YOXUFA 60-Tooth Rear Sprocket & 420 Chain Kit (90-Link) — Drop-In Replacement for Coleman CT200U and Mini Bikes

YOXUFA's 60-tooth rear sprocket bundled with a 420-series 90-link chain is a drop-in replacement designed to restore drivetrain strength and deliver a higher top-end for compatible mini bikes.

This complete kit replaces worn rear sprockets and chains on a range of small-frame powersports machines, including Coleman CT200U series, Baja and TrailMaster mini bikes, and many 196–212cc single-cylinder engines. It includes the sprocket, a full 420 chain with master links, mounting nuts, and a chain breaker so you can fit and size the chain at home or in the shop. The parts are machined to fit common mini bike hubs and are intended to change final gearing for a speed-focused setup while maintaining reliable engagement with OEM front sprockets.

Will this sprocket and chain fit my mini bike model?

Compatibility covers a broad list of small-engine mini bikes and kits that use 420-series chains. Confirm your bike currently uses a 420 (sometimes labeled #40 or #41) chain and has the hub bolt pattern matching the 11 mm mounting holes and a 40 mm center bore before ordering.

• Fits Coleman BT200X, CT200U, CT200U-EX models.
• Compatible with Baja Motorsports MB165 and MB200 (Heat, Mini Baja, Warrior).
• Also works with Hensim MB165/MB200, MASSIMO MB200, TrailMaster MB200, Axis M200.
• Sprocket center hole 40 mm, mounting hole diameter 11 mm — verify against your hub.

How does a 60-tooth rear sprocket change performance?

Moving to a larger rear sprocket alters the final drive ratio toward more speed at the wheel for a given engine RPM, often providing higher top speed and smoother highway cruising compared with smaller rear gears. It can reduce engine load in some setups, but actual effects depend on the front sprocket size and engine characteristics.

• 60 teeth increases circumference for longer travel per wheel rotation.
• Pairs with a 420 chain to keep tooth engagement stable under load.
• May improve top-end speed while modestly altering acceleration feel.
• Not a guaranteed power increase — results vary with engine and front sprocket ratio.

What comes in the YOXUFA replacement kit and what tools are needed?

The kit supplies everything required to mount and size the chain and install the sprocket—ideal for a home mechanic. Basic hand tools plus the included chain breaker are enough to complete the job safely.

• Included: 1 x 60-tooth 420 sprocket, 1 x 420 chain (90 links).
• Also included: 5 x 420 master links, 4 nuts, and 1 chain breaker tool.
• Recommended tools: socket set, torque wrench, screwdriver, and pliers.
• Check chain tension and torque specs on install to avoid premature wear.

What are the key dimensions and materials to verify before buying?

YOXUFA provides the sprocket and chain dimensions so you can match them to your bike’s drivetrain. Confirm the chain series and the hub mounting measurements to ensure correct fitment and safe operation.

• Chain size: 420 series (sometimes listed as #40 or #41).
• Sprocket teeth: 60; overall diameter approximately 245 mm (9.64").
• Center hole diameter: 40 mm (1.57"); mounting hole diameter: 11 mm (0.43").
• Chain length: 90 links, adjustable with included chain breaker and master links.

Who is this for: This YOXUFA kit is aimed at DIY mechanics, mini bike enthusiasts, and small-powersports owners who need a durable replacement rear sprocket and a full 420-series chain. It suits riders who want to modify gearing for higher top speed or simply restore drivetrain reliability on Coleman, Baja, TrailMaster, Hensim, MASSIMO, Axis, and similar mini bike platforms running 196–212cc engines. If you’re unsure about fitment, measure your current sprocket center bore, mounting hole spacing, and confirm the chain series before purchase.