The fastest I've ever gone on a pushbike was around 80 km/h (50 mph), down a hill.
It's pretty fun and a great adrenaline rush, but holy shit it's dangerous. It's not like I was wearing protective gear, my polystyrene helmet and lycra wasn't going to protect me at that speed. All it would've taken for me to fuck myself up was a large stone or a nail in my tyre or even just speed wobbles.
I stopped hill bombing pretty quick. It's not really worth the risk.
The fastest I've managed on a flat is around 60-70 km/h, drafting behind a random car. That's also not safe, if the driver tapped their brakes, I'd go straight into them.
There's something so cool about going at car speeds, but without a motor.
As I get older, every time I find myself cruising at 50mph in traffic on the freeway on my motorcycle, I ask myself how the fuck younger me thought this was an acceptable speed at which to start lanesplitting. Was I insane? Nowadays I'll start around 40, more like 30, and never more than 10 over.
It's a shame so many motorcyclists die young, before they get a chance to "grow into" some safety sense. I distinctly remember talking with my friends age 12 about how (apologies) "gay" helmets were on our bicycles. We'd speedbomb hills too, it was fun. I remember feeling no fear back then. I remember my parents telling me "you're an idiot for thinking you're invulnerable."
Why do we think that way when we're young, that we're immune to damage? What changes? We experience more death firsthand? If I hadn't had to clean up car accidents and watch a friend lose her intelligence to a helmetless bicycle accident, would I still feel invulnerable?
I wonder about this woman - did she do this because she lacked the fear? Or did she feel it, and all the positives of doing it overruled her fear? Maybe she was just confident enough in her safety measures to do it anyway?
I was maybe 10 or younger and I was speedbombing downhill with my younger sister. We were fearless and very, very fast. Of course we weren't wearing any helmet or whatever. One time as we were racing, she was winning, she shifted her bike toward my direction and slowed down. I ran into her bike and flew out of my bike. Next thing I know I'm in the air, falling down towards the hill. When I finally hit the ground, I uncontrollably rolled downhill another maybe 10 meters. All my face and body was covered in blood and soil. My mom, seeing this incident from far away, ran for help. She told me, when I grew up, that when she was close enough to see me she was sure I was dead because of all the blood on the asphalt and what not. But thanks to the gods of probability, I didn't even break a bone. I don't understand how can human body can be so resilient that a 10 year old kid can survive such an accident without any damage other than his skin (and it wasn't permenant, I forgot about this event until now). I was stupid and I probably did that again and again, possibly even the next day. Now 15 years later, I bike everyday, but I bike very cautiously. I was lucky once, I don't wanna try my luck again.
Cyclists tend to break bones at slower speeds. Pro-cyclists racing down mountains will lose a lot of skin in a fall but unless they hit something hard (rock, pole, wall) they don't tend to break bones. At walking speeds, a sideways fall often results in broken collar bones and wrists.
It is all about the angular momentum of the cyclist wrt to the road.
Whenever I go on a group ride with someone that doesn't even have gloves on, I say I'll give them five bucks for every second they're able to lightly press their knuckles to the concrete, then rub them back and forth vigorously.
Nobody's ever managed to make it more that a second.
I was 9 when I fell off my bike and broke my femur. Being in traction for 4 weeks followed by a full body cast for 12 was not a very fun way to spend the 4th grade.
> At walking speeds, a sideways fall often results in broken collar bones
That's pretty much what happened to me. I was going walking speed on a bike, popped a wheelie, handle bars came off, I tumbled forward and landed collar bone first onto a curb. Hairline fracture at about age 14.
I pulled the brake lever on my road bike once, and it FELL OFF. Went right into the front spokes and launched me over the handlebars like a cannonball. It was like putting a metal rod right into the front spokes.
Square-cube law; someone twice the size has eight times the mass and eight times the force, with only four times cross-sectional area to support it. A ten-year-old's bones and other tissues suffer half[1] the force per unit area in a crash, so require only half the material strength to avoid whatever level of damage.
force is proportional to the cross section of the muscle.
This never made any sense to me. Muscles are made up of groups of fibers, which are made up of chains of sarcomeres. How could strength be proportional to cross sectional area rather than volume of the muscle?
> How could strength be proportional to cross sectional area rather than volume of the muscle?
The same reason that's true of strength of passive members; the limiting factor is the force that will cause shearing, which is basically the strength of one bond in the lengthwise direction times the number of them supporting in parallel in the cross section. So, given the same material, cross sectional area determines strength.
> But, by my understanding, the sarcomeres, which are the source of the actual movement, don't run end to end, they're chains.
It doesn't really matter, except the not being homogenous end-to-end means it's the weakest point that matters. But, irrespective of the structural details, there is some force in the direction of contraction that will cause failure, and that force is proportional to, basically, the number of linkages it is distributed across in parallel (not connections in series, such as along the chain) which is proportional to cross-sectional area.
> The entire line of reasoning seems to rest on the idea that the smallest unit we consider runs from one end all the way to the other.
It is not (in fact, the entire reason it is true of any material is because even structures which seem to be end to end are composed of smaller structures with fallible linkages; if there were indivisible end-to-end structures, this would cease to be a concern.)
To clairify, I was talking about the force exerted by a asphalt plane slamming into you at X m/s, not the force exerted by your muscles.
Although I was basing that on force exerted by gravity (which is proportional to mass), whereas deceleration might be spread out proportional to length, so it might work out to L² anyway. It's too late to edit though.
That is indeed a big factor, but another important factor is that the bones of children are less brittle than adults. I retired from being an EMT last year and it's amazing what kids literally bounce back from while adults break a hip from just falling in the yard.
I believe that's true, but I doubt it's really a factor in this phenomenon of kids surviving high speed crashes that would likely be fatal to adults. It's really just a matter of a less massive body generating (exponentially) less force on impact.
I didn’t know there was a name for this. Speedbombing...Like another commenter, aged 10 I took on the biggest hill in the area. 30 years later, I still bare the scars and memories of the pain at being cleaned up by a very unsympathetic nurse at the hospital. Which was more painful than the crash, as I remember it.
I have come to realise that there's quite a survivor bias in childhood experience, too, whenever someone suggest that today's kids are pampered and parents are hysterical and after all, when we were kids we did all these fun things you cannot do anymore because safety - but yet we survived just fine, didn't we?
