A few years back we bought a new Suzuki 15 in Fiji
. The motor
was American market bound, and was marked for 100:1 oil mix. The dealer said that Suzuki had to do that in order to meet some regulations
in the States, but that the motor
had been designed with 50:1 in mind, and he recommended that we use that ratio. No harm came from it, and when the motor was stolen 12 years later, with many many hours of hard use and very little maintenance
it was running fine.
I've continued to use a bit extra (around 75:1, but not carefully measured) on the Yamaha 15 we replaced it with, and which apparently is really designed for 100:1. Smokes a little on cold startup, but runs fine, doesn't foul plugs and is now 6 years old. Certainly doesn't seem to impede anything, and just might help!
Jim and Ann s/v Insatiable II lying Manly Qld Oz