Bicycle Safety - The Math of Speed

General Discussion about electric bicycles.

Bicycle Safety - The Math of Speed

Postby DrkAngel » Thu Aug 04, 2011 7:28 am

Faster is Safer!
My Sister-in-Law just can't understand, why I feel that going faster, on a bicycle, is safer. "30 mph!" ... "You're gonna kill your self!". ...

I feel it necessary to prove that, up to the speed of surrounding traffic, faster is safer. Let me try a mathematical approach.

First, let me qualify;
1. My riding is in an urban area and 95% of the streets-roads are 30 mph limit.
2. I ride on the right side of the road, going "with traffic", as is the legal method.

For ease of math - Let's figure a 10 mile trip, w/traffic @ 10 cars per minute.

30 mph traffic:

At 10 mph -
60min x 10cars - 1/3 (for 1/3 speed of cars) = 400 cars passing you at 20mph.

At 15 mph -
40min x 10cars - 1/2 (for 1/2 speed of cars) = 200 cars passing you at 15mph.

At 20 mph -
30min x 10cars - 2/3 (for 2/3 speed of cars) = 100 cars passing you at 10mph.
AND, cars have twice the time to notice, and avoid, you! (vs 10 mph).

At 25 mph -
24min x 10 cars -5/6 (for 5/6 speed of cars) = 40 cars passing you at 5mph.

At 30 mph -
20min x 10cars - 3/3 (for 3/3 speed of cars) = 0 cars passing you!

(Math is simplified - but "sound")

When you consider that many bike accidents are directly related to passing cars, especially in a "road" environment, then 20 mph would be (4 times safer than 10 mph) x (2 - twice the time the, approaching, driver has to see biker) = 8 times safer @ 20 mph, compared to 10 mph!

Most impressive is that each speed increase of 5 mph reduces the volume of passing traffic by 50%!

A__hole factor! Everyone might agree that, possibly, 1 in 100 motorists are AHs toward bicyclists, (Conservative Estimate!), Going 10 mph you'll get passed by 4, only 1 @ 20 mph and at 30 mph you might never encounter 1.
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Re: Bicycle Safety - The Math of Speed

Postby John in CR » Thu Aug 04, 2011 9:37 am

Speed kills. Just look how speedily they killed the forum.
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Re: Bicycle Safety - The Math of Speed

Postby Pure » Thu Aug 04, 2011 9:39 am

Also don't forget, that the impact of a car is lessened with the faster you are traveling. The only deciding factor is how much more the ground hurts at 30 MPH vs 10.
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Re: Bicycle Safety - The Math of Speed

Postby jimw1960 » Thu Aug 04, 2011 9:56 am

The logical conclusion of your analysis is that we should all just buy morotcycles. Going faster and faster on bicycle frames not designed for such speed brings in additional risk that offsets the advantages.
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Re: Bicycle Safety - The Math of Speed

Postby John in CR » Thu Aug 04, 2011 10:23 am

Electrics belong only at mobility device speeds according to the owners of this forum.
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Re: Bicycle Safety - The Math of Speed

Postby TonyReynolds » Thu Aug 04, 2011 10:55 am

John in CR wrote:While I agree that faster can be far safer, I wouldn't agree to reducing it to numbers in that manner, and you definitely can't do 2X for driver time seeing you.

I don't believe you become drastically safer until you match or exceed traffic speeds. It only applies if out on the roads is where you ride. I get passed by a car maybe once a week, and half the time it's at a time and place of my choosing and deem to be safe. I believe I'm far safer than the average cyclist in the area, but not necessarily thousands of times safer, but it's a big enough difference for me that I wouldn't ride at all if I couldn't match traffic since there's near 0 biking infrastructure here.

