KAMIER 420 Drive Chain 102-Link Kit — 50–125cc Mini Bike/ATV Replacement with Chain Breaker & Master Links

The KAMIER 420 drive chain is a 102-link replacement chain kit with a chain breaker and extra master links designed for 50–125cc pit bikes, mini bikes, ATVs and go-karts that use 420 sprockets.

Whether you need a full replacement chain or a service kit to fit a variety of small-displacement Chinese and OEM mini motorcycles, this KAMIER package includes the chain, a hand chain-breaker tool and spare master links so you can size and install it yourself. It’s built to match the 420 sprocket pitch and comes long enough to trim to fit many popular 50cc–125cc models commonly found on TaoTao, Coolster, SSR, Baja and Honda/Kawasaki/Yamaha/Suzuki small bikes.

Will this chain fit my pit bike or mini ATV?

Check that your bike uses a 420 sprocket set and confirm required link count after removing the old chain. This kit is made to work with many 50–125cc 4-stroke bikes and quads, but it will not fit rear 428 sprockets.

• Compatible examples: CRF50, XR50, KLX110, PW80, TTR90, SSR 70/110/125, DR-Z110.
• Chain spec: 420 pitch with 102 links (51 internal + 51 external links).
• Does not fit 428 rear sprockets—measure sprocket teeth or old chain pitch first.

How do I adjust the chain length during installation?

The included chain breaker tool removes or adds links so you can achieve proper tension and route. Use the master links supplied to reconnect the chain and verify length by mounting the chain on both sprockets with the suspension loaded.

• Package includes one chain breaker tool and 10 master links for repeated adjustments.
• Remove links until correct slack is reached—typical mini bike slack depends on swingarm travel.
• Double-check alignment and torque before riding; re-check tension after the first rides.

What durability and maintenance should I expect?

Small-displacement drive chains experience wear from dirt, load and lubrication—regular cleaning and proper lubrication extend life. This replacement chain is sized and finished to match typical OEM mini-bike requirements, but service frequency depends on riding conditions.

• Lubricate frequently in dusty or wet environments to reduce wear.
• Inspect for tight links, rust or elongation and replace if excessive wear appears.
• Keep sprockets in good condition—worn sprockets accelerate chain wear.

Who is this for: Riders, hobbyists and small-shop mechanics who maintain 50cc–125cc pit bikes, mini bikes, go-karts and ATVs and need a ready-to-install 420 chain kit. If you own or service TaoTao, Coolster, Baja, SSR, Honda CRF50/XR50, Kawasaki KLX110, Yamaha PW80/TTR models or similar Chinese mini motorcycles and require a full-length chain with installation hardware, this KAMIER kit provides the parts and a hand tool to size and fit the chain yourself.