First ever chainsaw with STIHL Injection Technology. The best power-to-weight ratio on the market, and the simplest operation. Ideally suited to arboriculture and harvesting and processing large timber. All thanks to its unique lightweight design and outstanding acceleration. New bumper spikes, HD2 filter, captive nut on the sprocket cover for easy chain change, controlled-delivery oil pump, and tool-free fuel cap for safe and easy filling with fuels and lubricants.
STIHL 2-MIX engine
The two-stroke engine with STIHL 2-MIX technology saves up to 20 % of fuel and reduces emissions by up to 70 % compared to STIHL 2-stroke engines of the same performance class without 2-MIX technology.
HD2 filter with radial seal
The new HD2 air filter, made from PET material and featuring a radial seal, prevents the intake of fine dust particles. The hermetic seal increases the service life of the engine and reduces wear.
The decompression valve is part of the easy starting system. The valve should be pressed before starting to reduce the compression pressure when starting, as well as reducing the effort needed to pull the starter rope. The decompression valve is semi-automatic; it must be pressed manually before starting, but then closes automatically.
Due to compression pressure, jerky stresses occur when starting internal combustion engines. The damping element in the ElastoStart special starter grip alternately absorbs and releases force according to the compression pattern. The result is smooth, even starting.
Side-mounted chain tensioning
Side-mounted chain tensioning makes it easy to tension the chain safely.
Tool free fuel caps
Special caps to open and close the tank cap quickly, easily and without tools.
STIHL anti-vibration system
Precisely calculated buffer zones minimise the transfer of engine and saw chain vibrations to the front and rear handles. The chainsaw therefore runs noticeably smoother. This allows the user to save their strength and work longer.
When changing the cutting attachment, you will not risk losing the nuts on the sprocket. The MS 261 is the first STIHL chainsaw to be equipped with the captive nuts. A great advantage for all users.
Optimised sprocket cover
The flatter, narrower sprocket cover with integrated slide rails reduces effort when pruning and ensures outstanding chip removal.
STIHL Ematic with new oil pump system
The new oil pump system allows a higher volume of oil to be delivered. This is especially useful in dusty conditions or when using a long guide bar.
STIHL Injection (i)
STIHL injection technology enables the MS 500i to achieve extremely high performance with extraordinarily low displacement and low weight. The saw uses innovative technology to achieve rapid acceleration from 0 to 100 km/h in an unbelievable 0.25 seconds. The powerful saw is ready to use right away. Sensors measure air pressure and internal and external temperature, and pass information on to the control unit. This can use the identified values to determine the optimum fuel quantity and ignition timing.
Best power-to-weight ratio
Its revolutionary chainsaw engine technology, and resulting intelligent lightweight construction result in the best power-to-weight ratio on the market. The optimised design – with lightweight sprocket cover, more compact engine unit, flywheel with a low design height, and a reduced-weight crankshaft adapted to the low weight of the flywheel – makes work significantly more comfortable. The MS 500i is ideal for heavy timber felling, cutting into lengths, and pruning.
Very easy to start, whether starting from cold or
The starting process is perfect, with no need for a start position, and easy access to the purger.
Sensor-controlled fuel metering
In addition to the external temperature sensor, the MS 500i also has a pressure and internal temperature sensor in its engine. This measures the environmental pressure on start-up, and during operation it checks the engine temperature and pressure in the crankcase. The electrical voltage generator delivers the required speed information. The control unit processes these values, meaning that the system adapts to the conditions of use. The fuel is then dosed at the optimum level, quickly resulting in perfect running characteristics.
Marking has been added to the fan housing to assist with plunge cuts. This ensures better directional control and safe use of the machine during plunge cutting.
Optimised bumper spikes
The tooth length of the bumper spikes has been adjusted to account for the radial contours of trees. The saw bites into wood even better when cutting lengths and felling.
Technical data Value Displacement cm³ 79,2 Power output kW/bhp 5/6,8 Weight kg 1) 6,2 Power-to-weight ratio kg/kW 1,2 Sound pressure level dB(A) 2) 106 Sound power level dB(A) 2) 119 Vibration level left/right m/s² 3) 4,2/4