Champion Generator

Colo Native wrote:
Just wondering what anybody used to have a load on for the break in? 50% or less.

Not sure where you got the 50% or less for break in, but this is sure to open a can of opinions.

MY opinion, after spending many years rebuilding motorcycle single cylinder engines is to run it hard to get it hot, shut it down overnight to cool, then repeat for 3 or 4 cycles; hard, cold, hard, cold. The idea is that the relatively soft metal of the piston rings are designed to wear into the cylinder; the proverbial "break in". Running a motor without enough load to get things hot will result in the rings never really breaking in and the motor burning oil as the oil from the lower crank is not sealed from the combustion chamber plus the fuel from the combustion chamber seeping past the rings into the crank and diluting the oil.
The other opinion on break in procedure is to vary the load. Many car manufacturers tell owners to vary speed, not use cruise control, etc during the first few hundred/thousand miles. For a genny, I think this would be easier to apply than running hard and cycling hot/cold for break in.
For my most recent generator, a Honda 1000i inverter generator, I used my smoker without anything in it. The smoker is electric and cycles on and off every 5 to 20 seconds without any mass in there to stabilize the air temperature. The heater element draws 750 watts, so call it 75% of the genny's capacity. I ran it for about an hour like that on ECO setting. The motor changed from idle to near full RPM's several times a minute as the load would cycle on and off with the smoker. I now consider it broke in. Other loads that you can use to cycle might be small space heaters with low/high settings. Most have a low of 750Watts and a high of 1500 watts. Add/Subtract heaters as need based on the rated output of the genny being broke in.