I feel nearly as safe as in a car. Sure I'm far more exposed, but as long as I pay extremely close attention to my surroundings from traction issues and obstacles that are issues for bikes not cars to being more prepared by assuming no car sees me until I have evidence it does or I'm out of the danger zone, then being more exposed and less easily seen is mostly offset by being a far smaller target with more room to escape driver errors.

There's a flip side to every coin though. At speed any accident will prove far more costly, so you have to ride mistake free. What is slippery and what isn't is probably the most difficult thing to get right 100% of the time especially when it comes to emergency braking.


This same rational applies when I jump on my motorcycle, however, ABS brakes help in slippery conditions.

Motorcycle - Bicycle, either one requires what Airforce pilots call 'situational awareness'. You just HAVE to be aware of your surroundings and what's going on to stay 'safe' on the streets. Far, far less room for error when you're not surrounded by a steel cage...

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Re: Bicycle Safety - The Math of Speed

Postby MadRhino » Thu Aug 04, 2011 11:12 am

I'd say faster is safer, until you crash, then it's not that safe anymore. :mrgreen:
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Re: Bicycle Safety - The Math of Speed

Postby DrkAngel » Thu Aug 04, 2011 11:32 am

John in CR wrote:While I agree that faster can be far safer, I wouldn't agree to reducing it to numbers in that manner, and you definitely can't do 2X for driver time seeing you.

With most all vehicle vs bicycle accidents, the driver claims "I just didn't see him".
2x the time the vehicle is approaching the bicyclist, allows much more free time, that the driver has, between sipping coffee, reaching for doughnut, texting, adjusting the radio, etc., to notice the biker.

Twice the time, to see a biker, could make a great difference!
Last edited by DrkAngel on Thu Aug 04, 2011 5:39 pm, edited 1 time in total.
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Re: Bicycle Safety - The Math of Speed

Postby dannyboyohyeah » Thu Aug 04, 2011 12:04 pm

I learned somewhere that hitting anything at 30mph that isn't moving (like the earth) or a parked car....is the same as jumping headfirst out've a 2nd story window and thinking you can break your fall with your hands and arms. Ok...that is one point of awareness that is pretty shocking.
Then, as more per the usual bike accident, you ad the momentum, mass and immovability of a car that hits you....say...at 20mph. (combined vectors of speed.) That is a very gentle accident, by accident standards, I'd say. Having survived a motorcycle crash at 45mph and having 147 fractures, 12 surgeries, and dying three times....I'd say I am more aware of and concerned about safety than most people, by far. Most people simply cannot and do not imagine or know what it's really like to have a serious crash. The stats on bicycle deaths is not forgiving, and nearly ALWAYS involves a vehicle. You can....if you have much greater than average awareness, control yourself...but you can never control the driver of another vehicle, except to stay well out've their way, or block their way in an obvious manner and hope they are humane about that. But you are still guessing.
Outrageous lighting at night, safety gear, and sharp awareness are your best tools for survival. Athletic ability is sort've set for each of us at a level we cannot improve too much. Some roads are vastly more dangerous than others...because of poor or absent paved shoulders to ride on, general speed of traffic, and temperment of the local population. I think the best way to stay safe is to realize THIS factor and be honest with yourself about it. And do not risk, regularly, beating the odds of an unsafe roadway. Please be more careful than you imagine is necessary. You do not yet quite know how much your life and health and happiness depends upon it.
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Re: Bicycle Safety - The Math of Speed

Postby wineboyrider » Thu Aug 04, 2011 12:17 pm

I do feel safer at faster speeds, but if you don't have decent brakes (ie disk brakes) anything over 30mph is less safe not more. Situational awareness is what driving anything on 2 wheels requires. I feel safer on my Honda 150 elite than in my car. Why? Because, when I am on my scooter I have to be more alert and aware of A#$ hole drivers that don't see :roll: :roll: :roll: :roll: :roll: :roll: you. It's part of the exhilarating experience of driving 2 wheeled vehicles IMHO.
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Re: Bicycle Safety - The Math of Speed

