2006 50 hp 2 stroke yamaha

[19capehorn]

I just purchased a used 50. Replacing my old 50 Mercury. The tech went through it and mounted it, ran it two different times, both times the motor ran fine, flawlessly. :-) He used his own gas and tank. I get the boat and motor back and proceed to check it out and clean it up. I bought a new plastic tank with yamaha lines and connectors since the boat was rig for Mercury. Ran it on ear muffs in the drive way, fired up and was fine. Took it out and it will not go pass 1100 rpms. :-( Oil level is good, fuel lines are tight. Called the guy and he wants to go back through it but says i should have ran 93 octane instead of 87. Is this correct? is 93 octane the fuel of choice now for yamaha's? Also this is real gas not ehanol stuff. But my 2002, 200 ox66 runs fine on 87 octane as well as my 9.8 yammy. I think i have carb issues here as well as he needs to adjust my shifter rod because reverse grinds in. Thinking about getting my money back and my old mercury and go after a new 50 yamaha 2 stroke before they are all gone. I know long story, my question is ; Do 2006 50 yamaha 2 strokes need 93 octane???? Thanks

[99yam40]

No, 87 is what they are designed for

[rodbolt17]

I take it this "tech" isnt working for a yamaha dealer and does not have yamaha factory training certificates on the wall.
remember 5 star only means the tech has passed a video course and the dealership has watched 3 webinars.

[throrope]

Thinking about getting my money back and my old mercury and go after a new 50 yamaha 2 stroke before they are all gone. I know long story, my question is ; Do 2006 50 yamaha 2 strokes need 93 octane???? Thanks

Higher octane enables higher compression ratios. An often misconception is that premium or 93 octane is better. Not so, High compression engines (i.e. 10:1 or better) will ping, knock or detonate (same thing) if the octane isn't as required by the engine. If your engine is designed for 87 octane or around 9:1 compression ratio, you're wasting money buying premium.

These two stroke engines run less than 6:1 compression ratio. If you need to depend on this guy to make it right, I'd think about getting your money back.

[19capehorn]

Update

I took the boat and motor back figuring on getting my money back. They were ok with that. The head guy looked at the motor and said his helper did not install the new throttle cable right, it had a block on the threads and was upside down restricting it from moving forward. The actual owner of the motor happened by because he saw his motor on my boat, outside of the shop. He stopped by and we spoke, i told him i was returning it. This was before the head mechanic looked at it. He was ok with me returning it and had no problem returning my money. He wanted it back. He changes out his motors every 4 years religiously. He runs his motor every day 20 minutes down a freshwater bayou to his camp, and back at night. The foot looked rough until i cleaned it. But i told both of them they have one more chance, get it 100% and call me. And i will take them for a ride in my boat and see what i think. They need to adjust the shifter so reverse does not grinedddd into gear. Denny the motor owner told me even after if i decide to buy it, if i don't like it for some reason he will take it back. Talk is cheap i know, but they seemed ok with it. No i doubt seriously if Kenny is a 5 star mechanic. But he has been in business 31 years and has a good tract record on record. I am waiting to get it back and will post what i find. Thanks.