Another crash report

#1
This is another crash report. This was the first crash in my 12 years bike history. I have not thought of such vulnerability of a bike before and thought this should be shared to all of bike lovers. I by the way have joined TCC some years ago and was active in bike riding but has been more interested in marathon and trail running for the last two years.

What happened.
Please see the photo of the spot. I was slowly moving and tried to go on the paved bike path, but there was a different level between the bike path and the ground. I hit this part and my rear wheel was lifted up and landed on my head. I was luckily wearing a helmet and did not get hurt my head. But my neck got shocked and injured in cervical cord. Consequently this affected the functions of my right arm. I now can do most of my daily movements with my right arm, but lost some muscle power of my right arm.
accident.jpg

Right after the accident, I was sent to a hospital and stayed there for one week without moving my head. Then, moved to another hospital near by my house, staying there for two weeks, receiving rehabilitation.

I was not moving too fast at the time but still experienced such an accident. I suppose this is due the center of gravity. A road racer is very light. Mine is 8Kg. And it is toward the front position. As you can see the image, the center of gravity on a road racer is high and of front. This is obviously different from the one for mama chari. Mama chari is heavy and position is behind.

I was surprised the rear wheel so easily move upward. With this experience, I just wanted to warn all of the road bike riders on this fact. It is very easy to turn over. Once you get injured on your neck, it could mean paralyzation of your arms, legs and whole body.

There are tons of risks in our whole life. This may be one of them, but it will be good to know there is such an risk in advance.

Happy bike life to you all. I will be indulged in running for a while.

Minoru Arai
 

thomas

The Crank Engine
Nov 1, 2005
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#2
Arai-san, I'm very sorry to read about your accident! I wish you all the best and a speedy and complete recovery.

And thanks for your warning, I hope you will enjoy cycling soon again.
 

kiwisimon

Maximum Pace
Dec 14, 2006
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#3
Minoru, i wondered where you went. I really enjoyed your loong touring reports.
Please get well as soon as possible and I wish you a complete and full recovery.
Thanks for the warning, i saw a crash this morning on my ride less than an hour ago. Racing bikes are built for speed not safety.
take care
 

StuInTokyo

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Dec 3, 2010
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#4
Really sorry to hear about your crash, I'm happy to hear you are recovering!

When I go over bumps like that I take my weight off the seat and stand on the pedals and try to lift the front wheel over the bump, but of course if you did not see the bump, you can't do that.

hoping for your quick recovery!
 

GSAstuto

Maximum Pace
Oct 11, 2009
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#5
Arai san - hope you are feeling better! I had a 'header' accident this winter but managed to avoid such serious injury except broken ribs - which was painful, but not dangerous. This dyanamic is quite interesting - when front wheel is suddenly stopped, the kinetic energy will provide just enough torque to rotate the mass (you and the bike). Like you note - if your center of mass is forward more, then the torque required to rotate it is less. Like Stu said, if you could suddenly lift yourself from the saddle, then center of mass is instantly moved backward and also the torque-time increased for rotation. Or, by using only rear brake - then chance for the wheel to continue to roll over the bump is possible.

What happended to me was I slipped on my bars with alot of weight forward and unintentionally pressed the front brake lever as I slipped hard. So, as the bike stopped my weight went more forward - pushed harder on the brake and rotated faster - all within a few hundred milliseconds. (I was on fixed gear, btw. And if I didn't have to have the silly front brake, this would never happened)

On road-bike this can be bigger problem - because many rider prefer riding 'on the hoods' - so they are naturally pre-disposed to press brake harder as the event occurs which subsequently accelerates the braking force -> kinetic energy transformation -> header!
 

GSAstuto

Maximum Pace
Oct 11, 2009
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#6
@Kiwisimon - anecdotally - the term 'Safety Bike' was coined to refer to all bikes that have nearly same size wheels compared to 'Ordinary Bike' which had the large front wheel / small rear wheel primarily due to the issue of 'headers'.
 

trad

Maximum Pace
Dec 4, 2006
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#8
arai-san: very sorry to hear of the accident. i hope you recovery quickly. I hope had an MRI to find out how badly the spinal cord is pinched and where. If you need somone to talk to pls let me know (i had survery to remove a back disk between c3 and c4 after losing nearly almost all movement in arms and legs, and know how scared you must feel)

pls get well soon
 

Mike

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Sep 24, 2007
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#9
Arai San, I was shocked to read about your accident and how easily at low speed things can so wrong. Thanks for the warning and I wish you a speedy recovery. Hang in there.
 

joewein

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Oct 25, 2011
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#11
I hope you'll make a full recovery soon!

