Stihl 3/8" Picco 6 Tooth Spur Sprocket Kit - 017, MS170, MS180

Restore optimal power delivery and responsive throttle engagement to your light utility chainsaw with the genuine OEM STIHL 3/8" Picco 6-Tooth Spur Sprocket Kit. Specially engineered to match the precise power bands of light-duty and top-handle trim saws, this factory clutch drum is a direct replacement for the 017, 018, MS 170, MS 180, and MS 191T series platforms. Replacing a hooked or deeply grooved drive drum is essential to prevent rapid chainsaw chain wear, engine bogging, and dangerous erratic clutch engagement at idle speed.

This premium original equipment manufacturer spur sprocket features a precision weld-bonded 6-tooth drive gear structurally integrated into a heavy-duty stamped steel drum shell. The 6-tooth geometry is optimized to keep engine RPMs high and punchy inside smaller displacement engines, transferring maximum torque to your cutting loops. Case-hardened to prevent premature tracking, this spur sprocket guides the chain chassis smoothly off the clutch face, reducing structural chain slap and stabilizing high-speed wood cutting.

True OEM Steel Performance vs. Soft Aftermarket Metal: Budget aftermarket drive drums are notorious for using un-hardened metal that deforms or hooks drive links within a few tanks of fuel. Imprecise non-OEM machining leads to loose inner diameter tolerances, causing harmonic crankshaft vibrations that rapidly destroy the needle cage bearing, the oil pump drive gear, and internal clutch springs. A genuine STIHL sprocket ensures perfectly round concentricity and tight tolerances to guard your powerhead internals.

Configuration & Safety Note: Designed exclusively for models configured with a 3/8" Low Profile (Picco) pitch chain loop (.043" or .050" gauge). This setup will not accept .325" pitch or full-profile 3/8" professional skip/semi-chisel chain. This factory kit consists of the genuine 6T spur sprocket drum body ready for direct drop-in installation.

Key Features & Benefits

• Precision-Formed 6-Tooth Design: Engineered to provide the ideal gear ratio for compact engines, maximizing cutting velocity without overloading the motor.
• Integrated Spur Sprocket Drum Structure: Heavy-duty unified construction provides exceptional concentricity and prevents misalignment under peak compression.
• 100% Genuine OEM STIHL Manufacture: Built to precise factory metallurgy standards using proprietary heat-treated steel for extended wear resistance.
• Smooth Chain Delivery Tracks: Hardened guide faces accept chain drive links evenly to mitigate high-speed friction and chain stretch.
• Perfect Needle Cage Alignment: Inner bore diameter matches factory crankshaft tolerances exactly to keep drum rotation balanced and vibration-free.
• Drop-In Service Convenience: Direct factory retrofit part to get your property maintenance or commercial pruning crews back to work without field alterations.

Technical Specifications & System Components