Postby nuevomexicano » Thu Aug 04, 2011 1:11 pm

wineboyrider wrote:I do feel safer at faster speeds, but if you don't have decent brakes (ie disk brakes) anything over 30mph is less safe not more. Situational awareness is what driving anything on 2 wheels requires. I feel safer on my Honda 150 elite than in my car. Why? Because, when I am on my scooter I have to be more alert and aware of A#$ hole drivers that don't see :roll: :roll: :roll: :roll: :roll: :roll: you. It's part of the exhilarating experience of driving 2 wheeled vehicles IMHO.
8)


I feel that good brakes are more important than anything else. I've ridden some really fast two wheelers, like a 1000cc Ducati, and some really slow scooters, like a stock 50cc Honda Ruckus. For me, its all about owning one's lane as opposed to using speed to get out of trouble. I own my lane with a regular pedal bicycle and slow speeds for safety. Speed has never got me out of a hairy situation with a car since those are usually a car turning left in front of me or one passing me, then slowing down quickly and cutting me off with a quick right turn. Those situations are all about swerving and emergency braking. Speed hasn't yet got me out of a car cutting me off.

Going as fast or faster than traffic hasn't always made me safer. I've been riding my 50cc scooter and my electric bicycle faster than the speed limit, sometimes 12-15mph faster, and still had drivers try to pass me not because I'm going slower than prevailing traffic (I was sometimes passing cars myself), but because they simply assumed a small bike was slow and needed to be passed.
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Re: Bicycle Safety - The Math of Speed

Postby Solcar » Thu Aug 04, 2011 1:11 pm

Pure wrote:Also don't forget, that the impact of a car is lessened with the faster you are traveling. The only deciding factor is how much more the ground hurts at 30 MPH vs 10.


Indeed, a very important formula involved in the math of speed is k=(1/2)mv^2. The kinetic energy increases in proportion to the square of the speed. (k is the kinetic energy, m is the mass, and v is the speed of the bike.
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Re: Bicycle Safety - The Math of Speed

Postby dogman » Thu Aug 04, 2011 4:39 pm

Having done my share of crashing at speeds from 5 mph to 50 mph, here's a couple of non theoretical real world observations.

1. Hit something square on, it really hurts. It hurts the bike, and if you yourself hit stuff square on it hurts you. No avoiding it. Brakes help a LOT, since the slower you hit something square on, the better. However, even 5 mph impact dead on can still hug you up but good!

SO DON'T DO THAT!

2. Hit something much more obliquely, and you slide off it, or if the earth itself, you slide down it. Much much much much prefered to the dead stop, as in the leap out a window example.

So how the hell do you turn #1 into #2?

Master the laydown. Don't hit that car head on, slide into it feet first, and do it with no hesitation when you must.

Master the skidded rear tire. While laying on plenty of front brake, but not locking it, lock up the rear tire and steer with your ass, and counter steer with the front tire. That is, point the front tire where you want to go, no matter what kooky angle the whole bike may be at. Adjusting where you lay it down by just 2 feet can save your ass. Ideally, you park yourself between the rows of cars, or to the left of that hugger that just left crossed you. Typical manuver, you just got left crossed. You can brake and hope you hit him slow, but you won't because he's moving towards you doubling the impact speed. Or lay a sliding skidded turn to the left, just missing him, and the rows of cars going straight ahead. Thread the needle between onrushing cars going straight and the car that just left crossed you.

Riding in dirt is the best place to master the skid turn, then take it to asphalt and practice it there.


30 mph, is in my opinion, a pretty safe speed for any decent bike. Brakes and frame flex tolerable. Above that, you really need quality, or motorcycle. But if you don't know how to skid a turn or do a laydown ,you are in danger at 30 mph. You are just going to have to take it like a dog when a car pops into your path at 30 mph. It's not if, it's when. If you don't have bike handling skills, you might want to slow down, and get the hell off roads with 30 mph speed limits.

