tyrion

Only crash into soft things like haystacks and big piles of pillows.

daoswald

I've crashed something like three times in my life. None of them were substantially similar enough to be able to train for graceful landings.

The first was when I was a teenager. I don't know where I was looking but it certainly wasn't at the road ahead because I ran into the back of a parked truck.

The second was 11 years ago when someone door-ed me. The door opened, I swerved, and the corner of the door caught the edge of my shoe, ripping it opened. Nobody was hurt. I was.... angry.

The third was a year ago when I hit a boulder someone had chucked out into the road. Went down hard into the curb and skinned my elbows and knees badly. The crown of the stem even gouged my chest up a little. Front wheel was destroyed. I rode home on a bare, bent rim. I had to open the front caliper brake just to allow the rim to rotate. It was a wobbly, bloody six miles home.

They were each probably avoidable. If I had been paying more attention to the road ahead back in my teenage years I wouldn't have plowed into the back of an American steel pickup. If I had been riding a little more into the lane I would have been out of the door zone. If I had noticed the boulder earlier I wouldn't have hit it.

But in the case of the first event, there was no time to react.
In the case of the second event, I did react, which is why I got a sliced shoe instead of a broken foot.
In the case of the third event, one instant I was riding 17mph, the next I had been slammed to the ground on my elbows and knees and didn't even realize what was happening until I could hear the sound of flesh and handlebars skidding on the pavement. There was no evasive action to be taken. (I was riding at night with good lights, but that boulder seemed to spring out of the shadows).

In skiing you do practice falling as the first lesson. But falling is an every-day part of the sport, and once the skis pop off it's just a tumble on packed snow. You're not riding a contraption that puts your center of gravity a foot or so higher. With skiing you have a lot more warning that things are going south. People still break legs and injure their knees, but a more typical fall just involves the yard sale of equipment strewn up the hill. To me with cycling crashes are far less frequent, far harder to prepare for, and far more severe in their outcomes.

downtube42

I slammed into a guardrail at 35 mph, flew down a ravine, and landed on my head fracturing my C3. My leg caught the guardrail upright in passing, which ripped a nice L-shape into my thigh. I am, surprisingly enough, alive and headed for a full recovery. It's very difficult to say whether I avoided death by falling well, or nearly died by falling badly, since I have no memory of falling. I did land in blackberry briars, which was better than into the wooden fence a few yards right or the asphalt drive a few yards left.

What I intend to do differently in the future does not involve judo lessons, studying applied physics, or practicing falling. I intend to descend with greater care and not slam into guardrails at speed.

wphamilton

I should have remembered my policy to never explain physics to anyone who hasn't asked. My fault for getting him wound up.

DropBarFan

Once was pedaling hard off-saddle @ 15 mph (with loose toe clips) & the front wheel collapsed & by sheer luck I did a perfect roll over the handlebar & ended up on my feet at a trot, a passerby even remarked it looked pretty cool.

I suppose one can practice or learn by experience but my bad crashes have been into cars with little time to react. One would think pro racers are experts at crashing but there are so many ways to crash & the crashes happen fast so they still get broken clavicles etc.

Ounce of prevention is to slow up at intersections, sharp corners, downhill etc. Wider and/or lower-pressure tires probably stop faster in emergencies. Disc brakes stop quicker in the rain. Race announcer Phil Liggett warned against not using gloves. I knew a bike commuter that used a motorcycle helmet, don't know if due to a medical condition or caution but I had to admit it was much better protection in a crash.

woodcraft

I can think of a dozen+ crashes. Only one involving a car. Including only the most serious mtn bike crashes, & not any CX ones.

No serious injuries- 55 years. More substantial injuries (but still not that serious) from skiing, rock climbing, and volleyball.

smashndash

I’ll pitch in with a slight twist. There’s simply no way I can comment knowledgeably on how to crash. But you can do a few things to turn situations that other people consider “guaranteed crashes” into “saves” or at least “could have been a lot worse”. There’s actually a swath of scenarios that would cause a poor bike handler to go down and a good one to stay upright.

1) wheel overlapping or wheel chopping. For races and group rides, I would say this is by far the most common type of crash. I’m not gonna say you’ll be able to stay upright 100% of the time this happens, but you can get very close. Go to a beach or grassy lot and practice getting your wheel chopped. Don’t go too fast, of course. As long as you learn to steer away from the other guy’s wheel, you can save it.