I looked up the stats going back a few decades - in the sixties, an average hundred kids died in traffic each year here in Norway. Now? Two or three. Yet we drive more and the population is significantly larger, too.
Drowning (the other biggie) is down by a similar factor.
Generic accidents? Also down by at least an order of magnitude.
We may sigh all we want that kids today are glued to their playstations while we were out building tree huts, conducting -ahem- applied pyrotechnics experiments and similar - but the fact of the matter is that kids today survive childhood. We didn't. :/
The main difference is being supervised by a reasonable adult or not and how streets near homes have changed.
Kids can only be left to free roam in a very safe environment - and even that is not entirely without risks. Alternatively only kids who are shown to be reasonable can do that - it takes parental sensitivity.
I remember doing stuff like this as well when I was younger. I think it should be a collective responsibility of parents to instill in their children that safety is important. I don't let my children ride their bikes without helmets and that's the norm where I live, not the exception, and I think a great deal of it has to do with the fact that the parents around here are very involved in their children.
When you're young and lucky you lack both the experience of bad things happening to you and others and, if you're healthy, you think 'well I've always felt pretty much the way I feel now and when I get hurt I heal pretty fast' so you don't think too much about it. Also, most of the people around you tend to be in the same state, though there were probably at least a few exceptions but they were so few that they're easy to overlook.
Then you get older and experience aches and pains where there were none before, when you get hurt instead of shaking it off you either take longer to heal and/or need a trip to the doctor, maybe you deal with a nasty illness/injury or two, see people you know dealing with and/or taken out by nastier things. Throughout all this you start becoming your parents saying things like 'stop running around with that... you could put an eye out' (hell, by this time you probably met someone who did just that)
I figure in a few more years I'll be driving 20mph in the fast lane with my blinkers on... after all, what's the rush? Hey kids, get off my lawn! ;-)
> Why do we think that way when we're young, that we're immune to damage? What changes?
I'm not saying that all of the "life experiences" answers are wrong, but I think there's more to it. For an organism to be successful it has to survive (to a point), but it also has to be efficient at doing physical tasks. I think we're naturally inclined to push our limits at a young age so that we know where those limits are, and we can more safely straddle them when we're older. Evolution could have made children cautious, and it did, to an extent. But there is a balance. A child who is too cautious never learns how to run safely, and an adult who doesn't know how to run safely can't chase a gazelle very well.
"Why do we think that way when we're young, that we're immune to damage? What changes?"
I see you've received a lot of answers already, but not an explanation (worthy by my standards). Here's my stab on it:
1. Remember how everyone got to ride a bike in the first place. It looked dangerous, yet we had to get over our fear AND try to suppress it consistently long after the point of riding and not falling any more. And that kind of fear suppression exercise was necessary again and again all over our childhood. It's no wonder that with so much repetition it grew to become part of our character, at least for a while, at least until the voices that once encouraged us to overcome our fears went silent.
2. The level of responsibility we bear and the awareness of it, including the responsibility for ourselves, especially enough to feel it in our choices, grows only with time. As younglings, we care less about "serious and boring" (i.e. "act responsible") and more about "fun and exciting" and weight our decisions accordingly.
My current theory on "why do we think that way when we're young" is a disconnection in logic between the older perspective and younger perspective. You don't think you're invulnerable when you're young you simply just don't think about what happens next. When your brain matures and you get older you realize you're going to be around a much longer time than you ever imagined. Your pre-frontal cortex gets a stronger voice and says "watch out you'll die in a second doing that!"
An adults perspective is they young think they will never get hurt. A youths perspective never thinks about getting hurt in the first place.
>Why do we think that way when we're young, that we're immune to damage?
Probably overprotection by parents. When I was a kid I was left alone with my friends with no parents supervision a lot.
We did very risky things and risked our lives several times, but in controlled and normal environments like climbing trees and going to the mountain. When something went wrong you will get painful feedback like bruises. But you knew what your limits were.
Quite interesting, those children that had their parents forbidding them to go with us actually had traumatic experiences later in life, once they were free from their parents. They will buy a motorcycle or car, take risks and die or almost die.
It was like they lacked the experience we had and replicated it, but with machines in non humane environments. Instead of bruises they will crash a very expensive car.
I took risks as a kid and then went out and crashed cars and motorcycles as an adult. I didn't learn anything about motorcycle dynamics from falling out of trees or face-planting off shoddy bicycle ramps.
In my case it's not that I've gained fear, it's that self-preservation is now worth more, mostly because I've spent so much time filling this brain with things. I'm legitimately worth more now than I was in my daredevil days, so I expend more effort protecting myself.
Well, one could easily make the opposite argument: the life of a young person is worth more because more life is left. Presumably that's why we find it more tragic when a young person dies than an old person.
At least kids seem to be getting better about helmets. It’s really really rare that I ever see a kid not wearing one when mountain biking, at least where I am.
Helmets have become more common for a lot of activities. They used to be unheard of in skiing unless you were a racer and now are probably worn by most--especially kids.
Of course, e-scooters and bike shares provide a counter-trend as they don't make it convenient to have a helmet.
> They used to be unheard of in skiing unless you were a racer and now are probably worn by most--especially kids.
Yea this one surprised me recently. I learned to downhill ski as a kid in the 80s, and never once saw anyone with a helmet. I obviously gave it up when I moved to Florida, but now, decades later I’m living somewhere I can go skiing again and was shocked to see so many people (even adults!) wearing them. The group from work I was with was equally shocked that I wasn’t wearing one. They were also shocked that I was wearing jeans and not one of those hundreds-of-dollars skiing outfits, but whatever. I mean I guess helmets make sense but it just feels unnatural, as unnatural as bicycle helmets (which we also did not wear back in the 80s) feel to me. I’ll never get used to wearing one of them either.
> They used to be unheard of in skiing unless you were a racer and now are probably worn by most--especially kids.
What, seriously?
What kind of skiing are you talking about? I've never once seen anyone wear a helmet for cross-country skiing, and I wouldn't think it's necessary anyway. For one thing it's usually walking pace, but also snow is soft.
Presumably grandparent means downhill. Twenty years ago, you basically couldn't buy an adult-sized helmet for alpine skiing even if you wanted to. These days, it's weird not to have one.
I think the change was due to some high profile deaths from tree collisions in the late 90s.
