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Which cyclist hill descent position is superior? (2017)
- moneytide1 6y agoPerhaps less safe and unconventional, but the "superman" position is not listed in the article: https://m.youtube.com/watch?v=3Iz7ZMALaCY https://m.youtube.com/watch?v=3Iz7ZMALaCY
- adrianN 6y agoThat looks insanely dangerous.
- randallsquared 6y agoBut impressively more efficient!
- kaybe 6y agoIt's one of the first things you learn in trick cycling and not that bad, really. As soon as you know the failure modes of each trick and how to deal with each you're pretty safe. This one only has some that are easily caught. That speed, on the other hand... https://en.wikipedia.org/wiki/Artistic_cycling https://en.wikipedia.org/wiki/Artistic_cycling
- paulintrognon 6y agoIf it really is "not that bad", why don't other cyclists in this clip do the same?
- bob1029 6y agoEveryone has their own individual levels of risk tolerance and definition of fun.
- Steltek 6y agoIt may be banned by UCI for the excessive risk. They like to make a lot of rules, like how high your socks can be pulled up.
- kaybe 6y agoLast time I discussed this I was told that the bike in question here is fixed gear and in such a race you're not allowed to take your feet of the pedals.
- nogabebop23 6y agothis is up their with dressage, aka "horse dancing"
- privong 6y agoDon't forget "ski ballet"! https://en.m.wikipedia.org/wiki/Ski_ballet https://en.m.wikipedia.org/wiki/Ski_ballet
- kaybe 6y agoHow is there not a single image in that article..
- kenbolton 6y agoand canoe ballet: https://youtu.be/9iDVWn77VuM?t=70 https://youtu.be/9iDVWn77VuM?t=70 (unable to find a decent-quality clip of karen knight, who i have seen spin a 16' sea kayak on a dime with a canoe paddle with no above-water motion.)
- adrianN 6y agoYeah but do you do artistic cycling at 60km/h+? Even a normal fall at that speed hurts a lot without motorcycling gear.
- loeg 6y agoIt is.
- deleted 6y ago[deleted]
- thunderbong 6y agoThe comments there are really hilarious!
- deleted 6y ago[deleted]
- Scoundreller 6y agoAnd a fixie too, guess that explains why everyone else is still pedalling. You can see him use his feet to slow down the wheel before putting his feet back on the pedals.
- jerome-jh 6y agoIt is a fixie, and you'll notice he has no brakes otherwise.
- noja 6y agoThis looks painful.
- jccalhoun 6y agoI was wondering about that position. thanks
- xutopia 6y agoPretty sure he was using an electric motor to speed up.
- paganel 6y agoVery interesting, but also needed a mention of the crazy "discesista" that was Paolo Savoldelli [1], I think he won a Giro one year based on a crazy descent like that. In his case I don't think it was only a question of aerodynamics, it never is, it was also that he seemed to know best how much risks he could take when entering a curve (similar to how Formula 1 cars used to be in the past, nowadays they're too "computerized" for that to matter that much anymore). [1] https://www.youtube.com/watch?v=E4Kd8XIKoiY&feature=youtu.be&t=330 https://www.youtube.com/watch?v=E4Kd8XIKoiY&feature=youtu.be...
- biswaroop 6y agoGood point. Case in point: Cancellara's masterful descent here [1]. It's one of the least aerodynamic (I'm certain I can get more aero on a straight descent), but I would get dropped hard on the first curve. Especially on curvy descents, it's all about taking the right line at the right speed. But I am happy to see Froome's position is not even that aero. It certainly looked unstable. [1] https://www.youtube.com/watch?v=RxXqQqAc2pA https://www.youtube.com/watch?v=RxXqQqAc2pA
- ses1984 6y agoAerodynamics isn't worth worrying about until your lines are near perfect. But if your aerodynamics changes too much, then so will your lines.
- braythwayt 6y agoYou bring to mind memories of Sean “King” Kelly aggressively descending the Poggio, overcoming a 15 second deficit to win Milan Sanremo in 1992: https://www.eurosport.com/cycling/re-cycle-when-sean-kelly-s-perfect-poggio-plunge-won-his-second-milan-san-remo_sto7707054/story.shtml https://www.eurosport.com/cycling/re-cycle-when-sean-kelly-s...
