Hi gravelman, I personally have always used 4 stroke engine oil (the same as used in the engine) and found it satisfactory.
The main thing here is as grumpy said, to catch dirt and dust.
A wise old mechanic once told me "The sponge filters and oil are cheap, engines are expensive". So the rule of thumb is to change
both regularly to increase engine life, especially in dusty and dry conditions...(which is most of Australia)
By the way gravelman, a big warm
to the forum. It is good to have you aboard.
