WHAT IS IT? Anatomically profiled for all forms of off-road riding, Alpinestars’ Bionic Pro Plasma knee protectors are made to be lightweight, breathable and comfortable, offering superb protection for your knees. 

WHAT’S IT COST? $144.95. 

CONTACT? www.alpinestars.com or your local dealer. 

WHAT STANDS OUT? Here’s a list of things that stand out with the Alpinestars Bionic Pro Plasma knee protectors.  

(1) Concept. Knee injuries have long been a problem in motocross, and, unfortunately, no knee pad or knee brace can guarantee your safety. Over the years, the medical team (once called Asterisk Mobile Medics and now called the Alpinestars Mobile Medics) has documented all of the major injuries and kept receipts on the protective gear each injured rider was wearing. Their studies found knee injuries at the pro level to be a 50/50 split between riders with knee braces and riders with knee pads. Riders who had previously suffered knee injuries usually found solace in bracing their knees, but the studies show injuries can happen in braces as well. 

Kevin Windham, Justin Hill, Michael Mosiman and Justin Barcia are a few notable pros who wear (or wore) knee pads. The Alpinestars Bionic Pro Plasma knee guards are on the expensive side, but the engineering that went into this design is not snake oil. These pads are protective, breathable and snug-fitting. 

(2) Construction. At the core of the protector is Alpinestars’ Nucleon Plasma material (similar to D30 and other impact-absorbing rubber compounds). It’s pliable in all directions but still able to dissipate impacts. This Nucleon Plasma material is at the core of multiple Alpinestars protective products with the Bionic Plasma name, including Alpinestars’ elbow pads and chest protectors. 

The exterior portion of the guards is made out of two, independent, thermoplastic shells strategically positioned over the patella to help your knees slide across the ground in a crash and absorb impacts. 

(3) Fit & function. Making a protective knee pad is the easy part; keeping it from sliding down the rider’s leg during a moto or while walking through the pits is the hard part. Legs come in all sorts of shapes and sizes, but knee pads usually only come in two sizes—small/medium and large/extra large. The Alpinestars Bionic knee guards have two straps—one above the calf and one at the top above the knee. Thankfully, they offer ample adjustment; usually, pads can’t get tight enough. To put them on, slip your foot through the sleeve and then secure the straps. The elastic top strap is wider than most knee pads to improve comfort and create a secure closure. 

The bottom strap can be tightened nice and snug, which is important for keeping the pads in place during a long moto. The top strap is considerably looser, with excess material in the L/XL size for our tester weighing 175 pounds. If you’re 185 or above, we recommend the L/XL size, but if you’re 175 or below, you might need the S/M size. Even with the top strap on the looser side, the Bionic knee pads still held their position well. 

MXA also tested the Bionic Plus knee protectors, which are much cheaper with less material and less protection. They were lightweight and breathable, but they didn’t offer nearly the same protection. And, because the straps weren’t as sturdy, the Velcro came loose more easily, allowing the pads to slide down our test riders’ legs quickly.

Compared to knee braces, these pads are cheaper, and they fit better, which means they are less likely to slide down your leg. Knee pads are also less restrictive, which is important when making quick movements with your feet and legs. 

WHAT’S THE SQUAWK? The top strap was too loose for our testers. We wanted to try a size down, but they were out of stock during our test. 

MXA RATING: We’d recommend Alpinestars’ Bionic Pro Plasma knee pads for anyone looking for a high-quality knee pad. They aren’t cheap, but we don’t want cheap when it comes to protection and comfort.