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2 Cycle or 4 Cycle Weed Eaters? The Facts

Weed eaters are the ideal machines for taking out the grass and weeds which are out of reach of your lawn mower. Once you decide you need to get one for your yard, the problem comes with choosing the right type. There are battery powered and gasoline powered weed whackers, straight and curved shafts weed whackers and 2 stroke/cycle and 4 stroke/cycle engine gasoline weed eaters.

Although there is a lot to consider in your final decision, we will only be looking at the differences between 2 cycle and 4 cycle weed eaters as well as their pros and cons in this article.

trimmer isolated
  • Differences

To begin with, it is important to mention that 2 cycle and 4 cycle stroke engines are only available in gasoline powered string trimmers. Electric weed eaters do not have any 2 cycle or 4 cycles stroke engines. This is a way of referring to a certain type of gasoline engine. Here are the major differences between the two types of engines of gas powered weed eaters: 

  • Power source and lubrication

Both engines are powered with gasoline. However, in two cycle stroke engines, the fuel and oil are mixed together to the right ratio suggested by the makers. In the four-cycle stroke engines, the fuel and oil are not mixed together. Each has its own tank.

  • Engine 

An internal combustion engine performs five functions before it will be able to complete its cycle. The five functions are air intake, air and fuel compression, ignition of air and fuel, air and fuel combustion and exhaust. A two stroke engine is so called because it takes two strokes of the piston to complete these functions. The crankshaft also revolves for one revolution before this cycle is completed. However, the four cycle engines take four strokes of the piston to complete these functions while the crankshafts revolve twice.

  • Weight and power

Two cycle engines almost always weigh less than four cycles engines. This is because in the structural designs of the latter, there are valves that needs a valve train, which will in turn add to the overall weight. However, given their weight, they generate more torque than two cycle engines and this makes them cut grass more efficiently and forcefully than two cycles engines.

  • Cost

Two cycle engines are more affordable than four cycle engines owing to the fact that it is less expensive to produce them. Two cycle engines come with fewer moving parts and this also makes them less expensive to maintain. However, the four cycle engines, which are more expensive to buy and maintain, are more durable and do not wear out easily. Two cycle engines consume more fuel and the spark plugs damages easily as the oil which is mixed with the fuel can ruin them.

  • Operation 

Four cycle string trimmers are harder to start than two cycles engines. Four cycle engines feature a crankcase from which oil is splashed up by the tabs on the bottom of the pistons into the cylinder. In other words, the trimmer with four cycle engines have to be kept closer to level to be properly lubricated. There is no crankcase in 2-cycle engine and thus it can be used at any angle suitable to the operator.

  • Pros and cons

Four cycle engines cut tougher grass more easily than two cycle engines because they generate more torque. However, they are more suitable for strong people and not ideal for everyone. Beginners and teenagers may not be able to trim grass with it for a long time because of the heavy weight. In other words, two cycle engines are easier to work with and are more suitable for learners than four cycles.

Two cycle engines make more noise and release more exhaust fumes to the atmosphere than 4 cycle engines. With increasing emphasis on the need to save the atmosphere as we are faced with the reality of global warming, it is more likely that the two cycle engine will be banned one day. Two cycle engines are budget friendly, but lack the powerful performance of 4 cycle engines.

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