Hand & Wrist Biomechanics • Street & Track Racing|CE EN 13594:2015 Level 2 KP Standard
The Biomechanics of Hand Defense: Knox SPS Sliders, Kangaroo Tensile Science & CE Level 2 KP
When a rider falls, human instinct commands the hands to extend forward to break the impact (Fall on Outstretched Hand, or FOOSH). On asphalt at 60 mph, standard leather grips the road with massive frictional drag (μ ~ 0.72), converting the rider's momentum into an axial bending moment that snaps the carpal scaphoid bone. Discover the material chemistry, low-friction slider mechanics, and tear-resistant fiber physics that protect the human hand.
Palm Slider Friction
μ < 0.20
Converts high-torque road grab into low-friction slide
Kangaroo Tensile Strength
180 - 210 MPa
Twice the tensile density of cowhide at 0.8mm thickness
CE Level 2 Abrasion
> 8.0 Seconds
Cambridge abrasive belt duration without burn-through
Knuckle Transmitted Force
< 5.0 kN
CE EN 13594 Level 2 KP mandatory impact limit under 5J
Interactive Mechanical Dissection
The 5 Critical Protective Components of a Racing Glove
Anatomical Hand Map • Zone 1 ActiveSpecification: μ < 0.20 on dry asphalt
ZONE 1Carpal Scaphoid Fracture & Grab-Twist Prevention
Positions dual pucks over the thenar and hypothenar eminences. During a Fall on Outstretched Hand (FOOSH), the low-friction pucks slide across the road, eliminating the forward grab-and-pitch moment that snaps the scaphoid.
EN 13594 Level 2 palm impact and abrasion resistance.
Friction / Ratingμ < 0.20 on dry asphalt
Biomechanical Physics Simulator
Scaphoid Fracture Mechanics: Friction Coefficient vs. Axial Bending Moment
Calculate the axial compressive force exerted on the carpal scaphoid bone during a Fall On Outstretched Hand (FOOSH). See how replacing high-friction leather (μ ~ 0.72) with low-friction Knox SPS sliders (μ ~ 0.18) drops transmitted wrist force below the 1,200 N fracture threshold.
Kangaroo leather has an exceptionally tight, cross-linked collagen fiber structure with zero sweat glands in the lower dermis. This allows a 0.8mm kangaroo hide to match or exceed the tensile and abrasion strength of 1.3mm premium bovine leather while reducing bulk by 38%.
Nominal Thickness
0.85 mm
Tear Resistance
45 N (EN 388 Test)
Thermal Stability
140°C shrink threshold
Micro-Structure Matrix
Continuous multidirectional collagen bundles without weak inter-layer fat deposits.
Regulatory Standards Matrix
CE EN 13594:2015 Benchmark Requirements (Level 1 vs. Level 2 KP)
Test Parameter
Testing Apparatus
Level 1 Threshold
Level 2 KP Threshold
Clinical Relevance
Impact Abrasion Resistance
Cambridge Abrasive Belt
>= 4.0 seconds
>= 8.0 seconds
Prevents burn-through to bare skin during 70+ mph slide
Seam Burst Strength
Tensile Tensometer
>= 6.0 N/mm
>= 10.0 N/mm
Guarantees seams do not split under torsional road friction
Tear Strength
Trouser Tear Rig
>= 25 N
>= 35 N
Prevents snagging and tearing on curbs or footpegs
Knuckle Impact Protection
5J Drop Hammer Strike
Optional (<= 9.0 kN)
MANDATORY (<= 5.0 kN)
Attenuates direct blunt impact away from metacarpal heads
Wrist Restraint Retention
50 N Pull-Off Rig
>= 25 N pull
>= 50 N pull (Dual lock)
Guarantees glove cannot be stripped off during tumbling
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