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Well...think of it this way: Lets say theres a car taking a turn too fast and its gonna crash into the wall. Would u rather be strapped to the hood of the car or strapped to the trunk?

Id rather be on the trunk. My body will have the same momentum regardless, but this way I would be using the car as the "shock absorber" to cushion my impact.
If you figure out how little the difference is, I think you'd reconsider this. The only difference to your internal organs, and bones in the scenario you describe is how fine the paste that was your body will be.

The crumple zones on a car are designed to absorb about 10 MPH of kinetic energy/foot 1 foot crunched in car, it hit at about 10 MPH.... 2 feet= 20, 3 = 30 etc. The car crumples, because there's about 3,000 lbs of mass involved. When the car comes to a stop, and you hit the trunk...... you don't have the mass to make the car crumple in.

The only differential in speed would be how much the nose of the car crumpling slows down before chassis you hit the back. If you are both doing 60, and the car hits a cliff and stops completely.... you're hitting the trunk at 60. 88 feet per second.

For a general reference on what that sort of speed means--- if you jump out of a second story window, you will hit the ground at 25 MPH. 36 feet per second.

Jump off a 100 foot tall building. You'll hit the ground at about 60 MPH.

As they say, it's not the fall that kills you; it's the sudden stop at the end.

Personal 'crumple zones' are limited to being useful over speeds that nature could expect people to hit -- 10-14 MPH.

Best not to hit anything, going faster than that.

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The crumple zones on a car are designed to absorb about 10 MPH of kinetic energy/foot 1 foot crunched in car, it hit at about 10 MPH.... 2 feet= 20, 3 = 30 etc. The car crumples, because there's about 3,000 lbs of mass involved. When the car comes to a stop, and you hit the trunk...... you don't have the mass to make the car crumple in.

The only differential in speed would be how much the nose of the car crumpling slows down before chassis you hit the back. If you are both doing 60, and the car hits a cliff and stops completely.... you're hitting the trunk at 60. 88 feet per second.
Uuuh, so the argument used previously about strapped to the trunk or strapped to the hood is, honestly, pretty dumb.

Crumple zones are designed to reduce the sudden-ness of deceleration. If you stop from 60-0, it's the rapidity of the STOP that causes your brain to get all whacked about inside and all your organs to gank-up against the insides of your skeleton. A crumple zone allows that deceleration to happen slightly slower, but it only works because you're strapped into the inside of that box.

If you're on a bike, there's no 'gradual slowing' associated with the bike slamming into something before you do. There's no energy absorbed. There's you, travelling at 60MPH, then you stop. The fact that a bike smunched in front of you does not cause you to decelerate more gently, sorry.

No, laying the bike down is not ever better, it does not protect you, it does not cushion you.


Keep the bike on the rubber, use your brakes. Keep it up and on the brakes even if you're going to collide. Slow down as much as possible, then collide if it happens. This is the best way to bleed energy, and the best way to reduce your collision speed/force.
 

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Any crumple zone in front of u is still a lot better than u taking a direct hit yourself.

U cant argue with that. Thats the point I was trying to make with being strapped to the front vs back of the car.
 

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Any crumple zone in front of u is still a lot better than u taking a direct hit yourself.

U cant argue with that. Thats the point I was trying to make with being strapped to the front vs back of the car.
The only reliable crumple zone a rider has is their own body. Armor won't improve the situation by more than a very few MPH. No such thing as an Iron Man suit........Downey would have been thin layer of paste on the inside of the suit many times over.

Your heart, liver, lungs, kidneys, etc., all hang on a thread.... veins and such. Rip them free, and bleed out. 200 gee should do it. Your helmet protects you brain from about that....... which is generated by a vertical drop of 6 feet, onto concrete.

Take what chances you see fit. It's you choice.
 

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Any crumple zone in front of u is still a lot better than u taking a direct hit yourself.

U cant argue with that.
Except that's exactly what I'm arguing. A motorcycle that impacts before you do is NOT a crumple zone for you. You're in no way slowed down by hitting after it does. As far as your body and G forces on deceleration are concerned, there's no difference if you hit a car or a wrecked bike at that speed.

U cant argue with that.
 

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What the heck are you guys even arguing about? :cuckoo:

Anyway, I'm more curoius about the crash damage, especially regarding frame slider mounting points.
 

