Which one would you prefer to push .............................................. the old 2strokes weigh next to nothing. I rekcon they'll be close to 8hp given 5hp 4strokes lawn mowers I've tried.
A quality 4stroke is obviously far far better if you are someone that keeps your grass in good order and only need a "normal" sized hand mower :) (easier starting, quieter, far more fuel efficient).
Actually ... diesel wins ... My ****ty old tractor is the best mower of the lot. It cuts 2.25metres at a time and seems to use less fuel than the 2stroke hand mower!
seeya,
Shane L.

