[MarAgt]

The manual for my UForce says to use 93.

I know from experience with ATVs/small engines it's better to run non-ethanol, particularly during periods of inactivity.

My dilemma.  I can get 90 non-ethanol pretty easy, but not 93 non-ethanol.

Question:  Would it be better to run 90 non-ethanol or 93 ethanol with a stabilizer like SeaFoam or StarTron?

I've always been one to follow a manufacturer's recommendation for fuel.  But...

[REDRIDER]

octane rating is more important than ethanol vs non. running lower octane than is required can cause en engine to detonate and cause catastrophic engine damage where as ethanol may cause some extra deposits in the fuel system and may require a fuel filter or cleaning of the fuel system. in pressurized fuel systems like these fuel injected systems it is less of a detriment than in a small engine with a carb with tiny passages. If it is going to sit a while run a star tron or fuel stabil and you should be fine. I run a stabil in my weed wacker, snow blower, and lawn mower and haven't had an issue in 4 years. Now I do not know if they really require 93 octane, seems a little over kill to me and it might have been something lost in translation but I will run 93 to be on the safer side. My sea doo has 11:1 compression and runs 87 octane but it is a hemi type head, I don't think these are hemi type heads so they are more prone to detonation and I think they are above 10:1 ratio so 93 is plausible.

[Sockman]

I don't believe these are high compression engines that are prone to heat detonation - which would require a higher octane fuel.  If I was making the two choices you have, I would go with the 90 octane non-ethanol.  I do agree with Redrider, though.  Ethanol is more problematic in engines with carbs (assuming they are not run consistently).  But, if you can stay away from it, why not.

[MarAgt]

Ah, great info!  Thanks!

[REDRIDER]

they are 10.3:1 ratio which is pretty high, and the book does say to use 93 octane, that is enough for me to use 93 octane for sure. What you do is up to you, my personal opinion, use the 93.

[Sockman]

they are 10.3:1 ratio which is pretty high, and the book does say to use 93 octane, that is enough for me to use 93 octane for sure. What you do is up to you, my personal opinion, use the 93.

I know there's been some discussion about this, but my manual reads "The recommended fuel for this vehicle is 87 or higher unleaded gasoline".

[chuddly]

My experience with more engines than just the CF Moto.....Anything over 11:1 NEEDS at least 93 octane.  More like 100 or 110.  At 10.3:1 the 90 will be just fine.  That is not a really high compression engine. 

[REDRIDER]

they are 10.3:1 ratio which is pretty high, and the book does say to use 93 octane, that is enough for me to use 93 octane for sure. What you do is up to you, my personal opinion, use the 93.

I know there's been some discussion about this, but my manual reads "The recommended fuel for this vehicle is 87 or higher unleaded gasoline".

Which is strange because mine says 93.
actually, I don't know if I have checked my personal manual, the online manual says #93 unleaded fuel. I will double check and see what my personal manual says when I get home

[REDRIDER]

My experience with more engines than just the CF Moto.....Anything over 11:1 NEEDS at least 93 octane.  More like 100 or 110.  At 10.3:1 the 90 will be just fine.  That is not a really high compression engine.

Compression is not the only contributing factor, it has a lot to do with combustion chamber design. A hemi can take more compression without detonation due to no quench area. Saying an engine with 11:1 compression needs 100 or 110 octane but have .7:1 less only needed 90 octane is a huge jump in octane rating with a relatively small jump in compression ratio.  My jet ski is 11:1 compression ratio and only requires 87 octane mon/ron average USA style measurement.  11:1 compression in another engine may require 93 octane different style head, operating temp, timing

[Sockman]

I run 87 per my manual.  I don't hear any pinging, and certainly not any knocking, so it seems spending the extra money on the higher octane stuff would be wasteful (my opinion and my practice).  At the same time, I don't run the machine hard, and rarely (maybe not ever) at WOT. 

[REDRIDER]

I run 87 per my manual.  I don't hear any pinging, and certainly not any knocking, so it seems spending the extra money on the higher octane stuff would be wasteful (my opinion and my practice).  At the same time, I don't run the machine hard, and rarely (maybe not ever) at WOT.

Yea, I'm gonna double check my manual at home. Running higher octane than is needed is wasteful in money and also not good for the engine as you will have more unburnt fuel and carbon deposits.

[doug80638]

From the service manual:

"Fuel type and Octane No. RQ-93 or higher unleaded gasoline"

RQ-93 is not 93 octane in the states. It's 87 octane here.


http://cfmoto-forum.com/general-discussion/why-so-little-hp/msg18790/#msg18790

Further, I asked this specific question of the service dept at the dealer weeks ago and was told that 87 octane was indeed correct, and that ethanol content is not an issue.

[Sockman]

From the service manual:

"Fuel type and Octane No. RQ-93 or higher unleaded gasoline"

RQ-93 is not 93 octane in the states. It's 87 octane here.


http://cfmoto-forum.com/general-discussion/why-so-little-hp/msg18790/#msg18790

Further, I asked this specific question of the service dept at the dealer weeks ago and was told that 87 octane was indeed correct, and that ethanol content is not an issue.

Good to know.  Thanks!

[REDRIDER]

hm, I wonder what RQ stand for it's not one of the normal ways to measure octane, must be a Chinese thing.

[doug80638]

 
From one site:
   
Research Octane Number (RON) is a world wide grading system and RQ-92 does not mean 92 Octane in the U.S.A., Canada, or Brazil which uses a different grading system at the pump, called Anti-Knock Index (AKI) or PON.

I found this at another site:

....USA (AKI/PON) = Europe (RON)

Regular........... 87 = 91
Plus................ 89 = 93
Premium......... 91 = 95
Premium Plus... 93 = 98

So, perhaps 89 octane in the US is more appropriate, though the dealership didn't seem to think so.
A higher octane won't hurt anything regardless.

87 is working fine for me.