| 25:1 tends can be a little smokey espically in the running in period as the engine is not being used at full power & tend to load up a little & put out more smoke
a good NGK plug will help if you dont already have one & once run in try less oil 32:1 is fine some run leaner on oil but i wouldn't advise going too lean on the oil ratio as less oil can create more heat & excessive wear etc... | 
