Shimano DXR2 Crankset

Overview

The Shimano DXR2 (MX71) is a lightweight race crankset engineered for BMX and 4-cross competition. Featuring hollow 6061-T6 aluminum arms with a pressed 24mm chromoly spindle and redesigned 4-bolt spider, this crankset delivers exceptional stiffness-to-weight ratio and includes an external Euro bottom bracket for extended bearing life and improved rigidity.

Key Features

• Hollow 6061-T6 Aluminum Arms — Lightweight yet incredibly stiff construction resists flex during hard pedaling and aggressive tricks; aerospace-grade aluminum provides strength without excess weight
• Steel Pedal Boss Inserts — Hardened steel inserts at pedal attachment points prevent stripping and wear; ensure reliable pedal security through repeated use
• Redesigned 4-Bolt Spider — Modern gear mounting system reduces weight compared to earlier designs; 104mm BCD (bolt circle diameter) maintains standard chainring compatibility
• Integrated Heat-Treated Chromoly 24mm Spindle — Pressed to drive-side arm for maximum strength; hollow chromoly construction balances durability with minimal weight
• Included External Euro Bottom Bracket — Seamless integration with included BB; allows use of oversized bearings for increased rigidity and extended bearing life
• Spacer Included — Installation spacer provided for proper frame compatibility
• Race-Focused Engineering — Evolved from popular Hollowtech II platform; designed for BMX racing and 4-cross performance demands

Technical Specifications

• Crank arm material: 6061-T6 aluminum alloy
• Construction: 2-piece hollow design
• Spindle diameter: 24mm
• Spindle material: Heat-treated chromoly steel (integrated, pressed)
• Spider mounting: 4-bolt
• BCD (bolt circle diameter): 104mm
• Pedal boss: Steel inserts
• Bottom bracket: Included Shimano external Euro BB
• Weight (with BB and spacer): 765g
• Weight (without BB, spacer, or screws): 729g
• Thread type: 1.37-inch × 24 TPI (English)

Compatibility & Ideal Use Cases

Compatible with frames featuring 68mm or 73mm × 1.37-inch English-threaded bottom bracket shells. Works with all 104mm BCD chainrings and standard 9/16" pedals. The included external Euro bottom bracket ensures seamless compatibility and optimal performance. Ideal for BMX racers and 4-cross competitors seeking a lightweight, stiff crankset engineered specifically for racing demands. The hollow aluminum construction and chromoly spindle deliver responsive acceleration and reliable power transfer under high loads. Well-suited for riders prioritizing performance and reduced rotating mass over budget pricing. Essential upgrade from entry-level cranksets for competitive racing applications.