Boiler horsepower, Metric horsepower, Electrical horsepower, Drawbar horsepower, Shaft horsepower, SAE horsepower, Brake horsepower. And that’s just to name a few types of horsepower. All these horsepower terms relate to the measurement of force or power. Accurately, today the "horsepower" force concept is measured in kilowatts, Newton minute, and foot pound minute. 1 hp = 33,000 ft/pound-force/min = exactly 745.69987158227022 Watts. There is an interrelationship with the "horsepower" force concept and a force known in physics as torque. Torque can informally be thought of as a "rotational force". The Greenfield Mowers clutch drive (invented by Theo Reinhold in 1966) offers high torque due to the kinetic energy, which is easily stored in the GT401 12-inch drive pulleys. These pulleys are massive when compared to the size of a Greenfield Mowers ride-on. Due to the instantaneous power transfer afforded by the ingenious clutch engagement the Greenfield Mowers ride-on has an extremely high torque capability.

This is the reason why the Greenfield Mowers ride-on has extraordinary power for tough slope and towing work. The Greenfield clutch pulleys counter rotate, one pulley forward, and the other reverse. By selectively engaging either pulley with the pivoted clutch pedal, a smooth variable speed forward or reverse is obtained. The drive force is transferred to the back axle by an extra strong roller chain and sprocket. Mechanical horsepower for engines is based on a calculation originally proposed by James Watt in 1782. Initially, he proposed that this power unit be based on a horse's ability to lift a one ton load up a straight mineshaft. Watt had immediate problems with his proposal. He recognized that a horse, being an animal, can by effort vary its "horsepower" from 20,000 to 140,000 ft/pound-force/min. Basically, "horsepower" is a 19th century unit of measure relevant when most people were using a horse for everyday power. It's an interesting fact that horse numbers on Australian farms were highest in the early 1920's.

At that time, the best reason for not investing in steam or combustion engine machinery was that it couldn't reproduce itself. The idealism of picturing 500 horses pulling a car around the racetrack is romantic and lives on especially in the automotive industry. Many countries no longer acknowledge horsepower as a lawful unit. These complex considerations mean that most small engine manufacturers will rely on quoting cubic capacity of the engine rather than referring to a "horsepower”. Because of the power efficiency from our clutch drive and the performance of the Fastcut cutting deck the Greenfield Mowers ride-on needs a much lower horsepower engine than an imported ride-on. A straight comparison of engine horsepower/size of cut is not a great consideration when buying a ride-on mower especially when comparing to a Greenfield Mowers ride-on.

Yet it will provide a very even, sharp cut on fine, manicured lawns.

Very often we are asked by customers if our mower will cut a certain type of tough weed or grass. It has been our experience that the Greenfield ride-on will cut ALL of the tough vegetation. There are many reasons why the Greenfield Mowers ride-on will cut tough high grass better than any other ride-on. Firstly, we only use our Fastcut single rotor cutting deck. This allows for superior grass ejection in heavy going. Having a single cutting disc, as opposed to two or three, concentrates the power where it’s needed: at the two cutting blades. You not only obtain a faster, cleaner cut first time, you will save season after season on parts replacement and maintenance because there’s just one spindle housing, one cutter disc and two blades.

Ask your customer to compare the cost of American bar blades to the low cost Greenfield Mowers swing back blades. On paper, a mower with a 40-inch deck and two or three cutting discs should get the job done faster. However, there is substantial loss of blade horsepower due to extra friction and congestion to flow the cut of grass. In heavy going nothing beats a single cutter deck. Don’t forget the single rotor deck is the best way to obtain a sharp, even cut on nice lawns – with less overlap and no “mow-hawking”.

Another reason for the superb cutting ability of the Greenfield Mowers ride-on is the unique power drive, which allows more power to be available for cutting. No other ride-on equals the Greenfield for simplicity, ease of use and most importantly, positive traction in all mowing conditions.