I totally agree that not getting passed so much is a good thing. Just be aware, that when following a car at speed oncoming cars don't see you. You WILL get left crossed more, just like you do when riding a regular motorcycle. So you must be ready for that hazard, now that you eliminated another. What you do by speeding up, is simply trade what whacks a bicycle for what whacks a motorcycle. And don't forget to add your speed to the speed of the car that whacks you, for that kind of accident. 8)
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Re: Bicycle Safety - The Math of Speed

Postby LI-ghtcycle » Thu Aug 04, 2011 5:43 pm

I agree that keeping up with traffic CAN be safer and cause you to be passes less, but there are always the brain donors that have to pass you because you "must be going slower on a bike", and depending on where I am riding, speed can be more dangerous.

Perfect example is traveling on the bike lane along a busy road, and either the car coming out of the parking lot or turning into one will cross my path harmlessly at normal bike speeds, but at 25+ I am going faster than they expect and they turn in front of me thinking I am going slower, particularly on a higher MPH road, in this case 40MPH.

Now if I were to be traveling at 45 with traffic, no problem, but in the situation that I am not, I have two choices:

A) Go faster than they expect, greatly increasing my risk of being hit or:

B) Slow down and traffic flows normally.

Of course I would love to be able to go 25-30 MPH in the bike lane along a higher speed road, but I am much less in danger and MUCH less frustrated going closer to 15 - 20 MPH and not having as many conflicts with traffic.

Now, that being said, where I can keep up with traffic, I do, and have a good experience there too.

In the end, it really makes no difference who has right of way, more that I have no bumpers and am going to lose every time I get into a accident with something bigger. :wink:

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Re: Bicycle Safety - The Math of Speed

Postby Kurt » Thu Aug 04, 2011 6:03 pm

I have found that when riding my bike at +30mph the average car driver and pedestrian isn't expecting you to be travelling that quick and they pull out in front of you. Then there is a surprised look on there face as you almost run up there ass. If you were riding a motorbike people expect it to be Doing 40mph + and give you space.

I feel its great to have a bike that can do 40mph with strong acceleration. But riding at 20mph would be safer and just use the power to get you out of a dangerous situation.

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Re: Bicycle Safety - The Math of Speed

Postby ZOMGVTEK » Thu Aug 04, 2011 6:59 pm

It really just depends on where you ride. I tend to ride on the shoulder of the road, and most roads on my way to work have ample space. However, drivers entering or exiting side streets and businesses are less likely to see me if I am traveling fast, so I tend to go about 20 MPH. At that speed, most people see me, and recognize me as a bicycle. When I'm going 40 in the middle of the road, I have a lot of people pulling out right in front of me. I prefer to ride 30 MPH in 30 zones, following a car. The car in front of me cant really present much of an issue for me, and people tend to get out of the way. The vast majority of the time, people also give me ample following distance when I ride in traffic at higher speeds. Nobody is likely to pull out between two cars, regardless if they see me or not, and I dont have to worry about people passing me.

Basically, I ride with traffic at 30-40 when there is no shoulder, and ride as far over as possible at 18-22 MPH when there is.
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Re: Bicycle Safety - The Math of Speed

Postby dogman » Fri Aug 05, 2011 6:38 am

You guys have seen what I have. At some point, your speed changes the hazard from bike type hazards to motorcycle type hazards.

