Octane Question for Newbie!

[7thKing]

This summer I purchased a new 2008 Yamaha VX Deluxe Waverunner (4 stroke). I have had a fabulous summer riding around all of the lakes So Cal has to offer! I have been gassin' her up with 92 octane gas as per instructed from the mechanics at the motorsports shop where I purchased her... The mechanic told me to ONLY use the high octane gas as the others (87 and 89) would be bad for the engine.

My question is do I REALLY need to use 92 octane gas???? I have looked for an answer to this question all over the net to no avail. Can anyone help me with this? Any knowledge on the subject would be GREATLY appreciated!!!

Thanks!

 

[gcboat]

Re: Octane Question for Newbie!

Without getting into all of the compression figures and the rest of that if the mfg. suggests 92 octane - so be it.
I have an 07 Sea Doo with the supercharger - recommended mininum octane is 92. Made the mistake of letting a friend borrow it for a long weekend. Said all he could find was 87 / 89 stuff. The performance was absolutely pitiful until the 92 worked its way through the system.
So, the call is yours. If it were me I'd stay with the big juice. I do !
American white gas only - period.

 

[thumpar]

Re: Octane Question for Newbie!

If it does need the 92 and you put lower in you could have a hole in a piston or other major problems. If it just takes 87 or 89 and you put 92 in your engine is just fine. When in doubt go the safe route, a few cents extra on gas is cheaper than an engine.

 

[Jeff Walkowiak]

Re: Octane Question for Newbie!

Yamaha does not make a 4 stroke engine that requires high octane fuel,, your engine per your owners manual says regular fuel,, since it is set for 87 all you are doing is wasting money and it won't perform any better with the high octane,, so forget what the fool told you as he didn't do you any favor saying to use more expensive fuel,, the timing is set for 87.

 

[7thKing]

Re: Octane Question for Newbie!

Thank you so much for all of your info and insight!

It will definitely help my bank account!