Most small engines use Sae 30 or 10w 30.
The generator should have come with an owner's manual that lists the type of oil. Also, the oil refill may list the oil weight to use.
You can burn oil and use the heat to power a generator and you get electricity.
SAE 10W30 synthetic oil.
The best oil you can use in your vehicle is the oil that is recommended by the manufacturer. Use that weight oil and no other way. The brand of oil you use is your choice. Just pick a name brand oil as they are all excellent lubricants.
Honda uses Honda brand oil, made by Exxon Mobil.
You can use any name brand oil in your Honda. I use Pennzoil but that is my choice.
Use exactly the weight recommended by the manufacture of the generator. Any major synthetic brand is what I would recommend on any air cooled engine.
Any major brand it fine. I personally use Pennzoil.
You do not have to use so-called ATV oil. ATV oil is the very same oil as used in your automobile. Use any major brand SAE oil in the correct weight. I recommend you use a 100% synthetic oil.
best oil to use in 7.3 diesel is rotella brand oil
15w 40 Manual at titanindustrial.net
Use any major brand 5W20 oil.