2) HARD braking. Calibrate your hands/butt so that you let off the brake when you feel the rear wheel lift. Practice lifting the rear wheel with your weight all the way back. If you can brake this hard, and *then* crash, you’ll be a lot better off than if you immediately lock up and go OTB (one of the worst kinds of crashes in terms of breaking bones) or don’t brake very hard at all. An SUV turned across the road and nearly hit me head on. I slammed my brakes just hard enough to endo, but not to go OTB. Ended up tapping his front bumper (he stopped) and staying upright.

3) Get pushed around. Hard. You and a friend should go to a parking lot and get rough with each other. Try shoving each other, pushing their bars, pulling their shoulders etc. Ride side by side with someone, with one arm each on the other’s shoulder, clanging bars. I once hooked bars with someone midcorner in a crit. He pulled away from me and threw me deeper into the corner. But I stayed cool and upright by pulling away.

4) Brakes are death. Get really sticky tires, and I can promise you that, on a descent, the safer thing to do is almost always to lean it out. Grabbing a panicky handful of brakes midcorner is a recipe for disaster because of how instantly you can overwhelm the tire. It’s much more gradual of a fall (or even a nonexistent one) if you let Jesus take the wheel and lean.

5) Reinforce yourself. Unless you have huge ambitions, most cyclists can stand to gain some muscle/tendon/bone/ligament density. You don’t have to get huge. Just do high impact and high load exercises in very small volumes. This isn’t just a crash thing. It’s better for your overall health. Many people injure themselves doing mundane stuff, especially as they get older. Being flexible and strong will reduce the probability of a serious debilitating injury and will also expedite your recovery.

Feel free to disagree with me. Hopefully this isn’t too off topic.

79pmooney

Usually, you go over the bars because your front wheel has slowed. So , unless the fork crumples, the bike has little choice but to pivot over the slower moving wheel. Your head goes forward, yes, roughly parallel to the ground, but the bike seat goes up, taking your butt with it. Now your butt is higher than it was and has more potential energy to impart to your head when it slows as it contacts the ground.

smashndash

I think the easier way to think about it is dispersal of kinetic energy. The lowest impact crash is a low-side, because almost all the kinetic energy is dispersed by sliding (RIP skin).

When you OTB, your front wheel has locked but your kinetic energy is still within you. So it gets changed to rotational energy with the front wheel as a pivot. Now when you hit the ground, you’ll hit it dead on. No sliding. All the kinetic energy is going to get dispersed by your skull, teeth, shoulders etc.

bruce19

I can only opine based on my 40 yrs. cycling and my experiences as an MSF Instructor. For those unfamiliar with MSF, it stands for Motorcycle Safety Foundation. I would guess that in 99% of crashes, you will be on the ground before you can react with some kind of strategy to minimize your fall. If you are the other 1% and low side your motorcycle you would probably want to put yourself in a position to slide, assuming you are wearing leathers. On a bicycle I'm guessing sliding in lycra would be ugly. But, basically I don't believe anyone can actually see a crash coming and have enough time to prepare for it.

livedarklions

You're postulating a flight path that approximates an airplane glide slope. That's just not what happens, some of that speed-added kinetic energy will increase the impact of the first contact with the ground, the proportion depending on the angle to the ground when you land. Your forward momentum remaining after the initial impact can also result in bouncing, btw. There's a reason that planes flare before touchdown, that angle needs to be precise to keep the forward momentum from being completely stopped by the initial impact with the ground, and to let it be slowed in a controlled manner. I don't know about you, but the control surfaces on my arms and legs really aren't up to achieving that angle.

On what planet is one likely to be airborne on a bicycle on level ground long enough to even consider separating from the bike? That's a pretty neat trick on earth.

I've had a couple of wipeouts on level ground at 20+ mph, and in both cases, it's been a condition where sand or dust made the road slippery. I was on the ground before I knew what happened. In one of those cases, it was quite clear that the handlebars hit the ground first, and absorbed much of the initial impact. I ended up with scrapes, light bruising and finished the ride home. Not sure how I could have done better other than by avoiding the sand in the first place.

