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What gas U been useing for a 650?

8K views 25 replies 15 participants last post by  Sick Mick 
#1 ·
Book says you can use just Reguarl. But I thinking Plus or Prem .might make bike run better.Useing Reg gas now seem to run alright.
 
#2 ·
Higher octane = more anti-knock additives. If it ain't knocking on regular, you don't need premium.

But don't take my word for it: try a tank of the premium stuff back-to-back with regular 87. If you weren't noticing any knocking or pinging on regular, you won't notice any improvement with premium.

A lot of the gas companies try to imply in their ads that premium is somehow better or packs more power than regular. It's advertising hype.
 
#7 ·
The compression on the 650 is pretty low so there should be no need to run anything higher than regular and the owners manual would tend to agree.

A very common misconception is that high octane fuel is more powerful, it is not. It is actually harder to detonate, thus allowing higher cylinder temps before pre-ignition becomes a problem. If your vehicle can run full timing advance at a given octane rating with no detonation, increasing the octane further will actually cost you power and economy. That's the theory anyway, I have recently decided to put it to the test. I keep very close records of my fuel economy and have tons of data on the kind of mileage I get with regular. I figured I'd run premium for a while and see what happens. I fully well expect to only gain a lighter wallet, but this sort of thing interests me so I'd like to back up theory with my own data.

As some others have mentioned, ethanol blended fuels can be a big problem. Most vehicles will run just fine on e10 but the stuff degrades VERY quickly and can cause serious damage to your fuel system if allowed to phase separate. Thus you need to examine your riding habits. During the summer I ride my bike as much as possible and burn mostly e10 gas. The reason being that there is only one station in my town that sells pure gas and it is usually $0.30 per gallon or more higher than e10. Over the summer it is rare that gas will be in my tank for more than a week, so I don't worry about it too much.

Now fall and winter is a different story. Weather patterns are so stupid here that it can easily go from perfectly comfortable to ride to parking the bike for the winter in just a matter of days. As such when the weather starts to get colder and I might have to park the bike for an extended period at any moment, I start to fill up with ethanol free fuel and I go the extra step of treating that with Amsoil fuel stabilizer. I make it a point to do this for several tanks before I have to park it just to get the most ethanol out of the tank as possible. Consider this, it's a 4.2 gallon tank. If it has 10% ethanol and your fill-up is only 3.2 gallons of 100% pure gasoline, you still have 2.3% ethanol in your tank. Do it again and you are finally under 1%. Is this overkill? Probably, but if you've ever dealt with ethanol related fuel problems, you'll understand why I do it.
 
#8 ·
LBB, when I had my 650 classic, I used ethanol free 87 octane and it ran great. Like eruby, I have the pure gas app and it helps a lot when I'm out of town on my 950t. Running premium in my 650 only cost me more at the pump. When I traded it in, I was getting a consistent 55-58 mpg on the highway.
 
#10 ·
A lot of good info,think ill stay with Reg, gas and just before laying her up for the winter will run some ethanol free gas and run the carbs dry.Filling her up about once a week so far going to work and back...
 
#12 ·
I agree with eGo. Add a good stabilizer and leave the fuel in there. Not only does it keep everything moist and working but it keeps anything else that isn't supposed to be in there out, ie, bugs spiders etc. That may not be a big risk but it just something I have always feared. Torn apart too many old mowers and such and found all kinds of stuff living in them!
Plus even if you run the carbs dry, the bowls still have fuel in them.
 
#15 ·
I would go with the guys that say ethanol free . For where I am that means premium . I run a number of small engines on the farm and I've been having carb troubles the last few years . Taking things in every couple weeks to have the carbs replaced or a kit put in gets expensive . I thought my repair guy was doing a number on me and went to another shop . 1st question what gas are you using? I've swithched to non-ethanol no problems . Same thing in a friends car shop . There are parts that don't like the ethanol . For the 40 cents a gallon more I'll run premium .
 
#18 ·
I would go with the guys that say ethanol free . For where I am that means premium.
That's really odd. In my town there is exactly one pump that has ethanol free in all grades. Most other towns I have been that have ethanol free it is a separate pump and it is usually only available in 87 octane. I guess the idea being that most people who want it need it for small engines that don't usually run super high compression.

Summer said:
In my experience and talking with other folks the real issue with ethanol is when it sits for long periods. In a container the alcohol will absorb moisture and also separate from the gas(or so I have heard don't know for sure). When left in the fuel system for long periods the alcohol eats away at the rubber seals and such as they were not designed for use with alcohol.
As long as it's fresh fuel and you are riding is every couple weeks at least, I wouldn't think you would see any issues with it.
Exactly. Ethanol is just fine so long as you burn it, but if it sits for a while it can cause problems and I have seen them first hand.

Last year my brother had a large oak tree taken down in his front yard and left the log so I could cut it up for firewood. I knew there was going to be a lot of cutting but I know my saw is fairly fuel efficient so I knew I would not burn all of the gas if I mixed it in my 2.5 gallon can. With this in mind I put two stroke oil and fuel stabilizer in my empty can and then filled it up with ethanol free gasoline. My father also mixed up fresh gas for his saws but he used regular old ethanol gas and no fuel stabilizer. Both of our saws ran great at the time and after several days were placed in storage.

About 8 months later my father and I needed to tackle another tree. Neither of us had touched our saws since we had last used them. My dad's saw is a little more powerful than mine so he decided to start with it. It took forever for him to get it started, and when he finally did, it didn't want to idle and it was seriously down on power in a cut. I pulled out my saw and it started on the second pull. It also idled perfectly and was in no way lacking power.

I knew immediately that ethanol was the problem and I told my dad as much. We ran out the fuel that was in it and tried some of my stabilized pure gasoline. It was a little better but it certainly wasn't right. He worked with all the adjustments and even tried running some Seafoam through it. He got it to idle but it was still down on power. Eventually we just gave up and used my saw.

Some time later my dad and I were at a Husqvarna dealership buying a new lawnmower and I just asked the guy "what would make a model 44 lose power during a cut?" Without hesitation at all he said "gunk in the carb from ethanol gas."
 
#16 ·
At least you have that option....most of us don't.

However with that said....I've used regular 10% ethanol since I got my bike 8 years ago and have had no carb issues because of fuel....or anything else.

Give these Mikuni's a little love and they'll go forever...
 
#17 ·
In my experience and talking with other folks the real issue with ethanol is when it sits for long periods. In a container the alcohol will absorb moisture and also separate from the gas(or so I have heard don't know for sure). When left in the fuel system for long periods the alcohol eats away at the rubber seals and such as they were not designed for use with alcohol.
As long as it's fresh fuel and you are riding is every couple weeks at least, I wouldn't think you would see any issues with it.
 
#19 ·
Stihl now sells premixed gas in bottles at the store. I was told by my local dealer that if you purchased a new product and did not buy a bottle of their gas with the purchase they would not warranty the product.
 
#22 ·
I have had my 2011 650 custom for 3 years now and I can tell you from experience that you don't need anything more than regular. I have tried mid grade for a while and 93 for a while. The bike don't run any better with higher octane but the engine will get hotter than it should. There was no difference in power or fuel mileage. During the winter and hurricane season I will run ethanol free fuel but other than that its regular all the way. J/S
 
#24 ·
I too have tried 89,91,93 octane gas and saw no difference in the way my bike runs. Hard to tell on engine heat though.

87 octane regular seems to be the best to use. After all the bike was engineered to run well on this grade of fuel.

If your bike is stock or has some upgrades like exhaust and intake mods
it should make no difference that you run 87 regular gas in the tank.:D
 
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