Kevlar jackets?

[Shiv]

Would kevlar be any better for the impact than leather is? How about the skidding? I know leather is great for the skidding but that the impact is the hard part to protect from. I was thinking kevlar for its bullet proof purposes. I don't plan to be shot while riding the bike (though in this town, who knows) but thought the same impact protection that stops bullets might help when you hit the ground.

Any reason to that rhyme or is it apples to oranges?

[Shorts]

For impact, well, some kinda armor would work. Sure you'll get blunt force, but, you'll be spared from a lot of the abrasions and cuts.

Kevlar on those draggin' jeans is suppose to do well from the advertising I've seen.

I wouldn't go out of my way to buy a kevlar jacket if I already had a good leather one.

[d2mini]

Go to the motorport.com website and click on the "save your hide" link.
I had their Air Mesh kevlar suit and I sold it only because it was a bit too bulky for me. But man do you feel invincible in it.

[jonnythan]

Would kevlar be any better for the impact than leather is? How about the skidding? I know leather is great for the skidding but that the impact is the hard part to protect from. I was thinking kevlar for its bullet proof purposes. I don't plan to be shot while riding the bike (though in this town, who knows) but thought the same impact protection that stops bullets might help when you hit the ground.

Any reason to that rhyme or is it apples to oranges?

Kevlar by itself does not give any more impact protection than leather.

Even low-level body armor, which would have trouble stopping any bullet other than small-caliber handgun rounds, has 15-30 layers of Kevlar, and most have steel, ceramic, or titanium plating over critical areas such as the heart.

A fairly effective "bullet proof vest" will have metal or hard ceramic plates covered by 2-3 dozen layers of Kevlar. The Kevlar provides some impact protection, but mostly is effective because it resists hot, blunt objects like bullets from directly penetrating the cloth better than most fibers because it's so incredibly heat-resistant and strong. The metal or ceramic plates are there to distribute impact forces and provide additional intrusion protection. Without the metal plates, even rounds that don't penetrate the vest typically leave massive blunt force trauma under the impact site because.. well, think about it. You're stopping a bullet with layers of relatively soft cloth. The bullet won't penetrate your skin, but it's not much different from getting whacked with a 15-lb hammer.

Anyway, long story short, you could make a jacket out of Kevlar, but it would need to be fairly thick for it to give the same amount of abrasion resistance as leather... and it wouldn't achieve the goal you're trying to, which is impact resistance. The stuff is just cloth. It's strong cloth that's difficult to penetrate, but it's still cloth. You need actual armor for any impact resistance, whether in the form of EVA or super thick Kevlar plating or what have you.

[Sev]

Kevlar by itself gives very little abrasion or impact resistance. In the thicknesses that you will typically find in motorcycle gear it's not for impact resistance, only abrasion.

However in order for it to work well as abrasion resistance it needs to be mixed with some sort of durable plastic or something similar. Kevlar fibers tend to snap when stretched meaning as you're scraping down the highway the kevlar will break itself up very quickly. Usually it's mixed with nylon or other substances to help it keep itself together.

A true armored jacket like jonnythan said is very thick and works to stop the bullet from penetrating by collapsing sections.

[JC Viper]

Motorcycle gear already sport a similar fiber called aramid in their gear, especially the pants.

Here is more info on the benefits of kevlar: http://en.wikipedia.org/wiki/Kevlar

Kevlar can be expensive so I doubt an article of clothing will contain more than a few patches.

Get a good leather or textile jacket for abrasion resistance and since the chest is another area that can be severely damaged in an accident a good chest protector (like the Icon version) is also a good investment for protection.

[ninja79]

As everyone says, neither leather nor kevlar protect from impact. You need armour and padding for that. However, they do a pretty good job at protecting from abrasion.

The only company I know of that makes "kevlar" gear is motoport. (I wonder why...). They actually use two completely different materials which they call "kevlar". The first one is "Air Mesh Kevlar". That truly is a mesh (similar to polyester mesh like Joe Rocket Phoenix). However, it is very stiff and bulky. The other fabric is "Stretch Kevlar Blend". That is not a mesh, but it is fairly breathable (similar to thick denim). It is very soft and stretchy. It looks and feels very similar to keprotec, which is used in stretch panels on leather jackets and pants (e.g. see here or here). I own version 1.0 of that jacket, and the stretch panels on the sleeves look *very * similar to the stuff my pants are made of.

According to the company propaganda "Air Mesh Kevlar" actually has less abrasion resistance than leather or 620 denier cordura. However, "Stretch Kevlar Blend" supposedly has greater abrasion resistance than leather.

This is consistent with the claims I heard about kevlar. It has an incredible tensile strength (i.e. if you take a strand of kevlar and pull it apart, the force required to break it is very high). This is what allows it to stop a bullet. However, it has a rather mediocre abrasion resistance (i.e. if you rub a patch of kevlar with sandpaper, it will not last as long as leather).

The stuff that is typically used for motorcycle gear is actually keprotec, which is a blend of kevlar, cordura, and lycra. Motoport people don't say this, but I'm almost positive that's what their "Stretch Kevlar Blend" is.

Anyway, last year I actually went down there to check out their wares. They have a small office/factory/warehouse at a plaza in Carlsbad, about 2 hours south of Los Angeles. I ended up ordering their "stretch kevlar" overpants, primarily because I was not able to find any other overpants that are both strong (cordura/leather) and breathable. The choices from other manufacturers were either polyester mesh (kinda weak...) or "waterproof" cordura/nylon (too hot/non-breathable).

About 14 weeks and over $300 later, I got them. Expensive, but pretty well maid and comfortable. They also have long knee/shin armour and hip armour. My only complaint is that the knee armour is about an inch too low. However, I can shift it up when I get on the bike, and at some point I'll improvise something to support it from the bottom. Also, I need to saw the zipper to attach it to my jacket, cause every manufacturer has their own "standard".

However, I decided not to get the full suit from motoport and instead I'm sticking with my leather jacket. It is quite breathable and comfortable due to perforated panels, has very good armour coverage, and you can't beat the price.

[Shiv]

Well I knew that impact is the hard part to protect against, which is why I was wondering if kevlar would give you any advantage in that regard but it seems not.

[JC Viper]

Well I knew that impact is the hard part to protect against, which is why I was wondering if kevlar would give you any advantage in that regard but it seems not.

Bulletproof vests have kevlar in it and some other fabrics woven together to distribute the force of a bullet to lessen the impact. I'm trying to recall what I heard on the History channel.

[ninja79]

kevlar is just fabric. The only thing special about it is tensile strength. A bullet will not penetrate the kevlar fabric, but the impact will still break your bones. That's why you need hard parts to distribute shock.