By The Seat of Your Motorcycle Pants …by Bernard H. Wood

Posted: February 14, 2016 in Motorcycle advocacy, motorcycle safety
Tags: , , , , , , , , ,

Kevlar Motorcycle Riding Pants

Ensuring that the shredded trail of hide, cheese-grated across the tarmac isn’t yours. It’s much better that it’s the outer layers of a long-dead bovine or strands of some semi-synthetic concoction that have never experienced a previous, grass-munching existence.

Historically, the go-to when it came to protective gear was, of course, leather. Incorporated into protective armour for centuries, it became an obvious, affordable, and robust choice.

Then technology leaped forward, and we can now choose from various combinations of modern protective materials, including ballistic nylon, Taslon, Gore-Tex, Cordura in various hybrids and percentages. This means there are now hundreds of options that allow you to get the best in terms of both price and performance.

The ubiquitous Kevlar Jeans are a product of modern textile technology, offering a solution that provides both stylish comfort and rider protection. When the word “Kevlar” is dropped into a conversation, part of us feels instantly reassured, but the reality is a little more convoluted than it may first appear.

For a start, “Kevlar” is fast becoming a catch-all for certain protective materials. Along with “Hoover” and “Biro”, it’s a brand name used to rope together a set of ‘things’ for convenience. “Kevlar” as a name and a material is owned by DuPont.

It’s a high strength synthetic fibre composed of poly-paraphenylene terephthalamide that was invented by chemist extraordinaire Stephanie Kwolek at the company labs in 1965. If it’s not Kevlar by DuPont, then it’s not Kevlar, fact.

DuPont even take steps to chase down those who falsely claim that their products contain Kevlar when they patently do not. Perhaps the price tag on a surprisingly cheap pair of “Kevlar Jeans” is just too good to be true?

This does not mean that the jeans in your wardrobe – or on your legs – aren’t reinforced or protective to a greater or lesser degree, “good” or at least good enough. They (probably) contain fibres derived from the “aramid” or  “para-aramid” families of super-tough synthetic materials fashioned into internal linings.

They may even contain Kevlar, proper, or other materials from the same family. Cheaper jeans may incorporate these wonder materials in “part lined” form (as opposed to “fully lined”), or only as patches to cover so-called ‘crucial areas’ – but as far as we’re concerned, keeping your whole body protected is crucial

Perhaps the more astute would look for a CE approval rating of level 1 or 2, but there is a crucial difference between jeans that are CE rated and jeans that contain only patches of CE rated protection. Take care.

Of course, the material properties are only part of the issue. The quality of assembly is crucial when it comes to both traditional leathers and the modern alternatives. There’s more flexibility with a synthetic material that can be spun to any length or width and sold by the meter, but with current technology, it still comes down to stitching material panels together and trusting that they will hold. Back to the principles of old school craftsmanship.

Leather presents a particular challenge in the sphere of protective clothing due to its non-uniform nature. It’s a relatively expensive material subject to variations in unit size and quality and whose inherent tanning process can imbue the treated hide with substances that may even eroded the integrity of the stitching itself – unless the thread is suitably resistant.

Even with good quality leather, the very nature of stitched panels introduces problems of material integrity. Seams are ultimately points of weakness. More panels equate to more seams which in turn equate to more “weak links”. Theoretically speaking, manufacturers should choose the largest single area of leather and assemble garments with the fewest number of panels/seams.

Fewer panels naturally require larger areas of whole leather and therefore larger, high quality hides, returning us back to the issue of expense once more. So it’s a matter of compromise, or perhaps more charitably, “balance”.

The type of stitching – whatever the material – is also critical. A line of external single stitching? Not so great, especially if it comes into contact with an abrasive road surface at speed. Then your expensive jeans (or jacket) may disassemble into several (admittedly high quality) material panels, leaving your own hide to take the grind.

External double-stitching across panels, coupled with additional internal stitching is surely a better idea. Even if the tarmac chews through two outer two lines, then the inner stitching remains as an extra backup. Further protection is also offered by additional padding/reinforcement and by the addition of armoured sections – to protect knees, for instance.

So how do you verify the efficacy of the garment, pre-market? Well, with the help of bodies such as the Shoe and Allied Trade Research Association, or SATRA for short. They make it their business to poke, prod, abrade and generally abuse items and materials to ascertain their durability, measured against European and international standards of quality.

Take the Motorcycle Abrasion Tester for instance. It “allows an assessment of the initial impact and abrasion that may occur when a motorcyclist is involved in an accident and thrown from their machine”, according to the official text.

The device is set inside a protective transparent box and features a cantilever head on which material samples (cut-out sections of jeans for instance) may be mounted. The head then impacts upon a rotating, abrasive belt and maintains pressure, whilst an internal clock records the time taken for the abrasion to penetrate the material. The grindings from the process are automatically brushed from the belt and vacuumed away whilst the simulated rider goes for a scrape down a synthetic roadway.

Simple yet ingenious, and a more controllable than dragging a pair of jeans around a racetrack, though that too has been done – even with someone wearing them at the time. Hardcore.


P.S.  Mr. Woods guest blog post is curtesy of Hideout Leathers in the UK purveyors of racing, touring, police and bespoke motorcycling gear. Please take a few minutes to check their site, you might be quite surprised!     Warren






  1. Experimental Ghost says:

    Excellent post Warren. Thanks for posting it up

  2. Lots of wonderful information here! I wonder if anyone has created a top 10 list of the best/most resistant kevlar jeans? That would be so helpful.

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