As I recall, racers have worn helmets for decades but it was pretty rare for recreational skiers until 15-20 years ago. I think another factor is that helmets for a lot of kids' activities have become more or less expected, especially among demographics who do downhill skiing as a family. And, if you're telling your kid they have to wear a helmet, a lot of parents probably feel they sort of have to as well.
ADDED: I also wonder if the rise of snowboarding played a role because backward falls where it's easy to hit your head on ice is probably more common than with skis.
I don't downhill ski much these days but I did ski at Squaw Valley a couple times recently because of an event there. And I was definitely an outlier in not wearing a helmet. (In my partial defense, I do wear a hat with impact resistant material sewn in (D3O) and I'm not exactly banging down moguls through the trees these days.)
In the longboarding community, it's considered extremely bad taste to film without a helmet un, precisely because kids are impressionable. I've seen people shouted out of meets.
I have never seen someone at the mountain bike park without a helmet. That would be just insane. Also most of the people taking on the tough trails have full face helemets.
> Why do we think that way when we're young, that we're immune to damage? What changes? We experience more death firsthand? If I hadn't had to clean up car accidents and watch a friend lose her intelligence to a helmetless bicycle accident, would I still feel invulnerable?
There's a theory that, from an evolutionary standpoint, young men are wired to fearlessly fight and die to protect the rest of the community. If they survive long enough, they calm down and take on other roles, letting the new generation of kids take over as cannon fodder.
Take with a grain of salt, obviously, because we're all a lot more complex than our evolutionary history, but it seems plausible.
There's definitely a fearless aspect that comes with youth. I recall mine vividly and there were certainly times I gambled with my life. It's helped me grow as a person but I could never recommend such recklessness in hindsight. Perhaps some things can be learned but not taught.
I have been experiencing the same. A few factors I can think of.
Exposure -- As kids, we aren't exposed to consequences of accidents, blood, etc. So because we have 'seen' less of it, we believe it cannot happen to us.
Responsibilities -- I believe the 'responsibility' factor kicks in as we age. When we are kids, we are for ourselves so we end up taking more risks. As we get older, get married, have kids, watch our parents getting older, we start caring more for security as life seems to be important because of our dependents.
We are adults for majority part of our lifetime so as we grow older we only become habituated to remain careful about our life.
> Why do we think that way when we're young, that we're immune to damage? What changes?
We've evolved this way — not just humans, but mammals in general, and probably other species too. Risk-taking when young is adaptive for the community, if not always for the individual. If no one ever hunts in the place where a tiger was once seen, how will the tribe ever find out that the tiger has moved on?
An EMT in the family told me they call the ones without helmets "future, organ donors." Said they see too many of them that don't make it. I just try to stay away from anyone on a bike when I'm driving. I don't do it myself, though, cuz I was worried about potholes, deer, and so on. I figured I'd crash over something small I didn't see or avoid in time. My reflexes aren't that good. ;)
I think people are overestimating the merit of normal bicycle helmets. I think the actual effect is something like this ([1]):
> The most reliable estimates indicate that at speeds of up to 20 km/h helmets reduce the risk of head injury by 42%, the risk of brain injury by 53%, and the risk of facial injury by 17%, whereas they increase the risk of neck injury by 32%. These estimates are partly based
on research carried out in countries like the United States and Australia, where standards for bicycle helmets are stricter than they are in Europe and can offer protection at higher impact speeds.
In wikipedia [2] I find this quote: "This effect is statistically significant in older studies. New studies, summarised by a random-effects model of analysis, indicate only a statistically non-significant protective effect"
And to the parents around here, make sure your kids know when to not wear a helmet (choking accidents [3])
Bicycle helmet safety is one of those things that will never be accurately covered by statistics, because most cases where the helmet did its job don't end up in the stats as there are no significant injuries.
In the only serious bike accident I have been involved in, the victim would have walked home on their own feet had they worn a helmet. Instead, a fall from the bike on low speed and hitting their head on tarmac ended up in serious head injury and 6 months in the hospital.
Had they walked home, it would have not ended in the stats.
+1 I once landed head first on a mountain bike going downhill. The helmet literally exploded in a million pieces. Walked away home unharmed. Didn't go in the stats.
It was my third time snowboarding and the snow was compact and icy. I was going relatively fast for my control. Caught an edge and fell on my back with my head doing a whiplash. I was probably unconscious for 10 seconds or so. Lay there for another half a minute to gather myself and stood up. Checked the helmet, there was a massive crack. Checked head for bleeding. No bleeding! I walked away and went to the car to get some rest.
I wonder if the neck injury thing is just because a "lesser than" injury is actually getting reported? I haven't seen anything in the article about it, but for example iirc there was this hullabaloo about motorcycle helmet data indicating an increase in back injuries for helmet-wearers, until someone pointed out that dead-on-site riders would be reported as simply "dead," with their injuries unaccounted for.
The helmet sticks out a couple of centimeters and can increase torque if you don't fall straight down. It's plausible that it can cause more serious neck injuries.
A flat shell on front and back would not absorb a hit well if at all - and those are relatively common accidents.
Typical fall has the first contact either direct front or direct back based on kinematics which means they're subject to most force. Falling on side of head is somewhat more rare. Falling on top of the head is rare.
> only a statistically non-significant protective effect
I don't think this phrasing makes sense. A particular study may find a positive effect but with p>0.05, but that depends as much on the size of the study as on the effect itself.
Not sure why you were down voted. The risk taking mechanisms in our brains aren’t fully developed until around that age. I thought this was reasonably well understood
50mph downhill is very dangerous... indeed. When I was 12, I rode downhill with a friend riding in the back... really fast. But I doubt it was more than 25-30mph. I hit a dip, somehow managed to do a front-flip, landed on parked car and asphalt. I scraped my knee so deep, it didn't bleed. It was white! Instead of going to doctor, I unrolled the skin back onto my kneecap, went home, wrapped it up, and went to bed, and hope for the best. Almost 30 years later, I still have a nasty scar from it. Since the incident, I developed deep fear of going downhill and losing balance. Ski? nope. Snowboard? ugh. I can ride them, but if I find myself going just a wee bit fast, I brake.
Long winded way of saying... yes, riding bicycle even at 30-40mph is no joke...
One thing I love biking (I bike everyday as I commute with a bike and also usually bike randomly in the street for fun) is biking is fun both slow and fast. There is something very appealing about biking as fast as car, almost like showing off your muscles to the driver. Biking slow is also fun since it requires a lot of balance. Sometimes I try to bike as slow as pedestrians. At that speed you really need to balance yourself as even the slightest perturbation can cause you to speed up in order to rebalance. It's very calming, refreshing and relaxing once you figure out how to bike that slow.