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Apparently crumple zones dont really exist :O
Crumple zone? :O

I get what your saying. Crashing and having the bike in front of me would make me feel better than just flying face first into an immovable object. Don't know if it will do any good against wall's but might help against cars. At least as a placebo effect. :)

________

Ultimately I think motorcycle armor is the most effective way to avoid some of that direct energy.

Here is an example of a functional crumple zone in action, featuring Loris Baz, using leathers/ armor specifically designed to absorb impact that would otherwise be transmitted directly to the rider's body.

Here's some video from Loris Baz's crash in Sepang. The airbag suit obviously serves as a "crumple zone" of sorts.

http://www.youtube.com/watch?v=on2mgiv4TxA

Here is some impact data.

Alpinestars Releases Loris Baz Crash Data | Cycle World

"Just exactly how intense was the crash though? Incredibly so, suggests the data, which confirms that Baz was running a staggering 180 mph when he first lost control of his Desmosedici GP14.2. He held on for another two seconds, but was eventually launched from the bike and landed on the ground 60 milliseconds later, with the highest energy impact recorded at 29.9 g on his left shoulder. The French rider then slid for a total of 6.6 seconds, Alpinestars says, adding that, “Despite the speed and level of impact force associated with the crash, Loris was able to walk away and resume testing.”
 

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Apparently crumple zones dont really exist :O
A crumple zone on a car, only works if the people in the car are restrained. If the car comes to a stop, and they don't...... they're still going just as fast as they were, and will come to the same complete stop as the car. It's that sudden stop at the bottom we keep talking about.

The seat belts, the air bags, the telescoping steering column, the safety glass, the roll cage, the design of the seats themselves, and the padded dash all work with the crumple zones to reduce the gee loading -- they spread out the time it takes for the occupant to come to a stop. And the people in the car still come out with serious bruising where the belts restrain them, and burns form the air bags (if not shrapnel). Injuries are a LOT worse, without seat belts in use. All that padding and energy control goes right out the window. Most people that die in car accidents are the ones who get ejected from the car...... and that's 99% of the time because they weren't wearing a seat belt.

This is why it is so important to put infants and small children into car seats...... a 25 MPH impact with a wall will make them hit the dash, or the seat back, or the windshield just as hard as if you had tossed them out of a second story window.

No car surrounding you....... no crumple zone. Just your body. Back to the statistics -- almost all motorcycle impact accidents occur at < 30 MPH. The person operating the bike didn't account for all the variables, and couldn't scrub off enough speed, or maneuver the bike to avoid the impact. A glancing blow is far more survivable than a direct impact with a stationary object. That might only cost you a few broken bones.

If the impact speed exceeds about 40 MPH, it doesn't matter how good the safety gear is........ odds of survival go down drastically. A 3- 4 story fall.

You can't wrap yourself in enough bubble wrap to slow your body enough to survive that. Way past 200 gee.
 

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Crumple zone? :O

I get what your saying. Crashing and having the bike in front of me would make me feel better than just flying face first into an immovable object. Don't know if it will do any good against wall's but might help against cars. At least as a placebo effect. :)

________

Ultimately I think motorcycle armor is the most effective way to avoid some of that direct energy.

Here is an example of a functional crumple zone in action, featuring Loris Baz, using leathers/ armor specifically designed to absorb impact that would otherwise be transmitted directly to the rider's body.

Here's some video from Loris Baz's crash in Sepang. The airbag suit obviously serves as a "crumple zone" of sorts.

http://www.youtube.com/watch?v=on2mgiv4TxA

Here is some impact data.

Alpinestars Releases Loris Baz Crash Data | Cycle World

"Just exactly how intense was the crash though? Incredibly so, suggests the data, which confirms that Baz was running a staggering 180 mph when he first lost control of his Desmosedici GP14.2. He held on for another two seconds, but was eventually launched from the bike and landed on the ground 60 milliseconds later, with the highest energy impact recorded at 29.9 g on his left shoulder. The French rider then slid for a total of 6.6 seconds, Alpinestars says, adding that, “Despite the speed and level of impact force associated with the crash, Loris was able to walk away and resume testing.”

Baez went down on a straightaway, and ran into nothing but the 'smooth' surface of the track. His actual fall that resulted in the ~30 g was from roughly the height of the saddle of the bike. From there, it seems like he got to slide without any tumbling, or thrashing around. Extremely lucky.
 
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