The right and left crossing traffic that either didn't see you, or expected you to be going 12 mph definitely increases. Somewhere around 30 mph, you aren't going to stop in time anymore, no matter how good your brakes are. Now you are in motorcycle territory, where your survival depends on being capable of choosing the place you crash. Slide off the side of that car, or smack into the hood. Choose the slide if you can. 8)

Again, the single most effective thing you can do, is ride a safer route, even if its a few miles longer. My route has all kinds of little safe cuts in it. Avoiding a few big intersections, detouring around a 1/2 mile section of dangerous 4 lane street by taking to the parking lots. etc. Of course, on the back streets the speed limit is 25 mph. I have a section of route where I could travel fast safely, and go 30 mph. Few driveways, and no left crosses on a on way street. 30 is ok with me, its the limit for mopeds in my state.
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Bicycle Safety - The Math of Speed - Road Math

Postby DrkAngel » Fri Aug 05, 2011 11:57 am

Open Road Edition

I've demonstrated how faster is safer, in a 30 mph traffic environment. But "On the road", with higher speed traffic, is where the most concern about passing vehicles exists. How does speed effect your risk in a 60 mph traffic situation.
First, let me qualify;
1. Riding is in an rural area and 95% of the roads are 55 mph limit.
2. I ride on the right side of the road, going "with traffic", as is the legal method.

For ease of math - Let's figure a 10 mile trip, w/traffic @ 10 cars per minute.

60 mph traffic:

At 10 mph -
60min x 10cars - 1/6 (for 1/6 speed of cars) = 500 cars passing you at 50mph.
Driver has 7 seconds to notice & accommodate biker.

At 15 mph -
40min x 10cars - 1/4 (for 1/4 speed of cars) = 300 cars passing you at 45mph.

At 20 mph -
30min x 10cars - 1/3 (for 1/3 speed of cars) = 200 cars passing you at 40mph.
Driver has 9.5 seconds to notice & accommodate biker. Cars have approx. 1.4 times the time to notice, and avoid, you! (vs 10 mph).

At 25 mph -
24min x 10 cars - 5/12 (for 5/12 speed of cars) = 140 cars passing you at 35mph.

At 30 mph -
20min x 10cars - 1/2 (for 1/2 speed of cars) = 100 cars passing you at 30 mph!
Driver has 12 seconds to notice & accommodate biker.

(Math is simplified - but "sound")

When you consider that, in "open road" conditions, most bike collisions are directly related to passing cars, then 20 mph would be (2.5 times safer than 10 mph) x (1.4, the time the, approaching, driver has to see biker) = nearly 4 times safer @ 20 mph, compared to 10 mph!

30 mph would be (5 times safer than 10 mph) x (2, the time the, approaching, driver has to see biker) = 10 times safer @ 30 mph, compared to 10 mph!

Note: Some of the math is approximated, fairly accurate, but will modify if deemed necessary.

Most impressive is that every bit of speed increase greatly reduces the volume of passing traffic and therefore increases the safety factor!

A__hole factor! Everyone might agree that, possibly, 1 in 100 motorists are AHs toward bicyclists, (Conservative Estimate!), Going 10 mph you'll get passed by 5, only 1 @ 30 mph.
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Re: Bicycle Safety - The Math of Speed

Postby dogman » Fri Aug 05, 2011 1:42 pm

Couldn't agree with you more, for more rural riding where the right and left cross opportunites are few.

In that situation, for sure going faster can be safest. Texting mofo might even look up soon enough to see you. But what is really key, is it gives you more time to do your endo into the ditch avoiding having him tag you.

On the other hand, I much perefer doing my riding the bike off the road and into the ditch much slower. At 15-20 mph, I might even avoid going over the bars. I've been run into the ditch at 50 mph, while descending a big hill. Pretty sure it was deliberate by the driver. Watched him swerve at me to run me off the pavement. Riding off into the ditch at 50 mph was,,,, entertaining. Might even say stimulating. A nice ditch I didn't crash ,but wow that frame was bending like rubber.

Which brings me to the other thing. No car, or truck, EVER passes me that I didn't eyball the sob. That way the relative speed of the car doesn't matter. No way I'm allowing it for him to hit me. NO WAY. But for sure, when you ride faster, you buy a potentially life saving extra few milliseconds for you to dodge for the ditch. Definitely a pain in the rump to eyball 300 cars an hour, but whatever the number, you must eyball every single one.

