First comment: why does it matter. These are very reliable engines.
Second comment: There are three different levels of Honda OPE engines. The lowest level is the GC-X series. The upper two are GS-X and GV-X. Which engine are we talking about?
Okay - keep in mind that the GC engines have an aluminum bore whereas the GS and GX engines have a cast iron sleeve. I think one could expect to see more aluminum in the former vs. more iron in the latter.
Okay - keep in mind that the GC engines have an aluminum bore whereas the GS and GX engines have a cast iron sleeve. I think one could expect to see more aluminum in the former vs. more iron in the latter.
In a small engine any synth. oil of the recommended weight changed regularly will more than suffice.
The rest of the machine's equipment will likely fall apart first.