Dangerboy Decimal Chromoly Cog – HG Freehub Compatible 15.3 to 18.8

*New heat-treated cogs are now black. Updated product photos coming soon.

Dangerboy Decimal Chromoly Cog – HG Freehub Compatible

Specially developed for BMX racing, the Dangerboy Decimal Series Cogs are engineered from heat-treated Chromoly steel for superior durability, power transfer, and resistance to wear.

Each cog is CNC-machined to precise decimal tooth sizes, allowing riders to fine-tune gear ratios for optimal cadence and track conditions. The 5 mm wide inner base ensures a solid, stable interface with HG-style freehub bodies, improving torque distribution and drivetrain efficiency.

Specifications:

• Material: Heat-Treated Chromoly Steel

• Process: CNC-Machined

• Finish: Raw Stainless Steel with Laser-Etched DB Graphics

• Sizes: 15.3T, 15.8T, 16.3T, 16.8T, 17.3T, 17.8T, 18.3T, 18.8T

• Driver Compatibility: HG Freehub Body

• Chain Compatibility: Full Link Chain

• Base Width: 5 mm

Highlights:

• Precision decimal sizing for fine gear ratio adjustment

• CNC-machined for flawless fit and chain alignment

• Increased stiffness and long-lasting durability

• Ideal for elite BMX racers and drivetrain tuning

• Raw finish with signature laser-etched DB graphics

The way to calculate a decimal cog is to interpolate between two whole cog sizes.

For example, with a 44 / 16 gear ratio, if you’re considering a 16.3 cog, you:

• Take the rollout difference between a 16T and 17T cog

• Then subtract 30% of that difference from the 16T rollout (since 16.3 is 30% of the way to 17)

This gives you an accurate estimate of the effective rollout for a 16.3 cog.