We get a few bike fatalities every year localy. Nearly always the situation you describe, 45 or more speed limit, driver hits the bike from behind. In a way, always partly the riders fault. Didn't eyeball that driver and take evasive action.

Does trusting drivers not to be drunk, texting, spilling the coffe etc make sense? hell no.
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Re: Bicycle Safety - The Math of Speed

Postby scotticeberg » Fri Aug 05, 2011 10:27 pm

Getting hit sucks. I don't ever want to do that again.

Sometimes I take the ENTIRE lane. Sometimes I take the sidewalk. Sometimes I ride the wrong way down the road(not often). It all depends where I am riding.
Whatever keeps me safest. It's an art.

In San Diego taking the lane, or taking the sidewalk, all depended if I was traveling uphill, or downhill. Sometimes there were bike lanes. Downhill I might hit 40mph. Uphill, in some places, I was off the bike and walking.

In Detroit it is whatever goes. More towards the city there are enough under utilized side-streets that I have the road all to my self. Out in the suburbs its an anything goes 'Mad Maxesquean' gauntlet of sidewalks that stop and start at random, bike/ped paths that make no sense, and motorists who rarely see a cyclist, and act like it.

We have some nice rail-trails here in Michigan, not really practical for commuting purposes, however.

We need a national bike highway system....so I can go fast, and rarely have to worry about getting creamed by some moron in a car/truck/bus/semi.
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150lb Biker vs 3000lb Car

Postby DrkAngel » Mon Aug 08, 2011 11:20 am

Any direct impact by a car will, (almost), instantly accelerate a biker to, (very near), the vehicle speed, regardless of biker speed, or direction.

Math based on rear impact, at various speeds

C=Car
B=Biker
"Result" is the, post impact, resulting speed for car & biker both.

3000lb C (30mph) vs 150lb B (stationary) = 30mph impact = 28.5mph result
Initial impact comparable to fall from roof of 3 story building, onto hard car
Damage=probable broken bones, severe internal & head injuries etc.

3000lb C (30mph) vs 150lb B (10mph) = 20mph impact = 29mph result
Initial impact comparable to fall from roof of 2 story building.
Damage=possible breaks, internal injuries, concussion etc.

3000lb C (30mph) vs 150lb B (20mph) = 10mph impact = 29.5mph result
Initial impact comparable to fall from roof of 1 story building.
Damage=possible sprains, bruises etc.

3000lb car @30mph could be completely stopped by head on collision with 150lb biker @600mph, (near Mach1)!

Sorry, ... got carried away by math, it can be fun, ... maybe not for that biker tho ...
Last edited by DrkAngel on Mon Aug 08, 2011 12:24 pm, edited 2 times in total.
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Re: Bicycle Safety - The Math of Speed

Postby Doctorbass » Mon Aug 08, 2011 11:49 am

now some fact from my side :

I drove 11 000 km on ebikes since 2007.

average speed 25-30mph
max speed 112kmh

max speed in trafic 45mph

Accident with car: ZERO

accident on dirt in the forest : .. two.. was moderate...



We also must specify THE ACCELERATION !!

On my side i'm 100% convinced that with a resonable skilled ebike driver, aceleration decrease the risk of accident!

When you are on the front of all cars when they all start from a stop.. that avoid you to being hit by a car that is turning on that intersection!!.. while normal cyclist are stand up on the pedal to try accelerate slowly na dhave more chance to be hit by car that want to turn!

In my case, it bnever happen.. Once the light turn to greeen, i'm far away from the cars that start acelerate behing me!

believe me... Acceleration is safer than speed :wink:

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Impact From Behind - Best Scenario & Solution!

Postby DrkAngel » Mon Aug 08, 2011 12:23 pm

Absolutely the best solution to a rear impact scenario requires good speed capability, constant awareness, and one piece of specialty equipment.

