We’ve been making a big fuss over thin, flexible D3O, but it’s not the only choice if you’re looking for slimmer motorcycle armor. This Alpinestars Bio Armor may not be bright orange or come with science we hardly understand, but it is safe. 100 percent safer than traditional Alpinestars foam armor, for example, while only measuring about 1cm in thickness. It’s this that we’re installing in our safest tier of jacket as part of our as-yet-unnamed project to make actually good-looking, yet still safe motorcycle gear.

Check out this picture of a size large Bio Armor elbow guard (on the right) next to size small Alpinestars foam elbow guard (left). That foam protector on the left exceeds CE certification EN 1621-1 and is already only about 1.5cm thick and very flexible.

Alpinestars Bio Armor explained

This chart compares that Bio Armor elbow guard to that foam elbow guard in the EN 1621 test. The foam armor, in white, exceeds the standard, but the thinner, more flexible Bio Armor averages 100 percent less force transmitted to the rider from the impact test. That’s huge. Bio Armor will be replacing the foam across the Alpinestars jacket range.

A, B and C are different locations being tested on the armor. A is above the elbow, B on the point and C is below. In the EN 1621 impact test, which is the standard all CE-approved joint armor is tested to, an 11lbs weight with a 1.5 x 1.0-inch striking face is propelled into the armor with 37lb/ft (50j) of energy. The average force transmitted through the armor must average 39kN or less.

That probably doesn’t mean much to you, but you likely have an idea of what it feels like to hit something with CE-certified foam armor. Cut that transmitted force in half and you have Bio Armor.

The company isn’t revealing the exact compound used in creating Bio Armor, but calls it a “specially formulated closed cell foam.” It feels like rubber and is malleable and flexible in a way that belies its contoured shape.

The EU is in the process of drafting a new certification level that will include tests in very hot and humid conditions of the kind that can soften traditional foam. Alpinestars claims Bio Armor is already tested to work in a wide variety of climactic conditions.

Comparing the safety of Bio Armor to D3O is frustratingly difficult as neither company publishes exact force transmission levels and we’re not equipped with a safety lab in which we could test them ourselves. Both products are similar in shape and size, with neither taking, at this early stage in the project, an apparent lead in wearability or comfort.

Where Bio Armor does appear to have a massive edge is in availability and cost. Kits which include a pair of elbow and shoulder protectors are widely available for around $40 while CE Level-1 Bio Armor back protector inserts are only $30.

Sewing starts tonight. Seriously, please help us come up with a name for this project.

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