One difference between mamachari and road bikes is also the tyre pressure. Softer (and wider) tyres can make it easier to climb over an obstacle rather than be knocked over (one reason why MTBs have fat tyres).

High tyre pressure was probably a contributing factor when I crashed in January while trying to climb from the road over a sloped kerb onto a side walk at too narrow an angle and too high speed.

I am really careful about the speed and angle now when I have to climb minor obstacles and get up from the saddle using my legs as suspension to soften the impact.

The less suspension effect you have from tyre deformation or leg travel, the higher the momentary forces resulting from impact with an obstacle.
 

Forsbrook

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Feb 13, 2008
399
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#12
Minoru,

Thanks for the update.

I was really sorry to hear about your accident.

Your report will help send a reminder to all of us and that we shouldn't take each ride for granted.

I hope you make a full and speedy recovery.

I,like Kiwisimon,was also wondering where you had disappeared to.

Hang in there and try your best.
Hope you are pounding the pavement soon,be it on foot or on a bike.
 
#13
Minoru, i wondered where you went. I really enjoyed your loong touring reports.
Please get well as soon as possible and I wish you a complete and full recovery.
Thanks for the warning, i saw a crash this morning on my ride less than an hour ago. Racing bikes are built for speed not safety.
take care
kiwisimon, my next destination was Shimokita-penninsula during this Golden week. Obviously this will not happen. Anyway, I will be touring someday.

Minoru Arai
 
#14
Really sorry to hear about your crash, I'm happy to hear you are recovering!

When I go over bumps like that I take my weight off the seat and stand on the pedals and try to lift the front wheel over the bump, but of course if you did not see the bump, you can't do that.

hoping for your quick recovery!
I know this is what I do normally. But an accident happens. It is the nature of accidents.:eek:uch:
 
#15
Arai san - hope you are feeling better! I had a 'header' accident this winter but managed to avoid such serious injury except broken ribs - which was painful, but not dangerous. This dyanamic is quite interesting - when front wheel is suddenly stopped, the kinetic energy will provide just enough torque to rotate the mass (you and the bike). Like you note - if your center of mass is forward more, then the torque required to rotate it is less. Like Stu said, if you could suddenly lift yourself from the saddle, then center of mass is instantly moved backward and also the torque-time increased for rotation. Or, by using only rear brake - then chance for the wheel to continue to roll over the bump is possible.

What happended to me was I slipped on my bars with alot of weight forward and unintentionally pressed the front brake lever as I slipped hard. So, as the bike stopped my weight went more forward - pushed harder on the brake and rotated faster - all within a few hundred milliseconds. (I was on fixed gear, btw. And if I didn't have to have the silly front brake, this would never happened)
Your description on the mechanism of the accident is exactly right. I am glad you did not get too serious injury, anyway.:)

Minoru Arai
 
#16
arai-san: very sorry to hear of the accident. i hope you recovery quickly. I hope had an MRI to find out how badly the spinal cord is pinched and where. If you need somone to talk to pls let me know (i had survery to remove a back disk between c3 and c4 after losing nearly almost all movement in arms and legs, and know how scared you must feel)

pls get well soon
Thank you for the suggestion. yes, I had MRI twice. Since I work for a medical company, sales reps in my company had good information on who and which hospital I should go. Then, I was able to see an experienced physician. He explained clearly what happened. I have to do rehabilitation anyway.

Minoru Arai
 
#18
Minoru,

Thanks for the update.

I was really sorry to hear about your accident.

Your report will help send a reminder to all of us and that we shouldn't take each ride for granted.

I hope you make a full and speedy recovery.

I,like Kiwisimon,was also wondering where you had disappeared to.

Hang in there and try your best.
Hope you are pounding the pavement soon,be it on foot or on a bike.

Oh, I went to downtown area of Tokyo to see Cherry blossom or Hanami with my friends at the day and had the accident on the way back home only 2 Km away from my house, after 130Km ride.:mad:
 

Philip

Speeding Up
Feb 15, 2007
765
7
38
Setagaya
#19
Hi Arai-San,

I am sad to read about your accident. I hope your arm recovers soon. Thank you for sharing the circumstances.

Cheers,

Philip