I was on a mountain ride here in Colorado a few years back when I got a little too exuberant -- I was going about 45 mph when I hit a corner that was sharper than I thought, and the tires slid out from under me. I tumbled for quite a way, and when I stopped I was missing a lot of skin and my shoulder was dislocated (tore through my labrum in the front). Fortunately a nice woman stopped and took me to the emergency room (her three year old daughter told me "I only ride my bike on flat ground" which I deserved). I got off lucky, only 3 months of physical therapy. I'm more careful these days.
I once did "over 50mph" free-wheeling down Parley's Canyon on I80, from Park City to Salt Lake City (~2000' drop in 10 miles; 700m fall in 15km). There's no alternate route there, so bikes are allowed on the Interstate. I only slowed down after I had to swerve out into the traffic lanes to avoid a broken wooden pallet lying in the shoulder. It's not the steepest of the local canyons, but one of the fastest for bikes because it's straight, wide and has good visibility of the road ahead.
I don’t know, I don’t think there is anything more dangerous in riding a bike at 80km/h than it is eg to ride a car at 200. Both can be fine if the situation (traffic, view, ground, etc) permits it. If the situation isn’t safe then both are stupid things to do.
That said the thing from the linked article is obviously on the more dangerous side, since the lane is super narrow and the margin for errors low.
I have a 53x12 setup and top out at just above 120 cadence. It really is interesting to be going 70kph, passing mopeds!
When I'm drafting behind these random cars, vans, and box trucks, I stay right at the edge of being in the slip stream. If the vehicle ahead does something dodgy, I have an escape route or at least a bit more distance to brake.
Getting dropped out of the slipstream is really a drag! Easily lose 20kph+ of speed.
Very smart to stop. My neighbor mistakenly took out one of the hill bombers last week with his truck. The bicyclist was rushed off to the hospital. At that speed, there is just no room for mistakes or traffic.
I must be weird. I've always been afraid of dying from some stupid accident when doing something potentially dangerous, even when I was 16. Thankfully, it hasn't stopped me from flying gliders or rock climbing. (I did get some criticism from my peers for being too careful, after not going 20 meters above the terrain at 250kph, but the older folks seemed to rather comment that I had some sense).
I ride my bike to work every day. It’s a 25 km journey, so with 250km a week I think I ride quite a bit. The fastest I’ve ever gone was 58,8km (ran out of hill before I got to 60) and holy cow that was scary.
I can’t imagine getting to 80, must’ve been terrifying.
At around 2:45 either she speeds up quickly, or the car slowed down for a moment, and she was apparently millimeters from colliding with that little bar. Five seconds later, she's nearly pitched out the left side of the car (right side of the video).
From the perspective of the video it looks like shockingly small margins for error. The raw courage is remarkable, I'd never do anything like this!
The bike appears to have a device on it which allows it to collide with the bar of the car safely. It appears to me that she collides with it a bunch of times, both while accelerating and decelerating. This appears to be by design?
Definitely the risk of hitting the side of the fairing seems nontrivial though.
Dunno what they did to the brakes vs standard bicycle brakes, but I'd be very worried about activating them automatically at ~170mph. With those speeds and the winds, it wouldn't take much to set you tumbling across the ground. I would expect they only brake very carefully and gently until they get the speeds back down some.
At those speeds, even maximum braking is gentle - the blocks near instantly heat up and lose material. There's a reason why car and motorcycle use heavily cooled and much stiffer as well as more abrasive materials for brakes.
You have to be really careful to engage both front and back brakes at the same time though.
ITT: People talking past each other about 'highest performing males outperform highest performing females at almost everything' vs. 'average women are better at some things than average men.'
That article actually says that the average time for women is faster than the average time for men and that the fastest male times are still much faster than the fastest female times. The hypotheses they propose for the difference are either selection bias due to differing participation levels or possibly body fat percentage difference leading to greater bouyancy which specifically helps in swimming.
Camille's run wasn't particularly remarkable--about 10% slower than the men's 100 mile record.
Much more amazing to me is that this 10% performance difference holds remarkably steady for men and women's performance in a great range of distances, both running and swimming[0].
Yes, a world record is always remarkable in the general sense.
But in this specific context (discussing the coach's claim that women are "more capable of long-distance peak performance"), I wanted to point out that women's ultrarunning world records are not particularly better or worse than women's world records at other distances, even sprints.
Yep, I've heard the same about thru-hiking. Women might be faster at running 2000+ miles than men. It's for efforts measured in minutes or hours that the fastest men are faster than the fastest women.
Edit: I wasn't expecting my comments here to be so controversial
Do you have any source for this? It seems with such a small participation rate for thru-hiking, getting any sort of meaningful data about relative abilities would be unlikely.
Also this is not a long-distance endurance event, it lasts only a few minutes and should be more about technique, peak power output and engineering skill.
The fastest people in the world at 1500-metre runs or 5k bike time trials are never 45-year-old women.
I don't see how that's possible, given that men's times are better than women's times in all events. Just look at records, race times, etc. The trained men are dominating the trained women, and clearly the untrained women won't do better than the trained women. This pattern is consistent across all sports except possibly ultra-endurance events (way longer than a marathon equivalent).
The medical definition of "overweight" is pretty broad, and may include some people you wouldn't think of that way at a glance. But yeah, it's pretty bad.
Edit: Completely baffled why people are downvoting this.
I just meant that mildly overweight people wearing well-fitting clothes may not "read" as overweight to the casual observer. Some people think "overweight" means "obese," which makes the 70% figure more startling. It's still a major national health issue.
The average American male seems to carry more upper body muscle mass than, say, your average Indian male. You don't have to look like Schwarzenegger or The Rock to find yourself bumping up against the general guideline numbers.
My best guess is that your edge cases are going to come from people who are slightly overweight but still exercising regularly and have an overall healthy diet (as this WebMD page implies -- https://www.webmd.com/diet/features/can-you-be-fit-fat#1). These people may be healthier overall than someone in the "normal" range with a bad diet and sedentary lifestyle.
