Troy Lee Designs D4 Composite BMX Full-Face Helmet LG, MD

LG size available upon request. We will exchange the headliner and cheek pads to XL sizing at no additional cost. Please note that MD and LG share the same shell size; the difference is in the interior padding only. Please email sales@bikesupplies.ca or include a note in your order requesting LG sizing.

Troy Lee Designs D4 Carbon & Composite Full-Face Helmet – BMX Race Proven

The Troy Lee Designs D4 Carbon and D4 Composite helmets set the standard for high-performance BMX full-face helmets. Designed for elite BMX racing, BMX freestyle, and downhill riding, the D4 is trusted by top riders worldwide for its lightweight construction, exceptional ventilation, and race-ready fit.

Both the D4 Carbon and D4 Composite share the same advanced helmet platform, delivering pro-level protection with reduced weight and increased comfort compared to entry-level full-face helmets. The carbon version offers maximum weight savings, while the composite model delivers an ideal balance of strength, performance, and value — making both excellent choices for competitive BMX riders.

At the core of the D4 is the Mips® C2 rotational impact protection system, engineered to reduce rotational forces during angled impacts commonly seen in BMX crashes. A large front air intake and optimized ventilation channels move air efficiently through the helmet, helping riders stay cool during motos, mains, and extended training sessions.

An anatomically refined shell shape combined with 3D-contoured cheek pads provides a secure, locked-in fit without pressure points. Emergency quick-release cheek pads allow for safe helmet removal by first responders. The removable, washable comfort liner uses Coolmax® and Dri-Lex® materials to manage sweat and maintain comfort in high-intensity riding conditions.

Whether you’re racing BMX, riding indoor tracks, or lining up for nationals, the Troy Lee Designs D4 Carbon and Composite full-face helmets deliver proven safety, performance, and premium build quality.

This helmet is designed and intended exclusively for bicycling activities, including BMX racing, BMX freestyle, downhill MTB, and off-road cycling.

Key Features:

• D4 full-face helmet platform used by elite BMX and downhill riders

• Available in Carbon and Composite shell constructions

• Mips® C2 rotational impact brain protection system

• Three shell sizes for accurate fit across youth and adult riders

• Anatomical 3D contoured cheek pads with emergency release system

• Removable, washable comfort liner with Coolmax® and Dri-Lex® moisture-wicking materials

• Lightweight titanium D-ring retention system

Specifications:

• Certifications: CPSC 1203*, CE EN1078*, ASTM F1952 (Downhill), ASTM F2032 (BMX)

• Weight: varies by shell construction and size

*Certification standards vary by region

D4 Carbon vs D4 Composite – Which One Is Right for You?

D4 Carbon

Best for riders who want the lightest possible full-face helmet for BMX racing and high-intensity riding. The carbon shell reduces overall weight while maintaining maximum strength, making it ideal for gate starts, repeated sprints, and long race days. If weight savings and top-tier performance are the priority, D4 Carbon is the premium choice.

D4 Composite

Designed for riders who want elite-level protection and fit at a slightly lower cost. The composite shell offers excellent impact performance and durability while sharing the same ventilation, Mips® C2 protection, and anatomical fit as the Carbon version. D4 Composite is an outstanding option for competitive BMX racers looking for performance and value.

Quick comparison:

Shell material

• Carbon: carbon fiber

• Composite: advanced composite construction

Weight

• Carbon: lightest option

• Composite: slightly heavier, still race-ready

Performance level

• Carbon: pro-level, weight-focused

• Composite: elite performance with added value

Best use

• Carbon: BMX racing, national-level competition, riders prioritizing weight

• Composite: BMX racing, training, nationals, riders balancing cost and performance

Shared features (both models):

• D4 full-face helmet platform

• Mips® C2 rotational impact protection

• Identical ventilation and airflow system

• Same anatomical fit and shell shaping

• Emergency-release cheek pads

• BMX and downhill safety certifications