63rickert

You're thinking of one accident scenario and I'm thinking of another. I described my scenario. A boxed-in accident where no sliding across acres of open pavement is going to happen. In which case the best course of action is to step off the bike. It is possible to just step off the back of a bike. In the dream case you land on your feet and just walk away. More likely you fall, it's a low fall and not a horrible one, even with complete lack of judo and stuntman training. Instead of dreaming dreams about flying through space head on consider the possibility of stepping off the bike. Also consider that every accident or incident is not alike and one response does not fit all.

Considerable discussion here of catapulting. It occurred to me that I have witnessed riders catapulting upwards and have also witnessed riders catapulting on a flat trajectory, never getting higher than the 'bars they just went over. Then it occurred to me I'd seen both my wife and my brother do just that. So I asked them. They had the same answer, quickly and without thinking about it. As soon as it is clear that an over the bars accident is happening start to dive. You don't want to go up. So dive. Personally have never done that and would have guessed OTB is nothing but physics and the rider gets to do nothing about it. But I was wrong. Two riders quite near to me and they both know what to do and have done it.

Many accidents will occur where the rider has no agency. Has no chance of doing anything. If you make up your mind in advance that you can't ever do anything you won't. And then all accidents will just come out of the blue.

Have said it before. Number one accident I see is caused by not watching the road. Get off the phone. Get off the Garmin. Review all the data when you get home. Have none of this electronica on the handlebars. Phone stowed securely for emergency use. And turned off while riding.

wphamilton

I'm serious, I'm not "arguing" physics with people who haven't studied it. I take this off-topic "why do airplanes flare" as a question. The flare reduces airspeed by increasing the frontal aspect, and produces lift due to the angle. Neither of which have much to do with a bike crash.


I will give you a suggestion though. If you truly want to solve the ballistic motion and get an idea of impact, start with a vector diagram in terms of momentum.



You've seen videos of over-the-handlebars falls surely. Hit a curb at full speed, the bike is impeded but you still have momentum. If you're not clipped in and not holding on deliberately, you'll naturally separate from the bike. And frankly your first instinct should be to push off, not hold on.


The only thing that holding on does for you in over the bars is to help start your body rotating before the roll. You need to turn loose as soon as that happens or the timing is thrown off and you'll land flat, not rolling.

indyfabz

Anything is possible here on Bikeforums.

cyccommute 

You are correct that crashes are over rapidly. The point of a "strategy" is to engrain what to do before you crash. If you tell yourself enough times to not stick out one of your appendages in a futile attempt to catch yourself before hand...like your whole lifetime beforehand...you are less likely to throw out your hands or stick out a leg when you do crash. Same with relaxing during the fall.

I don't think about these things during crashes but I am mentally prepared while I ride. I have, on occasion, noticed things during a crash, however. I lost my grip on a handlebar during a jump and distinctly remember my hand floating above the bar and thinking "This is going to hurt."

In a crash with a car, I remember sliding across the hood of the car, the color of the hood (blue, kind of oxidized), the shape of the car (not necessarily the model), yelling "Oh, s(excrement)!" at the same time that the guy in the car was yelling the same thing and the black of the pavement as I slide off the car, the blue of the sky as I rolled and my handlebar bag sliding into the front suspension of another car with a substantial "thump" ( although that doesn't do justice to the sound). It didn't take a second for all of this to happen but everything seemed to happen in slow enough motion to remember the details.

I'm not saying that I had anytime to plan in that seeming slow motion event but the lessons I'd drilled into my head for years before the crashes took over. In the case of the car, I hit the ground with my right knee but was tucked and tumbling so that my shoulder took the rest of the impact rather than hitting the ground flat on my chest or, even worse, head down. I know I rolled because the only other point of contact with the ground was a scuff mark on my right shoulder.

cyccommute 

Ah, the classic Bike Forums "I won't explain something because the other person is an idiot" gambit. You can't explain the physics because your physics are wrong. No physicist will tell you that a fall of your center of mass from roughly 4 feet will kill you while an impact on a flat plain at 100 mph won't. It simply doesn't work that way.

If you are so confident about your physics, teach us. Hiding behind "you wouldn't understand" reflects more on you than on us.

wphamilton

No offense intended. I'll give you the same suggestion as livedarklions: if you want to solve for the impact, start with a vector diagram in terms of momentum.

cyccommute 

The bike pivots but the center of gravity continues in a straight line until such time as gravity arcs it downward. On a bicycle, the center of gravity is in the middle of the rider's body instead of nearer to the wheels of the bicycle as would be the case in a motorcycle or car. Your butt isn't the center of gravity. You don't arc upwards.

