Box Four Crankset

Box Four Crankset

Product Overview

The Box Four is a cold-forged BMX crankset featuring a 24mm chromoly spindle and 104mm BCD 4-bolt spider. Available in 160mm, 165mm, and 170mm lengths, it includes an external BSA bottom bracket and dual pinch bolts for secure clamping.

Key Features

• Cold Forged Construction – Manufacturing process compresses aluminum to increase density and strength; produces durable crank arms without material waste
• 4-Bolt 104mm BCD Spider – Standard BMX chainring pattern compatible with Box and other brands offering 104mm 4-bolt chainrings
• 24mm Chromoly Spindle – High-strength steel spindle resists bending and provides durability for racing and freestyle applications
• 6061-T6 Aluminum Crank Arms – Lightweight yet rigid construction maintains strength while minimizing rotational weight
• External BSA Bottom Bracket Included – Pre-selected BB eliminates guesswork; compatible with standard external BB frames
• Dual Pinch Bolts – Two clamping bolts distribute force evenly across spindle, preventing slippage and damage
• Laser-Etched Graphics – Durable branding without added weight
• Multiple Crank Lengths – Available in 160mm, 165mm, and 170mm to accommodate different rider heights and preferences
• Matte Black Finish – Clean aesthetic compatible with most BMX builds

Technical Specifications

• Crank arm material: Cold-forged 6061-T6 aluminum
• Spindle material: 24mm chromoly steel
• Spindle diameter: 24mm
• Bottom bracket: External BSA (included)
• Chainring pattern: 4-bolt, 104mm BCD
• Crank length options: 160mm, 165mm, 170mm
• Clamping system: Dual pinch bolts
• Finish: Matte black with laser-etched graphics
• Weight: Lightweight cold-forged construction

Compatibility & Ideal Use Cases

• External BSA bottom brackets – Includes compatible BB; works with standard external BSA BB frames
• 4-bolt 104mm BCD chainrings – Compatible with Box and other brands offering 104mm 4-bolt chainrings (chainring sold separately)
• BMX racing and freestyle – Suitable for all riding disciplines
• Crank length selection – Choose based on rider height and preference; 160mm–165mm standard for most adult riders, 170mm for taller riders
• Beginner to advanced riders – Versatile option for builds at any skill level

Build Requirements & Compatibility

• Chainring – Sold separately; select 104mm BCD 4-bolt chainring to match your gearing needs
• Bottom bracket – Included external BSA BB; verify frame compatibility before ordering
• Pedals – Not included; purchase separately with washers for secure installation
• Spoke tension – Use calibrated spoke tension meter for proper wheel building

Important Notes

• • Bottom bracket included; no additional BB purchase required
  • Chainring sold separately; choose based on desired tooth count and riding style
  • Ships direct from manufacturer in USA; may ship separately from other orders
  • Cold-forged construction provides proven durability and lightweight performance
  • Dual pinch bolts require proper installation to prevent spindle damage; tighten evenly