Dangerboy Decimal Chromoly BMX Race Cogs – Onyx / Oversized Freehub Compatible – 15.3T–18.8T

Specifically engineered for BMX racing, Dangerboy Decimal Chromoly Cogs offer precise gearing adjustments for competitive riders looking to fine-tune their performance.

CNC-machined from heat-treated chromoly steel, these cogs deliver exceptional strength, durability, and consistent chain engagement under the explosive power demands of BMX racing.

Unlike traditional whole-tooth cogs, decimal cogs allow riders to make smaller gearing adjustments without changing their front chainring. This provides greater flexibility when optimizing gearing for different tracks, conditions, and rider preferences.

Designed for Onyx and compatible oversized freehub bodies, each cog features a 5mm-wide base for a secure interface, improved load distribution, and reduced wear on the freehub body.

Features & Specifications

• Material: Heat-Treated Chromoly Steel
• Construction: Precision CNC-Machined
• Finish: Raw Steel with Laser-Etched Dangerboy Graphics
• Available Sizes: 15.3T, 15.8T, 16.3T, 16.8T, 17.3T, 17.8T, 18.3T, 18.8T
• Freehub Compatibility: Onyx / Compatible Oversized Freehub Bodies
• Chain Compatibility: Full-Link BMX Chains
• Base Width: 5mm
• Application: BMX Racing

Why Choose Decimal Gearing?

Decimal cogs provide intermediate gearing options between traditional whole-tooth sizes, allowing riders to fine-tune their rollout without changing chainrings.

For example, a 16.3T decimal cog provides an effective gearing ratio between a traditional 16T and 17T cog, giving riders a smaller adjustment than switching between whole-tooth sizes.

How to Calculate Decimal Cog Rollout

To estimate the rollout of a decimal cog, interpolate between the rollout values of the two closest whole-tooth sizes.

For example, when using a 44T chainring with a 16.3T cog:

1. Calculate the rollout with a 16T rear cog.
2. Calculate the rollout with a 17T rear cog.
3. Determine the difference between the two rollout values.
4. Subtract 30% of that difference from the 16T rollout.

This provides an estimated rollout for the 16.3T cog.

The same calculation applies to other decimal sizes. A 16.8T cog, for example, represents approximately 80% of the adjustment between a 16T and 17T cog.

Built for riders who demand precision, durability, and the ability to fine-tune every aspect of their BMX racing setup.