First you want to be traveling, as closely as possible, to the speed of the approaching vehicle.

Second you must have an awareness as to the velocity, angle, mass and surface composition of the vehicle. Sets of 4 mirrors, or more, recommended, if possible, arrange into a stereoscopic, full 3D configuration.

Thirdly, and most importantly, the one piece of specialty equipment! "Cyclists Downunder", (based, possibly, in Australia?), has begun marketing their "Octopi" line of cyclewear.

Just make sure that you are struck squarely from behind. If you are about to be hit, quickly swerve and position yourself directly towards the center of the vehicle, the car should knock the bicycle from under you and you should roll gracefully onto the hood and, or, windshield, where the Octopi suction cups should keep you safely secured. (Tip: As soon as you get stuck to the vehicle, rip off one, or both windshield wipers! Some drivers will use them to try to knock you off. You can also beat them on the roof to get the drivers attention, in case he is sleeping, or just doesn't notice you.) Hopefully the car will come to a gentle stop and you can then safely get off. Much safer than rolling down the road at 30 mph or bouncing over the roof and landing, "who knows where"! (Tip: Please do not anger, or insult, the driver! You will probably need their help getting unstuck from the car!)

Warning! Speed is important! 20 mph bike speed is optimal to be hit by a 30 mph car.
Slower can result in fairly severe injuries.
Faster and you might not be bounced onto the top of the car, you might have to jump backwards, timing is critical! Warning! Be careful, some a__hole drivers will approach like they are going to hit you, then ... slow down, just before impact. If not aware you might jump, and miss, ... then where would you be? ... Embarrassed! ... ???

Large trucks can be very tricky. Most don't have a nice hood to get stuck to.
1. Ideally, you must be going 10 mph slower than the truck.
2. Timing is critical, you must jump straight up just as you are being run over.
3. You must hit the windshield squarely, with enough body, to stick. Grills-radiators don't work well with suction cups!

This is a skill! Like any skill it requires practice. You should have a friend try to run you down, a few times, just so you can get good at being safer.

Oh, ... Make sure you have a good supply of bikes handy.


P.S. Be prepared for being hit by the, proverbial, "Redneck Pickup". Keep an Armageddon bag handy, on your bike. Recommend couple bottles of water, sun screen, some granola bars, "Space blanket" ... anything you might need in case they drive around with you stuck to their hood, for a few days.

Disclaimer! You must read "Epitaphs of the Downunder Cyclists", before attempting this "solution"!!!
Last edited by DrkAngel on Mon Aug 08, 2011 12:38 pm, edited 1 time in total.
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Re: Bicycle Safety - The Math of Speed

Postby Uncle Ron » Mon Aug 08, 2011 12:33 pm

DrkAngel,

It's been a while since I've seen such a well done and amusing put-on as the "Octopi" cycle wear post. But take care or you'll have some fools start practicing for your extreme sport. (g)
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Re: Bicycle Safety - The Math of Speed

Postby Uncle Ron » Mon Aug 08, 2011 12:44 pm

Kurt wrote:I have found that when riding my bike at +30mph the average car driver and pedestrian isn't expecting you to be travelling that quick and they pull out in front of you. Then there is a surprised look on there face as you almost run up there ass. If you were riding a motorbike people expect it to be Doing 40mph + and give you space.

I feel its great to have a bike that can do 40mph with strong acceleration. But riding at 20mph would be safer and just use the power to get you out of a dangerous situation.

Kurt,

A most sensible post that I heartily concur with! On the other hand there have been lots of sensible posts on this thread that are well worth heading, particularly in how to deal with various types of riding situations. It always a combo of safety/speed/acceleration. Best to have all three if you can, but to always remember that speed can kill and maim whether with e-bike alone or in crossing paths with another vehicle. Dogman's "eyes on the idiots" is most appropriate, because it keeps your mind in the safety game and may give you that extra split second that's the difference.
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