Compact chainsaw with good power-to-weight ratio and hard-wearing STIHL Rapid Duro 3 low-profile saw chain. With up to 20% less fuel consumption and up to 70% fewer emissions compared to STIHL two-stroke engines of the same performance class without 2-MIX technology. Easy to guide, great handling. With STIHL Quick Chain Tensioning, STIHL Easy2Start and QuickStop Super. and Rapid Duro 3 stay sharp chain, 10x longer sharpness than standard chain.
STIHL MS 251 C-BEQ Wood Boss® Chainsaw Rapid Duro
Displacement cc 45.6 Power output kW/bhp 2.2/3 Weight (kg) 5.2 Vibration level left/right m/s² 3.9/3.9 STIHL Oilomatic saw chain pitch/type 0.325
Easy starting with less effort due to an additional spring between the crankshaft and the rope rotor. A smooth pull on the starter rope tensions the spring against the compression resistance of the engine. The jerks are not transmitted to the rope. The spring automatically transmits the stored energy to the crankshaft, causing it to turn and ensuring reliable starting of the engine.
Pre-separation air filtration system
The innovative long-life air filter system greatly extends the service life of the filter. Air routing removes larger particles of dirt, meaning the actual filter has less to do. So the saw can be used for longer without having to clean the filter.
STIHL 2-MIX Engine
The new 2-MIX engine features an advanced stratified charge system that boosts power, whilst reducing consumption and pollution, significantly lowering unburned hydrocarbons in the exhaust. The result is a cleaner, more fuel efficient engine.
This controller in the carburettor prevents the fuel-air mixture getting richer as the air filter becomes clogged. The correct quantity of fuel is delivered to the carburettor depending on the quantity of air passing through the air filter. This keeps the fuel/air ratio in the combustion mixture constant and hence also the engine power. The filter doesn't need to be cleaned until an appreciable drop in power occurs.
Manual fuel pump (Purger)
A small fuel pump delivers fuel to the carburettor at the touch of a button. This reduces the number of starting strokes required from a cold start.
Intense vibration at the handles of power tools can lead to longer-term effects of blood vessels in the hands and arms. STIHL have therefore developed an effective anti-vibration system where by the oscillations from the machines engine are dampened which significantly reduces vibrations at the handles.
Single-lever master control
All important functions such as start, choke, throttle and stop are operated via a single lever.