I recently complained to a Honda mechanic that my Foreman 500 was slow to start in cold weather. It always starts but sometimes with what I think is excessive cranking. I told him I always use 91 octane non-oxy gas. He said that’s the problem. He said going to 87 has solved the problem for their customers. Supposedly it ignites faster.
Has anybody heard about his suggestion or is he blowing smoke up my tailpipe?
The higher the octane, the more resistant the gas is to early detonation (i.e. engine knocking), so it makes sense that 87 is easier to ignite than 91. I have no idea if that’ll translate to easier starting for you, but why not try it for a tank or two?
I know that everyone is big on non-oxy gas, and it still makes no sense to me why you can’t find non-oxy 87 octane gas in MN. Frankly, there is no benefit to running 91 octane if you don’t have a high compression engine.
Check out what your owners manual says. It’ll list the type of gas you should use. Unfortunately, for most of MN though, they don’t make a non-oxy blend in low octanes. It’s a struggle for motors that like 87.
The owners manual says up to 10% ethanol and up to 5% methanol. I wonder if they say that because in many areas non-oxy is not available. They can’t sell equipment if owners can’t buy the fuel they would otherwise recommend.
In any event, a few tanks of 87 is worth a try. Thanks for your thoughts.
The higher the octane, the more resistant the gas is to early detonation (i.e. engine knocking), so it makes sense that 87 is easier to ignite than 91. I have no idea if that’ll translate to easier starting for you, but why not try it for a tank or two?
I know that everyone is big on non-oxy gas, and it still makes no sense to me why you can’t find non-oxy 87 octane gas in MN. Frankly, there is no benefit to running 91 octane if you don’t have a high compression engine.
It astonishes me how few people know exactly what Ralph says here ^^^^. 100% correct.
Try 87 for sure. Cheap fix if it works.
Also, what oil do you run? It may be worth switching to a winter grade oil like 5W30 if you’re running 10W right now. Thinner oil on the cold side of the equation can make cold starts much easier.
Grouse
Coincidence this subject comes up. Had a friend with a new snowmobile have issues with starting and running in -20 degree temps. He asked me about it, and I had never heard of an issue, and I always use 91 octane non-oxy in all of my gas engines. He called a dealer nearby where he was and was told to use 87 octane oxygenated. He did not try while he was there, but when he got back home he called his dealer. His dealer stated they are getting service bulletins on this issue, and the recommendation is to use 87 octane oxygenated fuels, because the engines have been optimized to use that fuel, in snowmobiles, ATV’s and UTV’s. He then drained his snowmobile, drained the carbs, refilled with 87 and has not had a problem since, but has not been in -20 temps yet.
So, it appears it is an issue, and dealers have the same recommendation, 87 oxygenated.
I use 0w40 Amsoil for winter.
I recently was informed of this issue as well. Bought a new Can Am back in December. One of the mechanics gave me a rundown of the machine and maintenance before I took it home. He said the same thing about 87 vs 91 octane when it comes to starting in cold weather. I’ve always understood how octane affects ignition, but it never occurred to me that it would be an issue with starting with the newer EFI engines. They sell Polaris and Can Am and he said this has been a somewhat common theme with both, especially with larger displacement engines. I’ve always run 91 in my off highway engines, only because it’s the only non-oxy fuel I can find. Wish lower octane non-oxy was more available in MN!
I’d rather have a harder starting engine in the cold than a motor that has potential ethanol problems.
No Ethanol for my CanAm ever, no matter how much easier it may start.
I’d rather have a harder starting engine in the cold than a motor that has potential ethanol problems.
Gather your pitchforks, but ethanol gets blamed for far too much. The only problems I’ve ever had involving ethanol are hangovers. 
So is non-oxy fuel the same as ethanol free fuel?
I’ve used nothing but 87 octane in my wheeler for over 20 years and have never had an issue.
So is non-oxy fuel the same as ethanol free fuel?
Yup.If the powers that be chose butanol vs ethanol as an oxygenate,things would be much better.But that’s a whole different subject.
Non-oxy 87 is as rare as hen’s teeth.
<div class=”d4p-bbt-quote-title”>gimruis wrote:</div>
So is non-oxy fuel the same as ethanol free fuel?Yup.If the powers that be chose butanol vs ethanol as an oxygenate,things would be much better.But that’s a whole different subject.
Non-oxy 87 is as rare as hen’s teeth.
Why do people call it non-oxy then? Its labeled as ethanol-free premium at the pump.
Why do people call it non-oxy then? Its labeled as ethanol-free premium at the pump.
Right or wrong, I refer to ethanol-free as non-oxy. My reasoning for running ethanol free in my off-highway engines is equal parts “I believe it can cause problems with fuel systems” and “I believe the ethanol mandate is a boondoggle”. Given the choice, it’s pure petrol for me.
I understand the argument of hard starting over ethanol, as I have had engine problems and carb gumming issues with ethanol. But my friend that saw the service bulletins on this issue, stated that engines may fail to start with 91 octane ethanol free fuels. So not sure you are just dealing with hard starting, it could be no starting. And if you are 10 miles out on Lake of the Woods and it won’t start, not sure I want to be in that situation either.
Why do people call it non-oxy then? Its labeled as ethanol-free premium at the pump.
I believe they used the term “Oxygenated” to sell Ethanol blend in the past. (Or at least sell it to the politicians)
I may be mis-remembering but I believe the metro area Minnoco stations offer an ethanol free 89 octane which might be a compromise?