- sealjam 6y agoSame race, different descent, different era, but this was also an eye popping descent Niccolo Bonifazio descending the cipressa https://youtu.be/Wb5G-18YLeI https://youtu.be/Wb5G-18YLeI
- wolfhumble 6y agoUnder heading: "Four conclusions" and as part of conlusion "1. Froome did not win because his descent position was aerodynamically superior" it says: ". . . When you have a lead when you start descending while others are still climbing at lower speed, your lead only increases until the others start descending." Your lead in meters would increase, but not necessarily in time difference?
- gherkinnn 6y agoOne thing to keep in mind is race strategy. If the opponent in front of you is out of sight, its very hard to catch up again. Even if both are otherwise identical. At least that’s what I’ve learned amateur racing in a completely different sport.
- n4r9 6y agoAgreed. Imagine two objects with the same velocity profile, but offset by a certain number of seconds. They'll take the same amount of time to reach a given displacement from when they set off.
- jerome-jh 6y agoIt is quite important to be aero when leading, or otherwise when isolated in a descent, in order to gain speed while being able to rest. Others that are riding in a group may have a sub-optimal position in a descent and pedal to compensate. They will be able to rest on the flat anyway by relaying each others at the front.
- corty 6y agoSince this is cycling, the most obvious confounder has not been controlled for: Doping.
- monsieurgaufre 6y agoDoping in descents is mostly removing fear/calmly handling high risks situations. Doping with EPO and the likes won't help.
- tokai 6y agoHow would you even dope for aerodynamic gains?
- mattkrause 6y agoNair, I guess? (Beta blockers, maybe, except that the weight gain side effects are probably worse than any gains from taking insane lines?)
- bluecalm 6y agoDon't single out cycling. Doping is rampant and risk free (when it comes to the risk of being caught) in every professional sport. They decided to do something about it in cycling while most sport federations (with maybe the exception of the UFC) prefer to turn a blind eye. There is much more incentive to dope in soccer, NFL, NBA or tennis and about zero risk of ever being caught if you're not a complete idiot about it. It's safe to say cycling is one of the cleanest sports now and wasn't the dirtiest in the past. Sure you still have compounds that are detectable for like 3-4 hours and you still have designer drugs which are not detectable yet but at least you have to deal with an organization willing to test and use biological passport while for example in soccer everyone works together so it's easy to dope and get those 100 high paced games per season done.
- ISL 6y agoDon't get scared off by the LinkedIn hosting. It appears to be a legit, interesting, and thoughtful article.
- anewdirection 6y agoNo, got scared off by the tracking. Linkedin are scum. No need to give them traffic.
- tokai 6y agoLinking the actual paper would have been better imo https://www.sciencedirect.com/science/article/pii/S0167610518305762 https://www.sciencedirect.com/science/article/pii/S016761051...
- lolc 6y agoAt the macro level this optimization to a local minimum is interesting, but on a larger view it's just sad. Using a recumbent, one doesn't need to bend into a favourable position, one already is in the optimal position. The fact that bicycle races prescribe this aerodynamically and ergonomically suboptimal frame type is damaging to the larger cycling community.
- qeng-ho 6y agoSadly, the stranglehold UCI has on organised cycling around the globe is not going to go away anytime soon, pandemic or not. The rise of "gravel" riding and races is proof that we can have more fun when the UCI isn't involved.
- lolc 6y agoI think that races on recumbents would be comparably boring. Because there are fewer tactical options when drag is reduced. So I can understand why there are races on the classical frame. But yeah, that shouldn't stop everybody else from using a modern frame.
- cultus 6y agoRoad and track races are all about closely packed pelotons going around tight turns very fast. Recumbents have very poor cornering compared to standard bicycles, and would not be safe. The performance advantage of most recumbents is often overstated as well, because the rider is in a reclining position at maybe a 30-40 degree angle. A rider on a standard racing bike can get their backs horizontal in the drops.
- kod 6y agoYou have any actual data to back up those claims? Recumbents own the unfaired bicycle speed records.
- NuclearFishin 6y agoRespectfully, I think you're both right. Certainly recumbent bikes are aerodynamically efficient, but it's worth considering that in a bike race one also needs to ride uphill, and the instability of a recumbent at slow speeds would be a disadvantage here. I haven't checked, but I suspect most hill climb records would be held by traditional bike frames.
- SeanLuke 6y agoBecause of draconian UCI rules put in place to satisfy political whims of the 1930s, we are required to consider only positions like these rather than other, much more aerodynamic ones. The danger lies in people starting to think that these are good positions. They are not: they are horrible. But professionals are forced to use them in racing.
