RNC Legend Ultra-Lite Top Load Stem (40mm, 48mm & 52mm) *Ti Bolts Stock*

The RNC BMX Legend Top Load Stem represents the next evolution in lightweight, high-performance BMX stem technology.

Precision CNC machined from premium 7050-T7451 aerospace-grade aluminum, the Legend was engineered to deliver an exceptional combination of strength, stiffness, fracture toughness, and minimal weight.

Through advanced CAD design and extensive 3D CNC machining, unnecessary material has been eliminated while maintaining strength in critical areas. The result is an incredibly lightweight top load stem weighing just Weight: 40mm - 145 grams / 5.1oz 48mm - 149 grams / 5.3oz 

PREMIUM 7050-T7451 AEROSPACE ALUMINUM:

Unlike conventional BMX stems manufactured from 6061 or 7075 aluminum, the Legend is machined from 7050-T7451, a premium aerospace alloy selected for its exceptional combination of mechanical properties.

With an ultimate tensile strength of approximately 76,000 PSI, 7050-T7451 delivers an outstanding combination of high strength and fracture toughness.

Why 7050-T7451?

Superior Strength to 6061 Aluminum

7050-T7451 offers significantly higher tensile and yield strength than conventional 6061-T6/T651 aluminum. This allows us to engineer a lightweight stem while maintaining excellent resistance to permanent deformation under demanding riding loads.

Exceptional Fracture Toughness Compared to 7075

While 7075-T6/T651 aluminum is known for its high tensile strength, 7050-T7451 offers a major advantage in fracture toughness.

Fracture toughness measures a material's ability to resist the growth of an existing crack. The higher fracture toughness of 7050-T7451 helps improve resistance to crack propagation under extreme loading conditions.

This is especially valuable in highly stressed components such as BMX stems, which experience repeated impacts, vibration, and heavy loading.

Engineered for Strength, Not Just Weight

Rather than simply choosing the aluminum alloy with the highest advertised tensile strength, we selected 7050-T7451 for its balance of strength, fracture toughness, and durability-related properties.

The result is a premium material ideally suited to our aggressively weight-optimized top load stem design.

ADVANCED 3D CNC MACHINING:

The Legend Top Load Stem is extensively 3D CNC machined to remove unnecessary material while preserving critical structural areas.

Every contour and pocket has been carefully engineered to maximize strength-to-weight efficiency.

At just 149 grams, the Legend delivers an exceptionally lightweight top load design without relying on conventional 6061 aluminum.

HEAT-TREATED TITANIUM BOLTS:

The Legend includes premium CNC-machined USA-produced medical implant-grade 6Al-4V titanium bolts.

These bolts are heat treated and aged to approximately 170,000 PSI tensile strength, providing exceptional strength while minimizing weight.

SPECS:

• Model: RNC BMX Legend Top Load Stem
• Material: Aerospace-grade 7050-T7451 aluminum
• Aluminum Tensile Strength: Approximately 76,000 PSI
• Manufacturing: Precision 3D CNC machined
• Bolts: USA-produced implant-grade 6Al-4V titanium
• Bolt Tensile Strength: Approximately 170,000 PSI
• Reach: 40mm, 48mm & 52mm
• Rise: 20.5mm
• Stack Height: 26mm
• Weight: 40mm - 145 grams / 5.oz  48mm - 149 grams / 5.26 oz
• Design: Advanced weight-optimized top load construction
• Origin: 100% MADE IN THE USA

AVAILABLE COLORS:

Silver • Black • Red • Blue • Purple • Green • Pink • Orange • Gold • Turquoise