[adouglas]

So the Kevlar panels are stitched to an outer shell that is nothing but a pair of ordinary jeans. If the outer shell falls apart or abrades away where the kevlar is attached, what happens?

Say the Kevlar is stitched really, really well to your cotton jeans. We know that cotton sucks for abrasion. The seam itself can be well designed and stitched with the very best kevlar thread, but if the material on the other side of that seam fails, then by definition the whole thing fails.

From a common sense standpoint, it seems to me that all the critical aspects of a garment... the seams, the thread, the material on both sides of the seam... must be crashworthy to call the whole thing crashworthy. Chain is only as strong as its weakest link, and all that.

If that is true, then a panel of kevlar sewn into a garment that itself cannot survive a crash is therefore not going to magically create something that will survive.

This is one reason why I'm skeptical about riding jeans. They may be fine for an off at low speed, but going down at any respectable velocity? Really, really not sure about that.

IMHO the idea of a layered garment made of various kinds of sacrificial fabric -- which is what riding jeans are -- makes sense in principle.

But for it to really work, I believe there has to be a solid layer somewhere in there that will hold together and resist abrasion. Such a product does exist... kevlar long-johns. But once you go there, you're getting right back into the territory that makes you want to buy riding jeans in the first place: comfort, or lack thereof.

Full disclosure: I've only gone full-leather in the past few years. Before that I did a whole 2600 mile tour using Kevlar long underwear and some Fieldsheer overpants (which I still use when the weather is really foul or cold).

Didn't go down, of course, so no first-hand knowledge. But in between the stout overpants and the solid kevlar layer beneath, I felt well protected. Downsides: Not exactly street clothes, plus the overpants were loose enough that armor could shift. Upsides: Weather resistance. Somewhat lower cost than leathers.