Technology

4-Stroke Over 2-Stroke

The City Councils have, as part of their re-tendering process, conducted product comparisons over a set period of time comparing the performance of their current 2-stroke products with Honda products.

In regards to fuel useage the comment has been that the 4-stroke Mower uses approximately half the fuel of a 2-stroke equivalent size Mower.

Experienced Mowing Contractors recognised this a long time ago and have told us that the fuel savings are even better than half.

Similar comments have been forthcoming where Brushcutters have been similarly tested by both groups. Our calculations, based on estimates of hours of use supplied by Mowing Contractors, indicates that Contractors can obtain a new Brushcutter free of charge every two years due to fuel and oil savings. The same would apply to Mowers.

We can not assume the same product replacement for Blowers and Hedgecutters though because the useage of these products is not as great.

Noise is another significant issue, particularly for bystander and building occupants nearby. The operator is able to wear ear muffs but this is not normal for persons in the surrounding locality. Examples given by Councils and Contractors are shopping centres, doctors and dentist surgeries, schools, kindergartens, hospitals and elderly persons homes etc. This applies to all products mentioned above but particularly to Brushcutters, Blowers and Hedgecutters because they have small mufflers (to save weight) emitting a high pitched scream.

Pollution is another environment evil where hydrocarbons particularly are harmful to the operator (OH&S) and the community.

Contractors who previously complained of headaches when using Hedgecutters for extended periods, have found that the headaches are less when using a 4-stroke product. This is because Hedgecutters are regularly used at head height.

Comments regarding ease of starting of 4-stroke products becomes more significant as the age of the product increases. This is largely due to the fact that unburnt oil build up in the spark plug, ports and mufflers of 2-stroke products, makes them difficult to start, resulting in over choking and further starting problems - results in poor chamber firing, a build up of back pressure and carburetor flooding respectively. This applies to all products mentioned above.

The NSW Environment Protection Authority has recently called industry representatives together for a meeting to address the pollution and noise issues.

This involves both 2 and 4-stroke manufacturers/importers in the Power Equipment Industry. No doubt their findings will influence the future direction of portable power equipment, for the wellbeing of consumers and the environment, into the future. Here 4-stroke products have a significant start on 2-stroke products.

The engine torque or power of a 4-stroke provides increased performance, particularly under heavy operating load, compared with a 2-stroke. This is due to a "flatter" torque performance curve in a 4-stroke. The engine revolutions for peak performance are more critical in a 2-stroke. This means that the 2-stroke engine, under heavy load conditions is less responsive, particularly where air filters are poorly maintained.

We apologise that we have not retained testimonial details with names and addresses that may offer credibility and or contacts for interested parties. We have been satisfied that the 4-stroke products, in an increasingly environmentally conscious market place, have been favourably received based on experiences and tests carried out by independent consumers. In the end the product must stand on its own reputation rather than any "spin" offered by a manufacturer or importer.