Even if you were to arc upwards, the change in the center of gravity's height would be very small. The energy imparted by falling from the center of gravity is going to be very small compared to the energy imparted by forward momentum.

cyccommute 

I've been in many, many, many crashes. In not a single one have I been able to "step off the bike". First and foremost, I'm clipped in which I have found through years of experience is far safer than having my feet free. Second, my saddle is far to high to just "step off". I would have to have time to lift myself off the saddle and step back. Third, if I have than kind of time to plan to step off, I'm going to be fighting to stay upright and/or avoid whatever I'm going to crash into.

And while I agree that no crash is like another, there are things you can do in any crash to lessen the potential damage. Again, don't "brace for impact" or try to catch yourself once you fall. The crash might not hurt any less but if you break a bone it can hurt a whole lot more.

livedarklions

Sorry, but I used to let go of the handlebars in those situations, and all it got me was injured hands. If I "ride" the bike into the ground, I find there's a better than even chance that some part of the bike is going to make the initial contact with the ground and absorb a large portion of the impact. If I let go, generally, my hands hit first, and I'm kind of attached to them.

The other aspect of this, which I think you're ignoring, is that it's often quite difficult to determine exactly when the situation has become unrecoverable. There have been several times where I thought I had lost control of the bike where I was able to pull it back in by holding onto the handlebars. There isn't a lot of conscious decision making going on there as far as how to regain balance, but I'm quite sure if I was focusing on timing a "let go" maneuver, I wouldn't have the mental wherewithal to avoid the ground in the first place.

Yes, airplane flares reduce speed, but they also adjust the attitude so the plan lands on the correct landing gear in as close to horizontal position as possible. And if horizontal speed doesn't matter, why does a plane need to reduce speed in order to land safely? All this "I know physics stuff and you don't" isn't covering for the obvious violations of common sense you're committing. It's quite revealing that you've been asked twice why you can't just step out of a moving car if you're correct, and all you do is tell us we're not qualified to discuss this with you.

cyccommute 

How about you give us a vector diagram for momentum. I can run the vector diagram for momentum in my head and the vector for the momentum downwards is infinitesimally small compared to the size of the forward momentum...especially in your 100 mph scenario. You are the one making the claim, show us how it works.

cyccommute 

Some of us have studied physics. You are wrong in your assumptions.


And your first instinct is wrong. Instinct also tells you that you should put your hands out to try to stop the fall and/or protect your head. That works well for our monkey brains and walking speed but our monkey brains fool us when we get faster than walking speed.

Additionally, you aren't going to "roll" all that far. If you let go of the bike, chances are that the bike is going to travel further than you and it will hit you, risking further injury. Holding onto the bike provides at least a little crumple zone so that the body doesn't take the full brunt of the impact. If nothing else, hanging onto the bars keeps you from putting your hands out.

wphamilton

I agree with this. You can react in time to mitigate the impact of most, but not all crashes, provided you've either trained in falls or experienced enough crashes to have ingrained some reactions.


I think the stumbling block is that people are more familiar with reaction times while driving - experts tend to use 1.5 seconds as a standard between perceiving a threat and reacting to it (such as braking). Or tested at almost 2.5 seconds in some cases. Between a bike unexpectedly out of control and hitting the ground is much less than 1.5 or 2.5 seconds. So, I think, they look at those times, think of bike crashes, and decide it's impossible.


There is a fundamental difference though, because crashing and falling involves kinesthetic stimulus, invoking the somatosensory cortex resulting in significantly faster reactions. IF you're not consciously processing, evaluating and deciding etc.




Hint: these are not scalar quantities.

caloso

Boxed in during a crit, riders in front of you touch wheels and go down. You have nowhere to go except into or over them. Your chances of crashing yourself approach 100% so you do what you can to protect yourself.

livedarklions

In a box-in accident, I'm putting my efforts into changing the direction of the bike to try to make the blow as glancing as possible and also hoping for a space to open up at the margin. The last time this happened to me, I was screaming so loud that I was able to get the driver to change course at the last possible millisecond, and the collision never occurred. At the speed I was going and the nearness to the vehicle, jumping off the bike would have been suicidal. And this occurred when a driver cut across four lanes of traffic at a high speed to illegally swerve into the breakdown lane directly in front of me, so please don't try to pin this one on me.