- cultus 6y agoOn longer straight sections in descents, one can also very narrowly grip the bars near the stem. This lets you tuck your arms in front of your torso. Pedaling when you're doing ~70 kph or more can be counterproductive too. It's a lot of work for almost no speed, and it makes you less aerodynamic.
- loeg 6y agoA narrow grip results in less torque if you need to control steering. It's true that will be faster, until and unless you lose control. Then it is extremely dangerous. It also positions your hands away from the brake levers (on road bikes).
- cultus 6y ago"Mostly straight" is the operative phrase.
- wiredfool 6y agoIt’s no worse than the Froome position, which is about as bad as you can get for braking. You don’t want or need to be applying a lot of force to the handlebars at speed, so it’s not a big deal that you don’t need to have a lot of torque on the handlebars. At high speeds, you really want to be controlling the bike by shifting your weight slightly. As for the tight in position, It’s actually pretty easy to move your hands from the beside the stem position out to the brakes as long as you’re paying some attention to the road ahead.
- loeg 6y agoI agree the Froome position is awful.
- jacquesm 6y agoAnd much harder to make very precise adjustments.
- Theodores 6y agoThe article is keen to stress that going super aero on the descents for amateurs is best avoided. I second this. A lot of descending skill gets learned in teenage years. Those that grow up in hilly areas enter adulthood with innate ability that those who grow up in flat areas struggle to emulate. You can't just take chances. For absolute amateurs wanting to descend like the kings of The Tour on charity rides the trick is to have properly inflated tyres, so that means using a track pump and not some small hand pump. The track pump has a guage and the tyre has a figure to inflate to. On a charity ride with properly inflated tyres and some ability to take the correct line it is possible to cruise past people that are in a full aero tuck and pedalling furiously. The chances are that those you pass have all the gear but haven't got that tyre pressure detail right. Clearly this won't work when riding with people who are pro or have ambition to be pro. But there is great joy to be had when freewheeling down a hill on a boring flat bar old man's bike with mudguards and steel components to pass fully lycra-d riders with fully aero carbon fibre steeds.
- jessaustin 6y agoI've only ever been the most amateur of cyclists, but I find the "Pantani" position (or perhaps the nearest facsimile of it that I can perform) is the most comfortable and stable for descending steep hills at speed. With my stomach on the saddle, I never worry about pitching forward and my arms are aero yet still able to steer.
- loeg 6y agoAnd having your weight back means you can brake a little bit without going over the bars.
- kevin_thibedeau 6y agoI can do high speed descents faster on a slick tired mountain bike than on a road bike simply because the added mass bumps up the terminal velocity so it's less of a struggle. You're not proving much beating roadies with a heavier rig.
- 6y ago
- brudgers 6y agoOn it's face the hypothesis that riders are optimizing for aerodynamics on descent is suspect. The peloton breaks up because the critical limit is the performance envelop of the bike's steering geometry, braking and contact patches. It's not that aerodynamics don't matter at all, it's that good enough is good enough. The margins are elsewhere. Everyone can go fast enough to carry too much speed into a turn and have a bad day. Other positions...provide more equal distribution of body weight over both wheels This is a suspect optimization premise. Weight distributed to the rear wheel means less weight on the steering wheel and greater eccentric forces when steering...i.e. a reduced front wheel contact patch required to resist higher eccentric loads. An interesting difference between the photographs and the 3D models is pedal position. The photographs show high-low. The models use a midpoint. The high-low position puts the high foot next to the seat post where weight shift steering will create the least torque on the frame and the feet stay "under" the rider as much as possible shortening the levers creating stiffness. It looks like Froome's position maximized the amount of force he could exert to keep the handle bars steady and center of mass low -- when going downhill the further forward the rider, the lower their center of mass (all things being equal).
- gameswithgo 6y agogetting your center of mass low and forward like froome does, doesn’t result in steady handling at all, its quite bad you just deal with it. none of this weight torque stuff on the cranks has any meaningful impact when descending in mostly straight lines
- loeg 6y agoSome big races are starting to take measures to try and discourage dangerous crashes on descent stages, like not timing those parts.
- discreteevent 6y ago> Everyone can go fast enough to carry too much speed into a turn and have a bad day. But if you want to beat someone going downhill you need to get to the turn as fast as possible and then brake. On a steep enough hill aerodynamics are the only thing that determine how fast you go on the straight - you don't even pedal because your legs can't keep up.
