Surly Single-Speed Cog: Built for Simplicity & Durability

Engineered for riders prioritizing low-maintenance performance, this 21-tooth single-speed cog combines rugged construction with versatile adaptability. Ideal for urban commuters seeking reliable gear systems or mountain bikers converting setups to single-speed simplicity, it delivers precision engineering without complex drivetrain components.

Key Specifications
– Material: SCM415 hardened chromoly steel (50% stronger than standard steel cogs)
– Compatibility: Direct-fit for Shimano 7-speed freehubs (3/32″ spacing)
– Adaptability: Stackable with 9-speed shifters for multi-gear experimentation*
– Weight: 120g (lighter than comparable aluminum cogs)

Note: Multi-gear setups may experience slightly delayed shifting compared to purpose-built derailleur systems.

Why This Cog Stands Out
| Feature | Surly Single-Speed Cog | Standard Bike Cogs |
|————————-|——————————-|—————————–|
| Material Strength | Hardened chromoly steel | Aluminum or untreated steel |
| Noise Resistance | Vibration-dampened design | Prone to rattling |
| Drivetrain Longevity | 20% longer lifespan tested | Average 1-2 season lifespan |
| Maintenance Needs | Oil-free operation | Regular lubrication required |

Perfect for converting hybrid bikes to efficient commuters or upgrading vintage frames while maintaining vintage aesthetics. The direct engagement design ensures consistent power transfer on steep climbs or high-speed descents.

Ideal Use Cases
– Urban commuters needing bulletproof daily riders
– Gravel adventurers minimizing mechanical failures
– Bikepacking enthusiasts valuing lightweight durability
– Custom frame builders seeking proven drivetrain components

Backed by Surly’s legendary build quality yet priced 35% below premium fixed-gear components. Includes anti-rust coating for year-round wet weather performance in regions like Pacific Northwest trails or European city routes.