There's an interesting variety of record categories for bicycle speed; this is the very fastest one¹.
motor-paced/unpaced: do you have a motor vehicle providing aerodynamic assistance in order to reduce air resistance?
downhill/level ground: do you ride your bicycle on a flat surface or down a mountain?
faired/unfaired: do you have a canopy attached to your bicycle to reduce air resistance?
recumbent/upright: do you ride your bicycle lying down or sitting up?
indoor/outdoor: do you ride your bicycle outdoors or on a velodrome track?
¹ Wikipedia also describes a treadmill record in which the cyclist encounters no air resistance at all, only friction between the bicycle and the ground and mechanical friction within the bicycle. That record is 207.9 MPH (!).
Once they finished that phase of the run, the danger of a calamitous fall wasn't over: Holbrook and Mueller-Korenek had to work in tandem to slow down some 70 mph over a final mile, to reach an exit speed of 110 mph.
Yeah, once your only going 110 mph on a bicycle, the danger is pretty much over. /s
The truck in front is blocking the wind though, which is the point. Assuming she was going all out to fight the leftover wind, it probably felt like 40mph.
I wonder what sort of ridiculous speeds could be attained by a cyclist in a [long] vacuum chamber.
I suppose the athlete would need to wear an EVA suit (or a diving suit? the requirements are sort of between the two), so that'd be a bit of a damper on their peak performance, but still.
Of course, that sounds more like a skill involving reduction of friction and outputting as much power through the legs as possible than the more difficult act of also controlling a bike at those speeds.
You can forget the electro-magnetic cars Elon, just give me the vacuum tube and I'll jump on my bike. If I could sustain anything close to that in a vacuum tube I would probably ride rather than taking some cross country flights.
The treadmill record that Wikipedia mentions is probably comparable to what the vacuum chamber record would be, because there's no forward-to-back air resistance, only mechanical and rolling resistance, and a trivial amount of air resistance associated with the cyclist's leg movements.
I wonder if there's a non-trivial amount of air resistance due to the wheel spokes whirling around at whatever RPM is necessary to attain 200mph? In the real world, it's negligible, but at that high RPM it seems like it must account for something.
Yes, as the sibling says they'd be using disc wheels. I'm a bit surprised that for the OP's speed record they weren't - maybe they were more worried about crosswind wrecking the effort, versus absolute efficiency.
With rollers (what I'd think the "treadmill" discussed above actually is), and a normal road bicycle, you can feel, or at least hear, the resistance just from the spokes in a spoked wheel when you really get get them spinning "real world" fast.
On fancier road race wheels, the spokes are "bladed" for this reason - their cross section is flattened to minimise aerodynamic drag. Remember that when you're riding a bike in normal conditions, the top of the wheel is hitting the oncoming air at up to twice the speed of the bike. Though, there's also a substantial amount of appearance/marketing/armchair-engineering around...
Regular diving suits operate at ambient pressure so they're useless in a vacuum: you wouldn't be able to breathe and would lose consciousness in seconds. Pressure suits like what astronauts and high-altitude pilots wear are so bulky and stiff that cycling would be nearly impossible.
Plus it will save your nose. My cousin was in a bad high speed motorcycle accident and cracked his helmet. Slid a long way.. He lost a lot of skin on his toes, ended up having fused vertebrae, but his face was ok.
She said her thoat was covered in salt by the end of this high speed ride. needed a respirator.
I am not taking away from this feat because that is an amazing speed. Someone having the courage to stay on a bike going nearly 200 mph is incredible. I don’t want to get into the gender aspect of this either. My question is that it seems peculiar to even attempt a speed record under circumstances that are so completely artificial. Trailing a vehicle that blocks the wind? Having to be towed more than half way to the final velocity?
Sure it’s a record, but it isn’t one that reflects any real world scenario. I would be very interested in what the speed record is when someone gets on a very expensive well engineered bike from a stop and under ideal yet still realistic conditions is able to reach x mile/km per hour under human power only. I don’t mean this as snark either it just seems like there are infinite stilted scenarios where we can imagine some “world record” such as “world hang gliding speed record holder exceeds Mach 1 while tethered to supersonic plane”. Maybe I’m answering my own question here when I say maybe it’s about the engineering required to do this safely.
I also feel the same way about using reaction motors (jets and rockets) to set land and water speed records - they seem to fall into the rather arbitrary category of "let's do everything we can to go as fast as possible except put wings on on it."
Ultimately, though, it is even more about the courage to try it than the technology.
indeed- the idea that you can strap a rocket to anything to increase its velocity really only serves to advance things like braking and tire technology. That is, however, a valid pursuit.
Well the TDF is at least theoretically supposed to be run by folks who don't dope, train hard and do the entire ride under their own power. The fact that you mention it in the same vain as this record did make me laugh though since reality is about the same level of "fake".
Having a world record for something that requires so much skill and determination that it takes decades to beat it quite the achievement. Impressive by any measure. Congratulations to her!
> Moments later, Holbrook yelled out into the open air of the Salt Flats, "Beat that, Fred!"
Fred I assume is 72 year old Fred Rompelberg, who set the previous record 23 years ago. This challenge might be more appropriate 23 years from now :).
Makes me think of the contrast with Felix Baumgartner who in his 2012 historic jump intentionally missed the free fall time record by a few seconds to not take every single record away from the previous holder, Joseph Kittinger, who held them for 52 years.
"Felix Baumgartner intentionally missed the free fall time record by a few seconds to not take every single record away from the previous holder, Joseph Kittinger, who held them for 52 years."
Although this shows respect and admiration for Felix Baumgartner on one hand, overall it lowers the value of the game and of the players. The contests' value relies in its genuineness and it catches a cheap feel when some strong contender does not run in it wholeheartedly. Joseph Kittinger holding a world record for 52 years is a spectacular feat that won't loose any value if it was indeed unrivaled by contenders despite their best efforts all those years. That title won't, however, hold the same value from 52nd year further, knowing it lasts just because Felix Baumgartner decided to let it. Winning prizes are not charity.
This is not what I'm suggesting. Winning is not charity but you may feel you have reached your goal with the records you already won. Winning is also not about "winning everything". For example a football (soccer) match where you stop scoring after you have a reasonable goal lead is perfectly expected under "fair play". Nobody will consider it charity.
I just contrasted the behavior of one world record holder who sacrificed part of his performance out of respect for the previous holder as opposed to the world record holder who screams "beat that" at the 72 year old previous holder just moments after beating him. I find the second type of behavior distinctly more belittling for both. Especially when the other guy was 5 years older and using far less advanced technology, and also some very impressive lifetime achievements.
