/news/product-news/are-shorter-cranks-better-188288#kmKL55P08g6ugtmp.99
I think his video assumes you keep the angle the same and simply drop the saddle height. It's not really a fair test if you also alter your torso angle as more than one variable is changing. Altering the torso angle has more effect than the changing of cranks irrespective of what cranks you are on. He clearly demonstrates that between the relaxed and the TT position.
Me: Mum, can we get a fitness coach?
Mum: We've already got one at home!
The fitness coach at home:
Use smaller wheels, lay down and be much, much faster.
You keep saying vortices slow you down. Both this video and your one on wheels. No they don’t, vortices are just effects. The Pressure differential slows you down. This pressure differential also causes vortices. But the vortices themselves don’t do anything.
After high school I studied engineering at uni. My dad was a motor mechanic and I had learnt a lot from first hand experience. You remind me of the students that had never done anything except learn from books. But didnt know one end of a spanner from another or how to change a car tyre. I like what you are trying to do but you lack experience.
I'm sorry I don't meet your expectations. Thanks Hambini
@Raymond Menz how can you possible know what his experience is from a UA-cam video. He might of been ripping things to and “fixing them” since he was 2 years old.
Shame you think that working on aircraft is inferior to motor industry ~ but a bike is a simple piece of kit compared to aircraft & motor industry and we are not here for complex theory or lecture on air drag dynamics .......
@@bengreen1262 I didnt say working in the aviation industry is inferior to the car industry. Working in my dads garage gave me experience - fixing cars, trucks, tractors and boats, spray painting, black smithing, oxy an arc welding.
To use an angle cutter in such a dangerous way shows how much real engineering knowlege he has. In fact I warned him that angle cutting discs explode without warning. So what happened. ONE DID.
In my work shop thats INSTANT DISMISSAL
In the 1st year I was at uni there were around 500 students. I was the only person able to identify what the markings on a spanner meant - basic engineering. Every electrical engineering student was unable to identify the correct way to install a car battery. ETC.
There was an extreme lack of basic
engineering knowledge with almost every student. I can only assume you are one of the idiots who pass physics and maths at high school then think you know engineering. I can only assume like them you also cannot or could not change a car tyre.
There are people like yourself who appear not to care about details. Then there are people like me who want to be told ALL the details. I dont accept anyone telling me just what to think. I want a full explanation on WHY the person thinks it.
@@petecollis4980 Only an IDIOT would use a cutting angle disc like that. A first year motor mechanic would know better.
The son of a work friend did the same thing. The cutting disc exploded at 8000rpm.
His BALLS were sitting on the GROUND HANGING FROM WHAT WAS LEFT OF HIS PENNIS.
A mix of Scotty and Spock... Scock
It's drag Jim but not as we know it.