What's a " perfect " single outboard for a 23' Sceptre ?

[Bushwacker]

That knock sensor is a neat feature because it can detect a lean misfire/detonation situation that can kill any motor! Fuel starvation/lean operation is a significant problem with E-10 gas because the extra oxygen in the fuel causes it to burn very hot and can cause piston/cylinder wall scuffing. I asked the wizards on the E-Tec owners forum if BRP had considered using an oxygen sensor in the exhaust to detect lean operation, ala Yamaha HPDI. The reply was that BRP did consider that, but O2 sensors are a PITA from a reliability/maintenance standpoint, and that knock sensors would do the same thing but more reliably.

[shine]

make a spreadsheet that will give you a cost per hour to operate which will be different for each engine and different at each RPM. Use fuel (what kind you need), maintenance, oil, etc. Then input the burn per hour at different RPMs (running, trolling, idle), then you can make a "typical day" that will include the cost for the different uses. For me the numbers pointed to 4 stroke over 2, even after for account for the higher maintenance cost.

For 2 stroke, I used 90 octane ethanol free. For 4 stoke I used 89 octane pump gas. If I rand more than 150 hours of typical fishing, the 4 stroke paid off quickly.