any tips on modifying a 25hp Yamaha outboard? Wanna boar it out to a 30 or 35.
Sell the 25hp and buy a 30 or 35hp. Not worth the hassle, especially if it's a newer style efi computer managed engine.
Maybe go 40hp then you can even back it off abit and still be fangin it
If it's a 4 stroke. Even going to a 2 stroke would be faster.