I think you're interpreting that very uncharitably.
An exhilarated rider, just learning she surpassed her own goal by a significant margin and who, I would wager, knows the previous record-holder, can say something like that without it being remotely cruel.
Maybe she is a sports jerk. I'd wager good money it was meant, and taken, in good humor.
> Makes me think of the contrast with Felix Baumgartner who in his 2012 historic jump intentionally missed the free fall time record by a few seconds to not take every single record away from the previous holder, Joseph Kittinger, who held them for 52 years.
That's what I call having a class and deserving my respect. Yelling some stuff about beating 23 year old record, well, has not. Materials improved tremendously, and out understanding of achieving high speeds too.
It's like topping some old Everest record speed ascent when materials got much lighter, critical gear more reliable etc. And then yelling at Messner to beat it. Not cool at all...
Generally I would agree with you but maybe they just know Fred in person and maybe he appreciates the joke?!
Maybe they were just loaded with adrenaline and couldn't help themselves.
However most probably they value the person holding the previous record and you just understood it in a too personal way. What I want to say is we shouldn't be too fast with judgements (in this case and in general).
This is insanely dangerous. One whiff of the slipstream and you are dead.
As for physical difficulty, the bike setup she uses takes about 1.5 watts per mph of rolling/gearing resistance, although the back end of the slipstream gives some forward pressure. The drag vehicle is likely the limiting factor.
Is it that dangerous? I thought motorcyclists wearing protective gear were safe if they fell slid to a stop. The danger would be from crashing into other things, but most of this place looks flat?
If she fell out of the slip stream, she wouldn't have fallen over. She would have been thrown off the bike by hitting the 175+mph wind. It would be like walking out of your house into a Category 5 hurricane. She could have been tossed and likely died.
Yeah, that's what I was thinking. A few times she wobbled and I thought how terrifying it must be.
I wonder if the slipstream would tend to keep her inside it - I mean, would she in some way be repelled back into the slipstream if she strayed towards the edges? Or is that wishful thinking?
I think it is unlikely. Firstly, in drifting into the slipstream, she would experience a powerful torque, twisting her away from the center-line (and maybe creating gyroscopic precession of the wheels around the bike's longitudinal axis). Secondly, the slipstream will be very turbulent. Thirdly, the speed is well above a human body's terminal velocity of around 120mph, so the slipstream is powerful enough to pick her up and throw her to the ground, especially given that drag goes by the square of velocity.
plenty of motorcycles doing 300 mph at Bonneville (there's even a Triumph mc named after the place). Her posture isn't ideal I agree compared to drag and speed trials bikes https://youtu.be/3Cq-DfTTPFw
These motorcycle drivers are continuously exposed to wind pressure though, in her case she would be suddenly exposed to it which probably would be not unlike hitting a wall.
In addition, her bicycle is not aerodynamic and likely weighs between 20-30 lbs, whereas a race a race motorcycle is very aerodynamic and might weigh between 400-500 lbs.
I'm sure the rolling weight of the wheels would dramatically impact stability as well.
Actually I've done this. You have to push your body out past the boundary layer before you jump outward. A lot of people do get blown back in, but I've also seen the diagonal running dive work at fairly high speeds.
I applaud this, but at some point "riding a bike" becomes a somewhat inaccurate and/or incomplete description of what's happening here. There's so much auxiliary stuff required to make this possible that it seems like a bit of a stretch to call this "riding a bike". The footnotes kind of matter.
My thoughs exactly. They are behind a car and bike specially crafted for this and they pulling the bike up to speed - probably because the bike is non-fuctioning under 100 kmph or so. Great technical feat but it's not "cycling as we know it".
From TFA: "Mueller-Korenek sat on a bike with gearing so steep that she needed to be towed to around 100 mph before taking over under her own power." So no, she didn't just maintain 184 MPH.
The semantics of it are silly and pointless to discuss, since she's not accelerating those extra 84MPH using only her own power. There's a lot of aerodynamic influences happening here and this is more of an engineering feat than an athletic one.
The GP is factually wrong, this isn't "semantics". Your comment moves the goalpost to "well the aerodynamics help". This is true: The slipstream moves at the speed of the car ahead, so it's like she has no headwind slowing her down. She still needs to accelerate 84 MPH (on top of maintaining 100 MPH). Think of doing this on a gym bike where you don't have headwind either. This is very much an athletic feat.
It's also an engineering feat, but again TFA: "As they targeted the overall record, their team revamped the same dragster that was used to set the men's record" -- they're reusing last time's engineering.
This record is like having a record for bench pressing with the aid of hydraulic lifts. How much do the hydraulic lifts help? How much is the person contributing? The whole premise just seems really stupid, and it's even dumber if they were to make the headlines "Woman smashes world record bench press at 23 tons". Just throw someone in Elon's hyperloop vacuum tubes on a bicycle fixed to the rails, make them wear a pressurized diving suit, and let them go to town. I'm sure they'd break 184MPH and it would be an equally pointless dick measuring contest.
Yes, she also needed to accelerate from 100 to 184, which (I am guessing) is a significantly lesser feat than maintaining a balance on a salt lake surface and keeping herself in 3 meters of a slipstream area. This is all remarkable, but the point was that this setup is probably not what most people would imagine when told of "a woman riding bicycle at 183.9 MPH".
Yeah, getting a relatively normal vehicle to drag an enclosure with the aerodynamics of a brick (it has to punch a big hole in the air otherwise it wouldn't shield the rider from wind resistance) at a little less than 200mph is somewhat of an achievement in itself.
It might be interesting to know about the technicalities of such things, like computational ones. The Liverpool group¹ that recently got hand-powered records did a fair amount of CFD modelling a few years ago, and presumably more recently (and somewhat restored faith in mechanical engineering students doing research computing).
I remember doing some calculations years ago and calculated that if one was capable of riding in a vacuum one could reach a speed of over 2000km/h based just on friction of moving parts and road
Would it be possible to build a bike like this but with multiple gears to get to speed from a standing start and not be towed? Is 100mph tow detatchmemt a required limit for the record?
I think you could, but you'd need a long way to get up to speed. The power needed to accelerate (Force=Mass*Acceleration) would be huge. I would imagine it would be a lot greater than steady state, where the only thing slowing you down is wind resistance. The windblock was clearly designed to minimize that force.
