The MS 661 C-M petrol chainsaw is an extremely powerful 5.4 kW professional saw designed for demanding forestry and large timber harvesting tasks. It features advanced STIHL 2-MIX technology, which reduces fuel consumption and exhaust emissions while maintaining high power output. The STIHL M-Tronic electronic engine management system automatically regulates ignition timing and fuel metering, ensuring optimal engine performance, fast acceleration, and sustained maximum torque under varying conditions such as temperature, altitude, and fuel quality.
MS 661 C-M is used in the STIHL TIMBERSPORTS series.
Starting the MS 661 C-M is effortless, thanks to the decompression valve, which reduces the force required on the starter cord and protects the start-up system. The combi lever with stop function simplifies operation by allowing the control lever to return automatically to the operating position for quick restarts.
Durability and low maintenance are enhanced by the HD2 filter, which traps even fine dust particles and is both oil and water-repellent, making it easy to clean. The compensator system keeps engine performance and fuel consumption stable over time, reducing the frequency of air filter cleaning. The chainsaw also includes captive nuts on the sprocket to prevent loss during cutting attachment changes.
Comfort during extended use is ensured by the STIHL anti-vibration system, which reduces vibrations transmitted to the handle area, making the tool easier to control and less tiring to use. The STIHL Ematic system minimizes oil consumption by delivering precise lubrication to where it’s needed, reducing oil use by up to 50%. For easy maintenance, the side-mounted chain tensioning system provides secure and simple chain adjustments, while the variable-displacement oil pump allows the user to adjust oil flow based on cutting conditions.
With a tool-free fuel cap, refueling is quick and hassle-free. The MS 661 C-M is built to be robust, durable, and efficient, making it a top choice for professional forestry work.
Not guarenteed to be supplied with pictured guide bar. Exterior design of STIHL guide bars are subject to change. Technical specifications remain the same.
MS 661 C-M High Performance Forestry Chainsaw
Owner's Manual
Find information about Set Up, Operation, Maintenance, Storage and find Product FAQ's and Owners Manual for this product here:
You can find videos showing you how to fill your machine with fuel and oil, fit bars and chains and start your chainsaw here:
Technical Specifications
Displacement 91.1 cm³ Power output 5.4/7.3 kW/HP CO2 679 g/kWh Weight 7.5 kg 1) Weight 9.22 / 10.38 kg 2) Power-to-weight ratio 1.4 kg/kW Bar length 71-90 cm Bar length 28-36 " Saw chain pitch 3/8 " Length with bumper strike 467 mm Sound pressure level 105 dB(A) 3) Sound power level 118 dB(A) 3) Vibration values left/right 6.9/5.6 m/s² 4)
1)Without fuel, without bar and chain2)Without fuel, with bar and chain3)K-factor according to DIR 2006/42/EC = 2.5 dB (A)4)K-factor according to DIR 2006/42/EC = 2m / s ²
