Product Catalog 
When it comes to motorcycle chains, numbers like “420” and “428” are not just product codes—they are standardized specifications with real technical meaning.
The first digit (e.g., “4”) refers to the chain pitch, which is the distance between pins.
4 × 1/8 inch = 12.7 mm pitch.
The last two digits (e.g., “20” or “28”) represent the inner width of the roller link, which is the space where the sprocket fits.
In short:
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420 chain = Pitch 12.7 mm × Inner Width 6.35 mm
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428 chain = Pitch 12.7 mm × Inner Width 7.938 mm
■ Performance and Use Case Differences
The D.I.D 420 chain is lightweight with low friction, making it ideal for small motorcycles, scooters, and racing go-karts.
In contrast, the 428 chain is designed for mid-size motorcycles and is thicker and stronger, capable of handling higher torque and power.
Even though the pitch is the same, the sprocket fitment is different, meaning 420 and 428 chains are not interchangeable.
Installing the wrong chain can cause poor engagement, increased wear, or even chain derailment during riding.
■ Why Choose D.I.D Chains?
D.I.D is a trusted Japanese brand used by professional racers and major motorcycle manufacturers around the world.
All D.I.D chains meet high standards for durability, precision, and performance.
When selecting a chain, always check your bike’s specifications first.
Then, choose a genuine D.I.D product to ensure safety, longevity, and a smooth ride.