ProTaper – ProTaper Rear Sprockets - ATV, including CS4 steel rear sprockets for Suzuki LTZ400, LTZ450 and LTR450, Kawasaki KFX, Arctic Cat DVX, Honda TRX250R and Yamaha YFZ450 and YFM models, is built around one hard truth: quads are heavy, and quad chains work far harder than dirt bike chains. That is why this group leans on CS4 steel rear sprockets rather than lightweight aluminum, with tooth counts from 36 to 40 teeth so you can trade launch punch against top speed on sand, dunes, TT tracks or trail. Coverage includes the Suzuki LTZ450 and LTR450, shared Arctic Cat DVX / Kawasaki KFX / Suzuki LTZ400 fitments, 08-14 Kawasaki KFX450, the classic 93-08 Honda TRX250R in 37, 38 and 39 tooth sizes, and 04-up Yamaha YFM250/350/700 and YFZ450 machines. Steel resists the abrasive blasting that sand and mud deliver behind a spinning rear tire, so tooth profiles stay square and the chain keeps riding on full-depth valleys instead of hooked, worn stubs. Correct gearing also keeps the engine off the rev limiter and reduces heat in the driveline. A precise ProTaper rear sprocket delivers consistent drive, steadier chain tension, and long service life.