The new maximum

STIHL 2-MIX engine

Green machine: the efficient STIHL 2-MIX engine with 1-in-4 channel technology delivers high torque over a wide rpm range. At the same time, the STIHL MS 661 C-M consumes up to 20%* less fuel and produces as much as 50%* lower emissions.

*Compared to STIHL 2-stroke engines of the same performance class without 2-MIX technology

STIHL M-Tronic control unit

The M-Tronic fully automatic engine control makes work easier, even for the pros. A microchip controls the engine's ignition timing and fuel supply, taking into account variables such as temperature, fuel quality and elevation. So you no longer need to manually adjust the carburettor, the chain saw consumes less fuel and you can count on the best possible engine performance at all times.

Low power-to-weight ratio

Light years ahead: the STIHL MS 661 C-M is the lightest professional-grade chain saw in its displacement class. Special components significantly improve the power-to-weight ratio, such as the stainless steel muffler and the Rollomatic ES guide bars.

Combi-lever with stop button function

M-Tronic automatically distinguishes between a cold or warm start, so there is only one start position on the combi-lever. The exact amount of fuel needed for each kind of start-up is provided automatically. So you can power up to full speed straight away, even after a cold start. After the saw is turned off, the control lever immediately moves back into the operating position.

New STIHL anti-vibration system

Steady does it: we've developed an innovative new anti-vibration system for an even more controlled and precise cut. It significantly reduces the vibrations felt by the user.

Double bumper spikes

Above average: double bumper spikes ensure great cutting precision during bucking and felling jobs. For better directional control during plunge cutting jobs, raised lines that act as plunge guides have been integrated into the crankshaft design.

STIHL Ematic with new oil pump system

The new oil pump system enables the oil flow to be increased, which is particularly advantageous when working in dusty conditions or when using longer guide bars.

New HD2 filter with radial seal

The new HD2 air filter made of PET material with a radial seal prevents fine dust from entering the chain saw. The hermetic seal increases the engine's service life and reduces wear.