I don't feel comfortable going much of 80mph sitting in my car.. I can't imagine doing it on two wheels. I don't think my car actually can go that fast...
Well the power needed to get from 100 mph to 183 is a lot more than from 0 to 100, at least in kinetic energy terms which is proportional to velocity squared.
I think the main problem is that you'd be tired out getting to 100 mph, but that with the gearing so high it would be very difficult to start from a standstill without tipping over.
I thought about that too. I'm not sure how big spacing you'd need between gears so the jumps aren't too abrupt. You probably want something like a motorcycle transmission to handle the high speeds. Maybe something like the pinion gearbox but with much higher gears and larger spacing to get you to 200mph at a reasonable cadence.
The front chain isn't moving any faster or enduring any more intense forces than a normal bicycle drivetrain, so it can be replaced by an off the shelf road bike gear set. With a 30-speed drivetrain this could provide a low gear that's about the same as the high gear on a road bike, so it would probably be possible to get moving from a standstill. In the highest gear, you'd be able to go at least 160mph pedaling at the same cadence that was used to set this record. And that's just with the off the shelf components. A custom set of gears could probably stretch out the ratios enough to provide a high gear that's equivalent to the record-setting configuration.
Everyone is equal, but hey heres a WOMAN that did a thing!
I'm happy she achieved this, but the cognitive dissonance from HN is depressing.
That being said, I never knew these records were done with a draft vehicle. It kind of takes the human out of the equations to the point that I don't care if a man or woman set this record.
It seems like the pure record would be whoever has the land speed record in a bike unassisted by a tow and slipstream. I have more respect for whoever did that over some person that needed a mechanical advantage via a draft and a tow.
No, it's to eliminate aerodynamic drag, since nobody is strong enough to pedal against that anywhere near 180. It's awful hard to get a car to push against that. Nevertheless, going 180 mph on a bike is extremely dangerous. If you had any failure of the bike/tires, brushed against the slipstream, the towing vehicle suddenly speed up or slow down, you'd be dead.
I also expect the drag racer would need modification. They're heavily optimized for a few seconds at full power, not a controlled cruise at moderate power. You'd likely need an automatic cruise control setting for precise speeds, a much more effective cooling system, and a clutch that doesn't engage with a huge jerk.
That doesn't seem likely to me, because she doesn't pedal when she's being towed at the beginning. She only begins to pedal at around 0:30 in the video. So I conclude that there's a freewheel.
Someone might suggest that the extraordinarily high gear ratio means that the initial acceleration involves just a tiny foot movement, but I think it would be severely disproportionate to what we see -- one of the interviews referred to the bike moving 128 feet per pedal revolution (quoted elsewhere in the comment thread). Clearly the bike has been towed much more than 128 feet before a pedal revolution has taken place, right?
I would think a fixed gear under the circumstances would be very dangerous for various reasons, including the extremely long deceleration time at this speed and the extreme hazard of applying friction brakes. A fixed gear would mean that giving up the attempt (or even just ending it normally) requires a long period of continued effort to avoid injury and a very likely loss of balance.
I wanted to contrast this with velodrome speeds by pointing out that this is over 3× the unpaced velodrome speed record and that the unpaced velodrome record allows the cyclist much more overall control of the situation. On the other hand, I don't know for sure whether the motor-paced velodrome record (which is about 2/3 of Mueller-Korenek's new outdoor record) used a fixed gear.
It's fixed gear. It doesn't seem like she's pedalling at the start because the gear ratio is soo large, so large in fact the bike can't even be pedalled at speeds less than 15mph.
The pedals continue to be pushed forward when the rear wheel is rotating freely. With a freewheel, this shouldn't happen (the pedals can drive the rear wheel when they're moving forward but not backward, while the wheel can drive the pedals backward but not forward).
But I'm still confused about the lack of visible pedal movement during the initial towing part of the record video. It seems like she was towed more than far enough that the pedals should have needed to move visibly with a fixed gear.
That said, couldn't you just do a differential speed? Measure radar to the car, and from the car to the bike? With some extra math, I'd think you could easily establish her speed.
Though...I also don't think the radar is necessary. Just rpm of the tires would suffice. No?
The KHS bike she rode was a dragster in its own right. The low-slung, chopper-style bicycle is more than seven feet long and outfitted with 17-inch motorbike wheels for stability at insane speeds. It also demands a two-wheel drivetrain to propel the absurdly tall gear.
“The drive ratio is 62:12, twice,” said John Howard, Mueller-Korenek’s coach, who once held the motor-paced record himself at 152 mph back in 1985. “That’s roughly 488 inches, or approximately 128 feet per revolution. She’s traveling nearly 130 feet every time she turns those cranks. It’s pretty mind-boggling.”
Since I've had to convert several numbers to metric now to make sense of them, I though I'd put the conversions here for anyone else that's in the same boat:
183.9 MPH = 296.0 KPH (record speed, average over 1 mile)
100 MPH = 160 KPH (approximate speed at which tow rope detached and she began accelerating under her own power)
128 ft = 39 m (linear distance travelled per crank revolution)
More simply, it's a ratio of ~26.7:1 --- the wheel turns approximately 26.7 times for each turn of the crank.
Using some of the other numbers mentioned here, we can calculate that at her top speed of 296km/h she was pedaling at ~126RPM, and the wheels of the bike spinning at ~3377RPM.
If we knew the torque, or alternately the "stroke" of the crank and the average force she was exerting, we would also be able to find out her power output in W or HP.
Edit: some searching around reveals that 120-130RPM is usually where peak power is for cyclists, which corresponds with roughly where she was at top speed: https://www.ncbi.nlm.nih.gov/pubmed/17562069
...and it makes me wonder if she had another gear, would she be able to keep accelerating beyond that. She would've probably been producing 1-2HP at that speed.
So someone breaks a world record by a really big amount and the top two comment threads are virtue signaling about how unsafe it is to ride various two wheeled vehicles fast and to borrow the words of another commenter, people talking past each other about 'highest performing males outperform highest performing females at almost everything' vs. 'average women are better at some things than average men.' Way to go. This is supposed to be a tech message board. /rant over.
Now can someone tell me what the construction differences are about this bike that makes that speed possible. For starters a normal bike tire won't like that speed let alone for that duration. Is she using tubed tires? I can't think of any application where tubed tires go that fast at all let alone for that long.
Apparently it uses motorbike wheels, and it has a double reduction gear system. There is a cool section where the journalist tries to ride it without a tow-start, very difficult to peddle under normal circumstances.
