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I cannot find the gl650's fuel requirement anywhere in my books. Can someone tell me what octane it should be?
 

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I just run regular unleaded in mine. Shouldn't need anything beyond that.
 

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87 is your fuel. Technically the bike should run fine on 85 but not that e85 crap. That will probably destroy your engine. So stick to 87. It's a safe number you won't confuse.
 

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These bikes will run on that Ethanol blended crap (in some states you have no option) but expect to clean your carbs more often unless you're a very regular rider. If I were stuck with it I'd keep a bottle of that Stabil for Ethanol gasoline around.



The crap burns differently and due to the alcohol content it has an affinity for water - literally sucks it out of the air.



Doesn't affect the newer cars as much as the fuel systems are sealed and the modern computer controlled engines help to adjust for the different burning characteristics. At least that's the bullspit they're trying to fed us, my 1996 is computer controlled and I lose at least 5% mpg if I get stuck with it, my check engine light tends to come on intermittently too.
 

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I'm with Marshall on this.Even though we have a different blend of fuel over here and I use just straight economy brand unleaded I still add a bit of any cheap fuel treatment from the supermarket.



Don't pay premium prices for Brand names as it's all pretty much the same UCL(Upper Cylinder Lubricant) no matter what the sales hype says.It also helps keep the carbs clean/lubed and also as per above stabilizes the fuel if you have to leave the bike unused for any length of time.



My 10 penn'th.
 

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Discussion Starter · #6 ·
Thanks guys that's what I needed to hear.
 

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87 is your fuel. Technically the bike should run fine on 85 but not that e85 crap. That will probably destroy your engine. So stick to 87. It's a safe number you won't confuse.




Please note Don is talking about 2 very different numbers here, 87, 85 is octane rating, While E85, the 85 represents the percentage of Ethanol in the fuel, 85% ethanol, 15% gasoline.



I would not recommend E85, the rubber in our carbs was not designed for it. E10 is very common (hard to buy fuel without ethanol now 'round here) and will be fine.



As for performance, you won't get a bump from running 92 or higher octane. higher octane has a higher resistance to pre-detonation, the fuel itself doesn't contain more energy than the lower octane fuels.



Vehicles of course designed to run on it will have an advantage, as they require higher octane due to higher compression, the hi compression giving the performance gain, not the fuel.



Modern vehicles with knock sensors designed for 92 or higher fuel will run normally on 87, but performance will be reduced due to the computer adjusting the timing. One of my cages has a big 24v V6 in it, 250 hp. Running 87 just fine, but I can feel a performance difference, and the mileage is worse. More expensive mid-grade fuel pays for itself with every tank with improved mileage.
 

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The info plate on the right side of my frame (by side cover) states to use 91 octane min. I will not put alcohol contained gas in my bike or any of my small engines. I think the non-oxy I buy is 91. If they sold it in 87 I'd try it. I do much with old outboards and that alcohol stuff raises holy hell with the carbs and the tanks get nasty too. Probably from the extended non-use. For me it is simply not worth using.
 

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The info plate on the right side of my frame (by side cover) states to use 91 octane min. I will not put alcohol contained gas in my bike or any of my small engines. I think the non-oxy I buy is 91. If they sold it in 87 I'd try it. I do much with old outboards and that alcohol stuff raises holy hell with the carbs and the tanks get nasty too. Probably from the extended non-use. For me it is simply not worth using.




That's 91 RON which is about the same as 87 in the US.
 

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Exactly right.


Here3 in the U.S. they post an average of RON + MON figured exactly as (RON + MON)/2



More than half our gasoline sold is E10 which means up to 10% ethanol and, unless your car is mid 2000s or newer, it will usually disagree with a few things that the newer computers can adjust for.



In scientific testing terms ethanol has a higher octane rating than gasoline



In scientific testing terms ethanol has a lower energy content than gasoline



They can legally take a lower than 87 octane gasoline and mix it with 10% ethanol to raise the advertised octane number. A lot of the mid-grade and premium gasoline sold is little more than regular with the ethanol factor added in.



Even 100% gasoline varies widely by the refinery that made it and what base oil stock was used. We have a few stations that have absolutely outstanding 100% gasoline and a few whose gasoline sucks even at 100% pure.



Crude oil is classified as sweet or sour, you'll have to look up the difference.

Gasoline made from sour crude is usually sub-par even on an equal octane and no ethanol comparison.

Gasoline made from the best crude oil stock tends to be the best, their 87 octane may not knock where others will.



