Just this summer, I purchased my first self-propelled mower. Now, I have to admit that it was used (but a great deal and in good shape) and that I still had some things to learn about it. Although it was “self-propelled,” it wouldn’t do all of the pushing and pulling. And, as it was a model from a few years ago, operating by a small disc that controlled the front, right wheel. So, the mower was front-wheel drive.
Self-propelled mowers operate under the same safety premise that regular trimmer mowers do. They have to have a safety bar, which is a sort of kill switch that will automatically stop the mower once the bar is disengaged. So, there are now two bars to hold, even with newer models. The first is a safety bar from the blade. By law, with the use of a kill switch, blades and the motor have to come to a complete stop within four seconds. The second bar controls the mower should it be self-propelled. Disengaging this bar will not stop the motor or blades, but will halt its forward procession.
Most units in this category will not hinder your ability should you want to mulch, bag or discharge clippings. Some of the safer units that I’ve seen actually have a guard protecting whichever wheel is doing the pushing (or in most cases, the pulling). You want to be sure that children and animals stay completely away from the machine. You especially don’t want to allow your child or adolescent to control the machine should s/he not be big enough or responsible enough to control the unit. Self-propelled models can gear a lot of horses (up to 6- or even 10-hp) that can get away from those without enough control or strength.
Most of these mowers now use a drive mechanism that is much safer and not exposed. The higher-end models allow you to control the speed gradually, while others will jump the instant the bar is engaged. Prepared for take-off, the machines can be abrupt. And, some units are a little tricky to control. The bigger, commercial-sized models are the hardest to control and have the most power. They will also cost you the most. For the average yard size, a normal mower will do the trick, whether it is self-propelled or not. It’s best, as we’ve mentioned elsewhere to combine all the necessary factors (money, yard size, length of mowing season, etc) when thinking about any mower purchase.