- deleted 6y ago[deleted]
- pro_zac 6y agoThey never account for fatigue. On long descents your neck and arms will get tired. The downward back is especially stressful on your neck to hold your head so you can see forward. This means changing to a less aero position to rest your neck and arms. Some positions may be less aero but also put less strain on a rider that may be 4 hours into a race already.
- chrismckleroy 6y agoSo true. Which really makes that Pantani position solid, as you are resting chest on seat and eyes are forward.
- Ericson2314 6y agoYeah when mountain biking something extra steep, Pantani is the only way.
- jerome-jh 6y agoI suspect using triathlon bars exceeds the performance of every tested position. Unfortunately there are not allowed by the UCI for inline races. Progress is very slow in some areas ...
- mrosett 6y agoThat’s not a question of “progress” - it’s a question of safety.
- jerome-jh 6y agoWhy tri bars should be unsafe? You have control of the steering, control of the brakes and your back is flat which increases comfort. Aerodynamically speaking your cross section is quite smaller.
- fian 6y agoWhen you are on the the aero-bars your hands are not on the brakes and the your ability to perform accurate steering adjustments is greatly compromised. There is a good answer to this question here: https://bicycles.stackexchange.com/questions/10231/why-dont-tour-de-france-riders-always-ride-their-tt-bikes https://bicycles.stackexchange.com/questions/10231/why-dont-...
- jrauser 6y agoYour control is greatly reduced in aerobars, but more importantly, your ability to defend your space is hugely reduced, which makes riding in a pack extremely dangerous. This video explains why having the ability to protect your bars prevents crashes: https://www.youtube.com/watch?v=sRIsWzrMmBs https://www.youtube.com/watch?v=sRIsWzrMmBs Cycling has some dumb rules (e.g. sock length), but banning aerobars in mass start races is not among them.
- ufmace 6y agoThis. Aero bars are nice for flats and descents. I wouldn't want to have to do a tough climb without drop bars or at least flat bars. And I definitely wouldn't want to ride in a pack with drop bars with my hands not on them. That sounds like a great way to wreck.
- taeric 6y agoThe FAQ at the end is well written. Even if you are not into cycling, the entire article is very well done. Kudos to the team that made this.
- DenisM 6y agoTangentially related, I could use a better ascent position. Been popping wheelies trying to climb some of the hills here in Seattle in the lowest gear (22/34).
- joyj2nd 6y agoI am not into racing/professional cycling. But two honest questions: 1. Some positions look super forced. Do cyclists really hold their body in this position? 2. When it is going down steep my major concern is to be TOO fast, not too slow. I mean what kind of speed to they have on they way down? In fact, when I was in my mid teens, I cycled over this mountain in France. https://en.wikipedia.org/wiki/Mont_Ventoux https://en.wikipedia.org/wiki/Mont_Ventoux Once you are at the apex, it is down for like 20km. Your biggest worries will be your breaks. We were a group of youngster and some had back pedal brakes. Most of them went up in smoke. They had to use a rope to drag a small tree behind the bike as a way to slow motion in the end. No kidding.
- newsclues 6y agoDisc brakes on bikes makes stopping more effective that a stick on a rope
- joyj2nd 6y agoThis was a while ago. As far as I remember there was no bike shop on the mountain. Also doubt it would be easy to add a disk brake on a bike that has a back pedal brake.
- joyj2nd 6y agoI mean, you drag a small tree beyond you to slow your speed. If your back pedal braked has become fully dysfunctional and your consumer grade front wheel cantilever brakes is all you have left for a 20km descent, good luck!
- LargoLasskhyfv 6y agoInteresting. I feel so vindicated now :-) When bicycling downhill during good weather, on known routes and acceptable traffic I always tried to reach anywhere between 80 to 85 kph, and one time even reached 93kph! That Pantani position was something I instinctively went for. Of course that was eons ago, nowadays I'm happy to peak 65kph on flat grounds without headwind, when on a street bike. Which is rarely the case, since I'm mostly riding some vintage city/touring bike for practical reasons, which limits me to something like 45kph if I push it, and when I don't want to be sweaty it's more like 35kph.
- rurban 6y agoInterestingly nobody ever thought of Peter Sagan of a good downhill racer. The very best sprinter of course. But his position looked strange, not as strange as Froome's or Pantani's though. And I never thought he'd won any race because of his downhill advances. Only because of his sprinting abilities. Strong bias. But he always had a strong technical team behind him, and that shows.