Might want to reread the article. It's only towed by the car until it hits about 100mph since below that speed, it's not really possible to turn the pedals due to the insane gearing. Above that speed, the race car detaches and the bicyclist pedals up to 183.9mph.
There's also a "non motor-paced" category of records which does involve pedaling from a standstill to the maximum speed. Presumably involving many shifts. They are not surprisingly slower, because just as in driving a car, accelerating requires the most power, and maintaining speed much less. A multispeed bike would have more frictional losses in the gearing too. If she tried to get to 183.9mph from 0, on a bike with an appropriately large number of gears, she would probably be tired out long before she got to that speed.
I guess the real question is, how much of the propulsion (after the rope connection is detached) is actually from pedaling and how much is just a pneumatically coupled "tow line" from the car.
Still quite a feat to control a bike at that speed with near certain death so few inches away.
Does the higher air pressure from behind actually provide net thrust. If you neglect that you still have some air resistance, rolling resistance from the tires on the ground and various frictional losses in the bike. Overall, since the record on rollers indoors is higher (200 mph iirc) it seems being pulled being a vehicle isn't a huge benefit.
It's hardly a rounding error compared to all the drafting. Nobody who has ever ridden a bike fast in and out of a slipstream would waste much thought about that little towing assist at the beginning, it's almost comparable to the little push the official gives to send a time trialist down the ramp.
It would be a heck of a lot dumber for the purposes of setting this particular record fitting the weight of the not insignificant number (and range!) of gears it would take to let human legs accelerate the bike to that speed...
Remember, she is doing over 180mph at probably somewhere in the region of 80-120RPM at the cranks, that’s an _enormous_ gear to push.
It’s the same reason you don’t start your typical car in 6th gear from a standing start.
For what it’s worth, people do try standing start records using a car for a slipstream and a very large fixed gear, it typically limits most riders to ~100MPH. Given the huge jumps in cog size needed it’s hard to do multiple gears on a push bike for something like this without building pretty complex (and likely heavy) transmissions. You’re certainly not going to manage it on Shimano derailleurs...
I guess in a way it just saves time, she could have some set of gears to manually work up to that speed. Assuming you could fit that many gears on a bike, but yeah it’s not precisely what’s I’d expect either.
I think I understand where the comment is coming from. It's like saying the fastest car in the universe is the Tesla roadster in space. At what point does this become about semantics? Does getting hurled into space count as a car being fast? Does getting dragged by a car and letting something else roll along after decoupling count as being fast? The headline is misleading in that regard.
I'm trying to understand the magnitude of her accomplishment.
Based on the help she got from the car and the bike's unusual gearing, it sounds like her main athletic accomplishment was to accelerate a bike by 83.9 MPH.
> Accelerating a pedal-powered bike by 135kph / 83mph is a stunning accomplishment. I am flabbergasted that you don't see that as something notable.
I just don't know either way. I would imagine it comes down to how much time or distance she had to accomplish that acceleration.
Because without significant wind resistance, and with appropriate gearing ratios on the bike, honestly I just don't know what else would be physically demanding.
> As Holbrook accelerates, the cyclist will push 700 watts for more than a minute to stay inside the draft pocket behind the dragster’s fairing. That’s about what a Tour de France sprinter produces in the final minute of a stage.
The gyroscopic effect is not what causes a bike to balance, it's the arrangement of centres of mass around the pivot or steering. It is harder to maintain that balance at high speeds since small adjustments to the steering produce much quicker responses.
That's highly inaccurate. The gyroscopic effect is not everything, but it does get stronger at higher speeds. That's why even a simple wheel without any frame or steering mechanism will run mostly stable at high speeds. So when going at high speeds on a bike, it indeed is more stable than when going slow.
The article you link only claims that the gyroscopic effect is not everything stabilizing a bike.
Beside what has already been said, I'm pretty sure wheels turning at those speed cause an enormous amount of friction.
And they're spoked, that has to turbolence!
This is a really unproductive class of response to criticism.
It's unreasonable and pointlessly limiting to restrict criticism to people who can potentially replicate the results. Also the ad hominem aspect really sours the mood.
It depends on what it is a response to. If someone says that a particular feat is no accomplishment and easily replicable for essentially anybody (not e.g. in comparison to other participants), it doesn’t strike me as too unreasonable to call the person claiming it out on that.
Sports are different from, say, someone criticizing art that way, where an appropriate response to “I could have done that” is often “but you didn’t”.
But in this case that commenter did not say "anyone could have done it". My interpretation of that comment was that the actual accomplishment is different (and lesser in terms of athleticism) from what the headline suggests. Does that deserve a "but you didn't" rejoinder?
Is there any cycling record category that doesn't try to reduce wind? Time trialists use special bikes and gear to reduce the effect of the wind. Road racers try to be behind someone that can block the wind for them. This is yet another category with the same theme.
You're talking about reducing drag. There's a difference between trying to reduce drag and piggybagging behind something that almost complete eliminates wind, and perhaps even helps because of the way the air flows around the chute and creates a push effect behind it. Just the same as what's happening here: https://www.youtube.com/watch?v=tWwwuCK-3iQ
I disagree that this is even close to the same as other categories.
I'm not one to pay attention to such things normally, but the repeat gender and stupidity references in this thread seem to jump out, encouraging a vague sense of disappointment, and leave me wondering how the comments would look if it had been a man setting the record.
Motorcycle dragsters know not raise their torso off the bike around 120+ mph. Your body acts like a sail and you go flying off the bike. The high speed accidental dismounts in this sport will be interesting to watch.
You just serve as an air brake. As long as you're holding on it's not that big a deal on a sport bike. It sure helps with braking distance though since you can counter the lift of the rear should you need to emergency brake from such speeds.
Source: individual who has ridden liter bikes > 180MPH many times.
It's pretty fun and a great adrenaline rush, but holy shit it's dangerous. It's not like I was wearing protective gear, my polystyrene helmet and lycra wasn't going to protect me at that speed. All it would've taken for me to fuck myself up was a large stone or a nail in my tyre or even just speed wobbles.
I stopped hill bombing pretty quick. It's not really worth the risk.
The fastest I've managed on a flat is around 60-70 km/h, drafting behind a random car. That's also not safe, if the driver tapped their brakes, I'd go straight into them.
There's something so cool about going at car speeds, but without a motor.