Product overview This complete clutch drum and sprocket rim kit replaces worn drive components to restore reliable chain engagement and smooth power transfer. The kit contains the key parts needed for clutch and sprocket replacement or field repairs on compatible chainsaw models. Key benefits Restores chain drive performance: Replaces worn drum and sprocket rim to reduce slipping, uneven chain movement, and excessive vibration. Saves time on repairs: Supplied as a readytoinstall kit with the drum, sprocket rim, needle cage, washer, and clip needed for reassembly. Precise fit: Matches the original part geometry to ensure correct engagement with the clutch and chain drive train. Useful for maintenance and rebuilds: Ideal for routine replacement when sprocket teeth or drum surfaces show wear. Function and important attributes Function: Clutch drum and sprocket rim assembly for transmitting engine torque to the chain via the clutch and sprocket interface. Compatibility: Compatible with the following chainsaw models for replacement use: 064, 066, MS640, MS650, MS660, MS661, MS640R, MS640RW, MS640W, MS650 Magnum, MS650R, MS660 ARCTIC, MS660 Magnum, MS660W. Replacement part number: 1122 007 1002 Key specifications: Spur pitch: 0.404 inch Spline count: 7 Total height: 34.2 mm Hole inner diameter: 16 mm Drum inner diameter: 81.9 mm Package contents 1 x Clutch drum 1 x Sprocket rim 1 x Needle cage 1 x Washer 1 x Clip Typical applications and scenarios Onthetrail : a damaged or worn sprocket rim and drum during field maintenance to get the saw back into service quickly. Workshop rebuild: Use as part of a clutch and drive train overhaul to restore smooth chain speed and reduce vibration on higher hour machines. Preventative maintenance: Fit the kit when sprocket teeth show visible wear or the drum surface is scored to avoid further drivetrain damage. Installation notes Confirm compatibility with the listed models and the replacement part number before installation. Inspect adjoining components such as the clutch, chain, and drive sprocket for wear and as needed to ensure performance. This kit contains the components needed for a direct replacement of the clutch drum and sprocket rim assembly for the listed chainsaw models.