Stihl 3/8" 7 Tooth Spur Sprocket - MS461, MS461R

Restore max power transfer, crisp clutch engagement, and reliable chain drive performance to your heavy-duty chainsaw with the Genuine OEM STIHL 3/8" 7-Tooth Spur Sprocket Drum Kit (Part #1128 640 2003). Designed as a solid, direct-fit replacement, this heavy-duty steel drum assembly replaces worn, grooved, or heat-damaged drive components—stopping chain chatter, drive link burring, and clutch slippage instantly.

Why Choose Genuine OEM over Aftermarket? Commercial-grade 70cc+ powerheads exert extreme rotational stress on drive components. Cheap aftermarket spur drums frequently suffer from out-of-round machining, soft metal drive teeth that groove prematurely, and improper drum wall tolerances that cause rapid clutch pad wear. STIHL OEM assemblies guarantee exact dynamic balance, precise needle bearing fitment, and long-lasting commercial durability.

What's Included

• (1) Heavy-Duty Clutch Drum with Integrated Fixed Spur Sprocket
• (1) Precision Clutch Washer
• (1) Factory E-Clip Retaining Ring

Key Features

• 100% Genuine OEM STIHL Quality: Built to exact factory specifications using high-density, heat-treated structural steel alloys to guarantee maximum service life under severe cutting loads.
• High-Torque 3/8" Pitch 7-Tooth Gearing: Calibrated specifically to maximize pulling force through dense hardwoods, large log bucking, and heavy timber felling.
• Induction-Hardened Steel Teeth: Precision-ground spur teeth resist frictional grooving, keeping chain drive links meshing smoothly and safely.
• Integral One-Piece Drum Design: Combines the clutch drum and drive spur into a single rigid unit for simple, drop-in replacement during routine maintenance.
• Complete Replacement Hardware: Includes required drive line washer and retaining clip to ensure a fast, reliable installation.

Product Specifications & Compatibility