No oil consumption. Years ago I had a lot of misfiring problems. After talking with local dealer, changing plugs, etc., I ended up replacing both coils thinking it was low voltage. Come to find out I had a much simpler fix that I only figured out on accident. For years I had been washing and replacing the foam filter which covered the expensive paper element filter. The paper looked fine so I kept on using it and just washing and re-oiling the foam filter.
Well, guess what? All my problems were fixed when I replaced the paper filter with a new one. It had gotten clogged with dirt that could not be seen with the naked eye. The clogged paper filter had been restricting air flow causing misfiring. Now I change both air filters every two years along with my gas filter and spark plugs. And only with Honda OEM.
By the way, this is the GXV 620, V Twin, 20 HP Honda engine.