Sub par gasoline usually smells odd. It smells old. it smells like it has some diesel fuel in it or just smells funny.

(yes, adding diesel fuel to gasoline somewhat increases the rated octane properties but only a few percent can be added)

Good gasoline smells clean, crisp and volatile. You'll notice strong hints towards a decent concentrate of toluene &/or xylene in it.

The more it leans towards the xylene smell the better it seems to be but the toluene stuff isn't far behind.



Truth of the matter is I've got one station that consistently provides excellent gasoline and I try to fill up there as often as possible. It generally costs a little more but the returns in mpg and driveability are well worth it.



If I'm stuck close to empty and have to buy gas I've got a few alternates I'll settle for and one of those is even an E10 gasoline, it must start out with good base stock before they throw the vodka in it. Oddly enough, at any station including the ones I know are historically acceptable, I'll pump a small amount then intentionally get some on my finger to smell it. If it doesn't smell clean, crisp and volatile I'll just pump enough to get down the road.



I didn't used to be so critical until I built up that 98 GTP Pace Car and had the tuning optimized for 95 octane but would still accept a good 91. This was actually a car that, if you goofed and ut 87 in it, you babied the thing over to one of the few stations we've got that sells racing gasoline in 107 unleaded and (if you bring a can) 114 leaded.



It's also true that running a higher octane gas than your engine needs gains you nothing but perhaps a bit more detergent additives.



Our bikes were built during the days when "regular" pump gas was usually 87 - 89 octane - at least over here.
 

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In my area we've had 10% ethanol added to gas since the late 70s, there has been no choice in my area for over 30 years. I remember seeing the little corn stickers on the gas pumps and the drama of how it was going to plug our fuel systems with a crystallized syrup, eat fuel lines, kill fuel pumps, rot out gas tanks and destroy engines. Our cars fuel economy and HP would drop in half!




I've never had any issues with my vehicles including a 1962 Olds with a 394 Ultra High Compression Rocket, air cooled Corvair, air cooled motorcycles, CX500C, turbo charged CXs, two snowmobiles (2 stroke), L82 Corvette and a 1.3 liter Busa engine that cranks out 175 HP.

Riding mower, chain saw, leaf blower, weed eater and snowblower are seasonal items that get parked and forgotten with whatever gas is left in them and they always start up fine 6 months to a year later. And NO I don't use Sta-bil or anything like it.

My generator is used only for power outages and the gas in it is always over 1 year old and I've never had an issue with starting it.

My Corvette Stingray was put away for the winter in Nov. of 2007 and I didn't take it back out until July of this year. It started right up and I drove it around gently until that tank was used up.

I also tend to keep vehicles for a very long time and some are used very little which is supposedly horrible when it comes to 10% ethanol gas. I bought my FI Geo Storm when I was 19 (I'm currently 40) and it has 60K miles on it...never touched the fuel system. My 99 Sunfire was also bought new, has 35K miles and the fuel system has never been touched. Last month I sold the 88 Toyota truck which was in the family since new and at 22 years old the FI system still worked flawlessly. Only repair to the fuel system was the cleaning of the cold start injector at 20 years old. It still had the factory fuel filter as do most of my vehicles.



As far as cleaning carburetors...not had to deal with that much. I did have to clean the carb on the Honda scooter before selling it due to hard starting. Was it due to 10% ethanol or simply because it was almost 25 years old and used very little? I can't even recall having to touch a carburetor on my small engine yard equipment. The carbs on my '79 CX500C NEVER had to be worked on or cleaned...it was 11 years old when I bought it and I owned it for 14 years. And unlike many people in this forum I've never had a gas tank rot out and leak in a motorcycle and I've never had to clean or seal a tank due to flaking rust.



When it comes to buying gas I have no favorites, just pull into any franchise gas station. The turbos would be the only exception as our premium is either 92 or 93 and I prefer to use 93 in them.



This topic was discussed in detail on the old board and I know I'm not just lucky when it comes to 10% ethanol as others have also had absolutely no issues with it.
 

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I usually split the difference and pump in 89 octane in the Honda, usually premium or 89 in the Ural. All gas in my region of Illinois has had 10% ethanol for longer than I can remember, easily many decades now. Works just fine for me. I do add a little bit of SeaFoam now and then when I think of it.
 

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Anyone ever notice that "mandated" often has a lot to do with what your main grain crops are?
 

