Dave Butler wrote:

Why "especially with all the accessories installed"?

The injection system tends to be more complex and heavier than gasoline models or
carburettors. This is because the injectors spray fuel directly into the cylinder
rather than into a section of the intake manifold. Many diesels handle the higher
CHTs by using water cooling systems, and those add weight (Lycoming was working on
one of these a few years ago). On the other hand, the glow plug systems used for
starting tend to be lighter than the magnetos used in gas engines.

The main cause of the weight difference is still the fact that everything must be
beefed up to handle the higher compression, though.

Why is a 2-stroke cycle engine lighter than a 4-stroke?

There are twice as many power pulses per minute with a 2-stroke. They usually are not
as efficient as a 4-stroke, so you don't get twice as much power, but they will
easily produce 1.6 times the power of a 4-stroke the same size, and most do better
than that. So a 200hp 2-stroke engine is smaller than a 200hp 4-stroke engine. In
addition, 2-strokes don't have a valve train, which saves some weight.

George Patterson
In Idaho, tossing a rattlesnake into a crowded room is felony assault.
In Tennessee, it's evangelism.