What Gas Octane Rating For Mower ?

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While I've used 87 octane rated gas (treated afterwards with ethanol remover) ) in my lawn mowers - I wonder if there is a benefit to moving up to 89 or 91 octane rated gas for my Honda ?
 
Doubt it ... it won't cut grass any faster with 91.
 
i tried higher octane one time a few years ago...ran 10 gallons worth thru my push mower and the rider ...I didn't notice any difference so why spend the extra $$
 
Waste of resources
smile.gif


Lawnmover wont notice...I would use 100 octane (RON) only in a high revolving 2T OPE equipement (ie huskvarna 550xp chainsaw & equivalents)
 
Most of our E0 in the area is in 91 octane and is generally what everyone uses. I only run VPracing C9 in strokes everything gets same ratio. No clue what ethanol remover is or how that works. No E0 in the area??
 
Originally Posted by ChrisD46
While I've used 87 octane rated gas (treated afterwards with ethanol remover) ) in my lawn mowers - I wonder if there is a benefit to moving up to 89 or 91 octane rated gas for my Honda ?

Instead of increasing your octane, I would use an ethanol free gas which the farm places sell.
 
Small air cooled lawnmower engines have such a low compression ratio that they will run good on 81 octane gas, if you could buy it.
87 octane gas will work fine. Higher octane than this would be a waste of money, but E0 would be preferable to E10 if it is readily available in your area..
 
If the 87 is a bad batch sometimes I would get some 93.
But Most mowers are VERY low compression and don't require high octane.

I am not familiar with the Kawi twins - or similar - on riders.

Most of these engines are low specific output, mid rpm, so I wouldn't expect anything over 9:1.

But I haven't researched it, so IDK !
 
I usually fill my can with 93, but Im sure after 6-8 months its degrades to regular since I dont go through it so much. They were built for regular, you should have no problems besides any ethanol in there.
 
Originally Posted by wag123
Small air cooled lawnmower engines have such a low compression ratio that they will run good on 81 octane gas, if you could buy it.
87 octane gas will work fine. Higher octane than this would be a waste of money, but E0 would be preferable to E10 if it is readily available in your area..


My old briggs flathead recommended 77 octane or better. But my chonda wants 87, per manuals.

I ran my briggs on "white gas" when gas was $4/gallon-- I got the can at a yard sale. It ran fine, exhaust smelled funny, but if I put more gas than I needed in it would evaporate out over the following week!
 
Why would you question this? If it runs fine on the cheaper low octane you already use, then you wasted every moment thinking about it.
 
Originally Posted by atikovi
What does your owners manual say (canned bitog reply)?

That is probably the best advise BITOG has to offer on many of the type of questions.
 
All my 2-cycle equipment recommends 89 octane for some reason. Therefore I just fill my jugs up with 89 so I'm not having to use separate gas for different equipment.
 
Originally Posted by 92saturnsl2
All my 2-cycle equipment recommends 89 octane for some reason. Therefore I just fill my jugs up with 89 so I'm not having to use separate gas for different equipment.

^^^ Echo and Stihl recommend 89 octane in their 2 stroke equipment per their owners manuals.
 
All of my lawn tools recommend using zero ethanol fuel. That is for my 4 cycle and 2 cycle tools. One of the tools came recommended to use 91 octane. So all of them get 91 non-ethanol fuel. That includes my Honda mower. Have not had any problems doing that for quite a few years now. Just costs a bit more for the summer stock of fuel but it isn't really that big a deal. Maybe a dollar more of cost going into the 5 gal. gas can.
 
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