Tips & Solutions
What those numbers (415, 420, 428, etc.)
Each number refers to a chain size standard (ANSI/ISO) that defines three main measurements:
| Chain Size | Pitch (distance between pins) | Roller Diameter | Inner Width | Typical Use |
|---|---|---|---|---|
| 415 | 12.70 mm (½ inch) | 7.75 mm | 4.88 mm | Small underbone / moped / race mini-bike |
| 420 | 12.70 mm (½ inch) | 7.75 mm | 6.35 mm | 100 – 150 cc commuters |
| 428 | 12.70 mm (½ inch) | 8.51 mm | 7.75 mm | 150 – 250 cc street / touring bikes |
Pitch (½ inch = 12.70 mm) is common for all these sizes. Inner width is what differentiates them — it determines how wide the sprocket teeth and chain rollers are. Larger number = wider and stronger chain, suitable for higher torque or engine power.
How sprocket and chain relate
A motorcycle’s front (countershaft) and rear sprockets must match the chain size exactly.
A 420 chain fits only 420 sprockets.
A 428 chain will not fit a 420 sprocket (too wide).
Mixing them can cause rapid wear or even chain drop.
So:
Chain size → determines sprocket thickness & tooth profile.
Which size suits your 120 – 250 cc motorcycle
| Engine Size | Recommended Chain Type | Example Bikes |
|---|---|---|
| 100 – 125 cc | 420 | Yamaha Y15ZR, Honda RS150R (some), Modenas Kris |
| 150 – 200 cc | 428 | Yamaha FZ150i, Honda CBR150R, KTM Duke 200 |
| 200 – 250 cc | 428 or 520 (heavier-duty) | Kawasaki Ninja 250, Yamaha R25 |
| < 100 cc (underbone) | 415 or 420 | small cubs, race minis |
If your bike is a typical Malaysian 120 – 250 cc commuter/sport, 420 or 428 is almost always correct.
Check your owner’s manual or chain marking (often stamped on side plates like “DID 420D”) before buying.
Material & build tips
Steel vs Alloy sprockets:
Steel lasts longer; alloy (like 7075 T6 aluminum) saves weight for racing.O-ring / X-ring chains:
These use rubber seals to keep lubricant inside. Great for longevity, especially in Malaysian wet weather.O-ring = basic seal
X-ring = newer design, less friction, longer life
Non-sealed chains:
Lighter and cheaper, but require more frequent cleaning and lubing.
Maintenance & lifespan tips
Lubricate every 500 – 800 km, or sooner in rain.
Clean with kerosene (never petrol) + soft brush before applying new chain lube.
Maintain proper tension:
25–35 mm slack for most small bikes.
Too tight = stress on bearings; too loose = risk of skipping teeth.
Inspect for:
Tight links
Hooked sprocket teeth
Excessive chain stretch
Replace the set (chain + both sprockets) together to avoid premature wear.
Choose suitable Sprocket & Chain for your motorcycle
Need help choosing the right sprocket & chain? Visit our Sprocket & Chain products or Contact Us to discover the best combination. Whether you drive motorcycles with different brand, we offers a range of products from affordable to high quality that suits your favor and budget. Kindly ask us for the details. We always ready to serve you.
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