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George, compared to the fuel available to me I will say that you have been extremely lucky with the fuel you use in rec and utility engines. I too have (had) numerous vehilcles and small engines and until switching to non alc fuel for my small engines I suffered with sour tanks and crap filled carb bowls regularly.

I can say I have never had trouble with the fuel systems of any of my cars or pickups using the gasohol like you. I guess that is because the fuel is regularly renewed.

I have noticed several folks on this site have commented that all that is available where they live is the gasohol fuel. In Duluth, 4 of the 6 stations I frequent for fuel sell both types. This has me thinking. Could the fuel available to me be that different than what is available to you and those of you that have never had any adverse issues using gasohol or having gasohol spoil even when not using a stabilizer?



I was told that there are only a few refineries in this country. I don't know if that is true. I know I live very close to one in Superior Wi. I have always assumed my gas came from there and would have to be a fresh as any available anywhere. Maybe it doesn't come from there. Or maybe they do less with it since it is being bought more qucikly.

I do not doubt you or anyone else that have no problems using the stuff. I am saying that for me here in Duluth that stuff gets bad within the time between seasons and prior to me switching to non-oxy I pulled more carbs and dumped more cans then I care to count.



A couple years ago a pilot friend of mine showed me his fuel alcohol testing kit. I was so impressed I bought one. I found that the stated 10% stuff I bought varied from around 5% to nearly 15% at the pumps I frequent. I also found occasionally I'd even get a % or 2 in my non-oxy. I was told that the % in the non-oxy was due to residual in the line from the shared pump. Do any of you perform this testing? I'd be curious if 10% in Indiana is more like 5% or something. WIth the cost of corn these days I'd guess the oil companies would put less alcohol in their mix. I don't know and am not a fuel expert just relying on my experience and hope to learn more about this. I can say that I would much rather pay the 30+cents less per gallon for the oxygenated fuel.
 

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There are refineries in Whiting Indiana but I'm not sure if our fuel comes from there or not. In Lake, Porter and LaPort counties we have emission testing on cars and the pumps have flaps on the nozzles. About 5 years ago I noticed a huge difference in the smell of our gasoline, one day it just had a repugnant stench.

Now if I drive 20 miles south into Jasper county the fuel smells like it used to plus they have old fashioned pump nozzles and no emission testing.

I have no doubt they change fuels for different locations but how much is hard to say.
 

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The federal mandate of 10% ethanol sucks major ass. Once that started happening here I had to up the jetting in my car's carb 1 size, as well as replace all the normal 30r7 fuel line with the more robust 30r9 fuel injection hose. The added ethanol was slowly eating away the inside of the 30r7 line, the clear fuel filter in my car was turning a blackish color after the first 6 months or so.



My parents live across the city, and this summer I went over there and my dad showed me his 10 year old riding lawnmower all of a sudden running rough. This thing is well maintained and always parked in a shed. After digging deep, I discovered the carb fouled with a black paste, looked like fuel line residue that had eventually gotten past the filter. Pulled the 1/4" 30r7 fuel line, cut it lengthwise, nasty decayed...ran my finger down the line and it was like black paste. Replaced that line with 30r9, cleaned-out the carb, and it runs good again, but still a little lean.



Thank you ethanol. Rant over.
 

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The corn farmers are making a bit more money but we're paying a ton more for groceries - almost everything has something to do with the price of corn associated with it, a lot more than you'd imagine.



The one saving factor for a few places are that ethanol has to be trucked in, can't be run through the transport pipes - yet. Why not? Because it will eat them up.
 

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Good posts, marshallf3. Yes, I pretty much hate ethanol in gasoline too. You should see the dance the aviation people have to go through if they want to run mogas in their airplanes. Lots of older general aviation engines were designed for 80 and even 65 octane fuel, which can't be found at airports anymore. So they're stuck buying 100LL (100 RON Low Lead - high lead fouled plugs) at $3.20+ per gallon.



There are changes that then allow the use of mogas, but there have been a lot of problems with ethanol content in the fuel - tank sealers and fuel lines don't respond well to it, and many airplanes seem especially good at getting atmospheric moisture into the fuel tank. The water then attaches to the ethanol in the gasoline and settles to the bottom of the tank where the fuel pickup is. Badness follows shortly thereafter.



I always wondered if the banning of MTBE and ETBE in gasoline didn't have a lot more to do with them not coming from corn fields than with any possible toxicity, especially given that an engine running rich on ethanol makes lots of formaldehyde and acetaldeyhide, which aren't things you ever want to breathe either...
 
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