Wearing backpack - pros vs cons

[Mintbread]

There was a post a while back about someone's backpack tearing off an arm, but I have a hard time believing that, as the tensile strength of thread (stitching) is substantially less then that of the human arm.

I would put my money on the backpack every time. Nylon is a lot stronger than ligaments, tendons and skin.

[scan]

It has to be one of the most common items for simple transportation of items when riding a motorcycle. If you need to carry a few things, a backpack or courier bag seem like the easiest choice.

On the safety part of the discussion, I guess there is a chance you could come off the bike and the bag would attached to a part of the bike and drag you around like a ragdoll. If that worries you too much than you can do tail bags or tank bags.

[Sev]

There was a post a while back about someone's backpack tearing off an arm, but I have a hard time believing that, as the tensile strength of thread (stitching) is substantially less then that of the human arm.

I would put my money on the backpack every time. Nylon is a lot stronger than ligaments, tendons and skin.

Nylon thread is not. And that's the weak point in any sewn item. I've pulled straps bottems zippers and all sorts of other things off of my backpacks over the years. And invariably it was not the cloth that broke, but the stitching. Considering there's three places where the average backpack strap is sewn on. Plus those plastic clips designed to hold one part to the other, I'm willing to bet that the backpack would braek first if it got caught on something.

[Malice]

They also say that wearing a large helmet is more likley to cause whiplash that will break your neck.

There will always be an alternative viewpoint on safety vs function.

[Sev]

They also say that wearing a large helmet is more likley to cause whiplash that will break your neck.

There will always be an alternative viewpoint on safety vs function.

Who is "they"?

[bok]

one of "they" posted this on a michigan votes site:

The tempeture in a helmet can reach 130 degrees or higher,this will impair my reaction time. It adds more mass to my head creating more force on my neck which can fracture. The extra weight also causes fatique.
If a helmet is so safe, why do 30 states allow the freedom of choice?

Abate Member,
Jim Garron

"they" are all over the place... the idea is that the weight of a helmet transfers force to the neck in an accident...i don't buy it personally but there are stats that can be used to back up both sides depending on how you read them[/url]

[Mintbread]

Nylon thread is not. And that's the weak point in any sewn item. I've pulled straps bottems zippers and all sorts of other things off of my backpacks over the years. And invariably it was not the cloth that broke, but the stitching. Considering there's three places where the average backpack strap is sewn on. Plus those plastic clips designed to hold one part to the other, I'm willing to bet that the backpack would braek first if it got caught on something.

I am not sure what sort of backpacks you buy but mine simply don't fall apart.

Have you ever tried to pull the entire shoulder strap off you bag with one almighty pull, and succeeded? If not then your argument holds little weight.
The design of "good" backpacks gives the straps immense strength because of the amount of stitching based on which direction it would be pulled under load.

Considering your elbow or shoulder, they are simply bones resting up against eachother with muscles attached to them designed to make them bend and not to counter straight pulling forces, hence why dislocations are not uncommon.

If you tied a rope to your wrist and one to the strap of a "good" backpack and pulled each with equal force there is no doubt that the arm would go before the strap.

Keeping in mind:
http://www.snopes.com/horrors/freakish/disarmed.htm

[dieziege]

This is going to strike some as an odd viewpoint... but...

Being "loosely attached" is generally survival-positive... in other words, it is an evolutionary advantage to have parts that come off rather than staying attached to the core parts (head, torso, legs) of a human.

At a small scale, look at human skin... it comes apart very easily. Far more easily than cotton cloth. Why? You can't say it's because skin is inherently weak because horse skin isn't so weak. Well... for humans, survival means protecting the head, neck, and torso more than anything else... and if a predator has a claw in your skin you want to be able to pull away even if it means ripping the skin. With a horse... well, it is weak relative to the normal predators horses can get away from, but more to the point they are a lot more dependent on keeping their limbs and bodies intact than humans are.

This extends itself into the modern world in strange ways. For example... wearing gloves while using rotary power tools is generally considered very bad form. Why? Because if your bare hand comes in contact with a circular saw blade or snags on the work spinning in a lathe you'll probably just get a cut (though perhaps a nasty one)... if your glove gets caught in the same tool it can draw your hand into the tool up to the wrist. People have had their hands ripped off by lathes because they were wearing gloves and that gave something strong to catch on the spinning work piece and start smashing bones and pulling flesh apart. Even latex gloves (which come apart very easily) are considered questionable.

As you move up in scale... well, would you rather lose a hand or lose an arm? Lose an arm or lose your upper body?

Of course, while that's a good survival strategy when dealing with predators and table saws it ain't so hot on a motorcycle... we should all be wearing clothes that are designed to hold our parts together... gloves, leathers, et cetera. These clothes protect us from the likely hurt... flesh being ground away because it isn't held together very strongly. On the other hand, their strength can, if the clothes snag, can cause us serious hurt... a helmet that passes the "doesn't roll off your head" test is a helmet that could potentially decapitate you if it managed to get snagged on something as you slid along the ground. A boot that protects the foot by staying on securely could cause damage knees and hips and bones if it snagged.... so an effort is made to prevent snagging. Motorcycle outfits tend to have smooth outsides, sometimes with low-friction slider patches to prevent injury just from being slowed down too quickly.

If your backpack has a similar design constraint... smooth and snag-resistant... you don't have much to fear from it as far as limbs being pulled off. It might cause problems if you were trying to ride under something by ducking forward but didn't account for the backpack height... but that's more likely to happen off-road and is frankly rider error.

All that is left is the fear of landing on the load... and frankly that can happen with a tank bag or anything else. There's a video around of someone riding along and having a car go out of control in front of them... they went over the front of the car, flying 15 feet or so... and their tank bag went with them. They landed curled around the bag. Could as easily have landed on to of it.

[Tarzan]

Just to add my thoughts...

I've been wearing an 80ltr back pack almost every day to work for the last 15,000 miles or so now.
It makes a big difference in high winds - to the point that I won't ride anymore if it looks too windy outside.
Any adjusting straps on the back pack need to be tied and knotted to stop them flapping around. A loose strap whipping against your helmet at 70mph becomes extremely irritating very quickly - as I discovered.
The back pack seems to reduce my fuel effieciency slightly (52mpg without the back pack - 50mpg with the back pack).
It also makes riding in higher temperatures a little more uncomfortable as it adds another layer of insulation.

Last year I crashed at around 50mph with my back pack on. It didn't seem to make any difference to my injuries but since it's packed with clothing it might have softened the impact with the road.
I always take care to ensure that anything hard or breakable is well packed inside my clothing and I always wear a back protector underneath my leathers anyway.

My final thoughts - If I had the money I wouldn't use a back pack - I'd get a tank bag or panniers.

[Sev]

In order to tear off an arm the strap itself would need to wrap itself around the arm. I think it'd be far more likely that it would slip off and tear the skin away from the arm then completely sever it. Remember with a properly adjusted backback the arm loop/hole thing is several times the diameter of your arm. What happens when you tug on some one's backpack? It comes straight back into the shoulders.

So what you're saying is... you think a backpack can dislocate a shoulder, then tear through all the skin, muscle, and connective tissue including triceps and biceps, two of the larger muscles in the body.

Unless the strap wrapped tight around the arm, it'd merely strip the skin off any location, should it get stuck on something at high speed.

And that's assuming the backpack doesn't break.