I would definately go with Brison's recommendation for the simple fact that they are the ones who have to back up the warranty. I figure if I follow their recommended ratio and the engine is damaged, Brison is on the hook for the repair. If I go outside their recommendation and the engine gets gummed up, then I have to fight with an oil manufacturer to get my engine fixed. I just dug out my manual and mine doesn't say anything about using the ratio written on the bottle of oil. The bottle of Klotz I have says to use 40:1. I went with Brison's recommendation and use 80:1 since they specifically say to use a good synthetic such as Amsoil or Klotz at that ratio.

With my other gas engines (weed wacker and chain saw) I don't see any difference in the smoke with too much oil, but I definately see a difference in how they run![:'(]