AS 901 SM

Professional flail mulcher with a high work rate

The AS 901 SM delivers high work rates and perfect handling whether on slopes, in dense growth or high grass. A Briggs & Stratton Vanguard Series 2-cylinder engine with 480 ccm displacement, up to 16.0 hp and an oil and fuel pump performs in tough conditions without the risk of engine damage. Propulsion occurs via a 5-speed manual transmission with reverse gear (1.8 km/h) that covers a speed range from 1.2–4.0 km/h. The rear axle differential is permanently locked, resulting in excellent traction even on wet grass. Twin tyres ensure even greater traction and stability while a vertically installed engine provides a low centre of gravity and balanced distribution of weight, at a total of 215 kg.

Operation is simple, convenient and safe

The AS 901 SM is conveniently operated via four levers. Individual wheels are controlled via a patented steering and brake clutch system by which light pressure on the wheel’s respective operating lever opens the limited slip differential; full pressure activates the brake on that wheel. Furthermore, the limited slip differential is permanently locked when in drive and the automatic parking brake engages as soon as the drive lever is released. This added safety feature stops the flail mower whether on a slope or level ground. Teflon-coated stainless steel Bowden cables ensure minimal expenditure of force. The result is safe, simple, and convenient operation.

Robust flail mowing unit

With a robust 90 cm wide flail mowing unit equipped with 26 pairs of Y-flails, the AS 901 SM is engineered for harsh conditions. The flail mower can cut grass up to 130 cm high at work rates reaching 3,600 m² per hour. The flail mowing unit is supported by pendulum bearings, delivering uniform mulching results by compensating for uneven terrain. The flails ride up and over obstacles, protecting both the engine and the operator from damage. A perforated impact guard provides additional safety. Cutting height can be adjusted to 6 levels from 10–100 mm, while the operating bar can be conveniently adjusted laterally and in height to match both the operator and the conditions.

Product advantages

Performs on slopesExtra fuel and oil pump with oil pressure switch optimize performance on slopes.
Robust flail mower unit (AS 901)Pendulum-bearing supported flail mower unit with 26 pairs of Y-flails for high work rates and an extremely clean mulching result.
Automatic parking brakeWhen the drive lever is released the machine stops automatically, whether on a slope or level ground.
Steering and brake clutchSingle-wheel brake controls the device precisely and effortlessly.
Permanent limited slip differentialPermanently locked limited slip differential opens only when steering with the steering and brake clutch.
Lightweight and balancedStable, lightweight construction with double-wall mower deck and rigid square frame. Low centre of gravity for optimal slope performance.
Thrown object test (AS 901)Tested in accordance with DIN EN 12733:2011-06.

Product details

Height adjustment

Easy cutting height adjustment with lever.

Manual transmission

5-gear manual transmission with limited slip differential and reverse gear for excellent propulsion, even on wet grass.

Adjustable operating bar

Guide bar can be adjusted laterally and in height to adapt to the size of each operator.

Impact guard

A perforated impact guard ensures a high level of operator safety.

Technical Data

cutting width 90 cm
maximum grass height 130 cm
engine manufacturer Vanguard
engine designation V-Twin
4-stroke engine, 1-cyl. / 2-cyl. /
displacement 480 cm³
maximum power 11,9/16,0 kW (hp)
rated power 10,7/14,5 kW (hp)
rated speed 3500 rpm
starting device, manual / electric /
drive, mechanical/hydrostatic /
number of gears 5
reverse gear
max. speed 4 km/h
automatic parking brake
limited-slip differential
blade clutch, electric / mechanical /
closed mowing deck
flail pairs 26
flail shape, Y / hammer /
cutting height 10 - 100 mm
both sides of the flails can be used
tank capacity 5 l
dimension L/W/H 220x104x105 cm
weight 215 kg
Changes in technology, equipment and price are reserved. Of information or illustrations no claims can be derived.


Steel hand guard set

Additional protection for the operator.

Steel wheels, climbing aid

Improved traction, particularly when mowing diagonal to slopes.

Operating hour meter

Documentation of work hours.

Tilt meter

Convenient display of slope incline.

Liquide tyre sealant “Plattfuss-Stop”

Seales promptly on and off punctures in all pneumatic tires and stops creeping pressure loss. Reduces the failure times due to flat tires.

More information »


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