My Polaris when really cold would crank and crank and finally start. One cold morning I was cranking on it and for sh-ts and giggles grabbed the rope and popped right off. Picked up a new agm battery and started ever since with barely any cranking. I think these newer electronics need more juice to run.
Might be interesting if one of you guys that are having a hard time starting in cold weather. When a no start situation acures, try jumping from a known good battery.
Why do people call it non-oxy then? Its labeled as ethanol-free premium at the pump.
Lots of pumps throughout MN have a sticker that says “non-oxygenated fuel…for offroad, small engine, & collector car use only.”
South Dakota is about the opposite of MN when it comes to gas blend availability. Most pumps have 87 10% ethanol, then either 87 non oxy or 89 non oxy and maybe a 90+ non oxy. If it doesn’t have a sticker listing an ethanol blend percentage, it’s assumed to be non ethanol.
FWIW, we ran 87 octane 10% blend in all of our small engines, lawn mower, honda ATV, and 3010 john deer tractor for 20+ years with no carburetor or fuel delivery issues.
Oh dear Lord in heaven !! you mean that every piston powered airplane in the world wont start and be able to fly in winter time using 100 octane fuel !!!!
and not only that,the majority of them only have anywhere from 5-1/2-1 to 9-1 compression ratios??
dang,someone should of told them that a hundred years ago or they would of fell out of the sky.
ya,so I am being sarcastic a bit,what needs to be understood is this,
its not the fuels ability to ignite at any temperature,its how it is vaporized/atomized,or injected including the timing of said fuel induction and each one of these is very important as well as ignition timing,cranking speed and volumetric efficiency.
when you are spinning over a small cubic inch displacement engine that uses fuel injection,that injector is like a sewer pipe at idle speeds as its meant to deliver a lot of fuel at maximum power,and yes,I know they are pulse width modulated but the fact remains that fuel at low temperatures is not atomized very well,its more like droplets of fuel and they will not ignite readily in this state.
the reason oxygen blends tend to ignite easier is due to the fact that butane,propane and other gaseous fuels are already in a ( vaporized ) state and will ignite easily at low cranking speeds,weak spark,etc especially in small displacement engines,this includes auto engines.
there is a science to this and you must understand it else it gets easy to blame this,that,or the other thing and you dont have a clue to the truth of the matter.
dont blame the octane rating as it has nothing to do with it,it has everything to do with how its administered and in what application.
The Holiday at the Mega stop in Lakeville has 107 octane at the pump. Soooo is that good or bad? BTW – It’s only $7 a gallon 
thats a great price !! down here 117 octane racing fuel is around fifteen bucks a gallon.
now,if you have a three stage supercharged airplane engine that requires 134 minimum octane rating,its almost forty bucks a gallon!!
and yes,that sh!t will light of with a very energetic ability at thirty below zero!!
And,its fired with antique magnetos of all things !!
OK, my head is swimming. Can anyone boil this down into a rational argument or is it hopeless?
OK, my head is swimming. Can anyone boil this down into a rational argument or is it hopeless?
its not hopeless Lynn,in the never ending battle of do gooders to save the planet all engine manufactures must meet a mandate to use renewable fuels which is a joke in and of itself as it takes more energy to create it than it produces.
that said,use whatever they tell,er,uh,ram down your throats to make it start more readily in cold temps,however I will state the following and it comes from many many years of experience of being a mechanic and blending fuels for race engines of many sorts.
unless you use a lot of FRESH ethanol fuels and, YOU TREAT IT PROPERLY DURING STORAGE,I dont care who builds it,ethanol fuels WILL GIVE YOU FITS down the road,I know,I see it day in and day out in my world as I work on this stuff for a living.
there are the guys who say; I have used ethanol since Moses was born and I havent had any problems at all.
if its used daily and I mean every dang day of the week most likely they wont but let that sh!t set for two to three months at a time and guess what??,yep,its brought to folks like me to fix it,no ifs,no ands,and no maybes.
the others who get by using it trade often,dont tell the whole truth,or dont have enough sense to recognize what is causing the problems,or even worse dont realize the engine is not starting as well,performing as it should and run it til it dies and blames the manufacturer for something that didnt last long.
for several years in the owners manual of about every vehicle out there that was E-85 compatible it stated in plain English,every third to fourth tankful of E-85 used,it is recommended that regular fuel is used to maintain proper system functionality.
I know we are not talking E-85 but I mention it because of its effects on the materials used in modern fuel systems.
to put it in layman’s terms,ever get so drunk that you were dried out beyond belief?? ya,ethanol does the same thing to components in your vehicle,toy,etc.
trust me when I say,parts dont lie,and I will throw in as the Famous Grouse says,there are too many snake oils out there and too many folks who dont read directions of said snake oils,,,,,but,its folks that do this crap that keeps me in business.
as much as I would love to help protect you and everyone’s investments if I did that I would be out of a job.
so,what do YOU do at the end of the day?? do what works for you and when you need help if and when something happens,I will be right here to help you out.
Thanks iowaboy. I think I’m going to stay with 91 and put up with slow starting. I don’t trail ride and generally use a tank per month. Snow plowing and running out to my fish house is the major winter use. Ethanol may be more of a hassle if it sits in the tank too long.
Thanks to everyone for the spirited discussion.
All I know is my new Cub Cadet lawn mower started like a bit@# every spring regardless if I treated the fuel or not until I switched to 91 non oxy. No problems any more. So my wheeler and every small engine I have gets it. I run a for Expedition (huge tank) I always fill when it’s about half. Every third time I fill with 91 non oxy so I’m running a blend most of the time. My manual states to run 91 non oxy if towing long distances.
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