There are options that are more robust for small engine use than standard passenger car oil.
Heavy duty engine oil like Rotella or Delo, these are usually available in 10w30, 5w40 or 15w40.
Small engine oils like Honda, Briggs or Kohler oils are actually formulated very similar to the Heavy Duty engine oil but much more expensive. You can get a gallon jug of Rotella 10w30 at Walmart for about $12. The small engine oils can bee $7 or $8 per quart.
What I run in my Champ is Amsoil 10w30 small engine formula, full synthetic and takes the heat very well. I think I ran Rotella 10w30 during break in.