Denier For Motorcycle Crash Protection: 600D to 1000D

Question:
I'm in the market for a new textile riding jacket (leather is too expensive for my college-student budget), and I've noticed that fabric is often referred to with a number followed by the letter "D," as in 600D or 800D. What's that code for, and why does it matter? -Alan Forsythe/ Princeton, NJ

Answer:
Let's get technical for a minute. Denier, often abbreviated as just "D" or "d," is the weight of 9,000 meters of a given fiber. A single strand of silk is about 1D because 9,000 meters of it weighs 1 gram. That same length of whatever fiber is used in 600D fabric weighs 600 grams.

In practical, non-nerdy terms, a higher Denier indicates a thicker, heavier, and more tear- and abrasion-resistant fabric. It’s not really as simple as that, though. The fiber itself makes a big difference. Cordura nylon, for example, is renowned as a tough, durable fabric. But it’s also expensive, so some clothing manufacturers opt for a cheaper, no-name polyester material to keep the price down.

A higher Denier usually results in a stiffer, heavier garment, giving it less showroom appeal to some potential buyers. Remember, though: Dress for the fall, not for the ride. Besides, high-Denier fabrics often lose some of the stiffness after they’ve been worn a while.

Armor is a must in riding clothes. The current standard is CE 1621, which should be stamped on or molded into each pad. Adjustment straps on the sleeves to snug up the forearm fit help prevent armor from rotating away from your elbow in a crash or a slide. Back protectors are considered options by many jacket manufacturers, but you should think of them as mandatory.

Got a question you want answered? Send it to mcmail@bonniercorp.com