Oil mixture for 25 hp Yamaha

[Deadmeat]

I bought a new 25 hp Yamaha 2-stroke motor recently and am now about at the end of the break-in period. The first 10 hours are to be run at a 50:1 oil mixture and after that the owner's manual says to run it at 100:1. As much as I know the Yamaha folks built this thing and should know what they're talking about, my feeling has always been to run a heavier oil mixture than recommended. I did this in an old 1988 Evinrude for many years and never fouled a spark plug or had problems with carbonization. I don't want to keep running it at a 50:1 mixture but I'm not sure what ratio I want to run it at. Has anybody out there got any suggestions?

 

[bAcKpAiN]

Especially for a new motor, I would follow manufacturer's specs. It will certainly come in handy if you ever need to make a warranty claim.

 

[Quackrstackr]

Agreed.

I would do what the manual says. No sense in burning double the oil if the manufacturer says it will be fine otherwise.