Carkio Centrifugal Clutch for Go-Kart — 3/4" (20mm) Bore, 10-Tooth for #40/41/420 Chain, Black

The Carkio Go Kart Centrifugal Clutch is a durable 10-tooth, 3/4" (20mm) bore aftermarket clutch designed to drive #40/41/420 chain on small engines up to 8hp.

This compact centrifugal clutch gives hobbyists and small-vehicle builders a simple, bolt-on solution to transfer power from the crankshaft to a chain-driven rear axle or sprocket. Built from metal with a black finish and a 107mm outer diameter, it is engineered for typical 3.5–7hp engines and can tolerate up to about 8hp under common operating conditions. It includes a 3/16" key and matches standard #40/41/420 chain sizes used across go-kart and minibike setups.

How does this clutch engage and protect my engine?

The centrifugal design automatically engages as engine RPM increases, so the vehicle remains stationary at idle and begins driving as revs rise. This reduces stalling and provides gradual power transfer for smoother starts. It also isolates the engine from sudden load changes compared with a direct drive connection.

• Engages automatically with increasing RPM for smooth starts
• Built-in 3/16" key ensures secure crankshaft coupling
• Mounts on the crank with a bolt and washer for straightforward installation

Will this clutch fit my engine and chain setup?

Measure the engine crank bore and confirm the chain size before ordering; this clutch has a 20mm (3/4") inner bore and is sized for #40, #41, and #420 chains. It is commonly used on 3.5–7hp engines—practical for many go-karts, minibikes, and small utility machines. If your crank requires set screws or a different bore, consider a model designed for those features.

• Inner bore: 20mm (3/4") — verify crankshaft diameter
• Chain compatibility: #40, #41, #420
• Commonly suited to engines up to 8hp; check engine RPM and application

How do I install and maintain the Carkio centrifugal clutch?

Installation is straightforward: slide the clutch onto the crankshaft, align the 3/16" key, and secure it with the crank bolt and washer. Basic maintenance includes periodic inspection of the shoe surfaces, chain alignment, and fastener torque. Keep the clutch free from excessive dirt and debris to preserve engagement performance.

• Simple bolt-on mounting to the crankshaft with included keyway
• Inspect shoes, bearings, and keyway for wear every few hours of run time
• Maintain proper chain tension and alignment to prevent premature wear

What are the physical specifications and what’s included?

The clutch measures approximately 107mm outer diameter with a total height near 55mm and contains 10 teeth for the sprocket interface. It ships as a single aftermarket centrifugal clutch unit and is finished in black metal. Because it is an aftermarket component, confirm measurements and fit before installation to ensure compatibility.

• Material: metal with black finish; outer diameter: 107mm; height: ~55mm
• Teeth: 10; bore: 20mm (3/4"); built-in 3/16" key
• Package: 1 x Carkio Go Kart Centrifugal Clutch (aftermarket compatible)

Who is this for: This Carkio centrifugal clutch is aimed at DIY go-kart and minibike builders, repair shops, and small-engine hobbyists who need a reliable, affordable aftermarket clutch for chain-driven setups. It’s best for users who can verify shaft and chain dimensions, want a simple bolt-on solution, and value a robust metal clutch that handles routine recreational and light utility use.