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Discussion Starter #1
Been running ethanol free gas in my quads and lawn tractor for 2 years now religiously. In a hurry to take the kids riding today, I ran to the corner and filled the gas cans with cheap 87 octane gas. My daughters 2008 Sportsman 300 died on the trail and we had to tow it back almost 2 miles. Just did oil change a month ago and new NGK plug. Been running great until I put the cheaper gas in today. Could the cheaper gas be the easy explanation here ?? Tomorrow I’ll siphon it out and never run regular 87 again.
 

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I'm going to say no but its possible. Let us know how you make out.
 

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A friend of mine filled his Harley with cheap gas at the station where he always buys gas and made from there to my shop (about 1/2 mile) - I drained about 1/2 gal of water out of his carb and fuel tank and he was running again. Just so happens a tanker was there filling the underground tanks. Never get gas at any station while the tanks are being filled. There is water on the bottom of the tanks and the pumps are about 2 feet off the bottom of the tank - a pump is typically located near the end of each tank - two pumps per tank - the fill access is in the center - when gas is being dumped in, the water is temporarily displaced away from the center of the tank and can rise above the pump inlet. Those people who get gas at this moment get some or all water mixed with alcohol. A typical car engine with fuel injection can burn this water/alcohol mix in small quantities. The engine suffers a loss of power, fuel mileage and may misfire, but it gets rid of it. A small engine with a carb will simply die (even a Harley is a small engine) and the water has to be removed to restore function.

Now your problem may be totally unrelated to water in the fuel, but it has to be considered.

Alcohol is hygroscopic and will absorb water from the air - it only takes .4% water mixed with alcohol to get the alcohol to separate from gasoline which is hygrophobic. The water on the bottom of an underground fuel tank is a mixture of water and alcohol. Every so often, a gas station has to have the water pumped out of the tank. There is a putty that is applied to the measuring stick for measuring the amount of gas in the tank (so many inches of gas = x number of gallons based on the size of the tank) - when the putty contacts water, it changes color and the station manager knows ho much water in in the tank. When the water is getting close to the pumps, it has to be removed.

Now water mixed with alcohol will seemingly burn. Pour a mixture of water and alcohol onto hot concrete and it can be ignited with a flame. Alcohol has a lower boiling point than water and will evaporate out of the water at a higher rate than the water evaporates. During this evaporation state, the water can be ignited. When the flame goes out all that is left behind is the water.

You may find that getting the fuel and the dying of the engine was purely coincidence. One time while traveling with friends, the guy in the lead pulled over for fuel - he pulled into a cut rate station to fuel up - I protested that he didn't pull into the Standard Station right across the street and he said he always filled with cheap gas - it was our habit to fill all the bikes from one pump and pay en-mass - the lead rider always determined when and where to fuel and we took turns leading. A short time after gassing up, my bike started to misfire - I blamed the fuel - at our next fill up, I chose an Ammco Station and filled with Ultimate (no alcohol), but the engine continued to misfire. When we stopped for the night, I drained the carbs to purge water if there was any. The next day the misfire continued and got worse - when we stopped under an overpass on the Interstate to let a summer storm pass, I changed the spark plugs (I always carry certain spare parts and tools - tire plugger, spark plugs, coolant, oil, clutch cable and jumper cables) - low and behold, after changing the spark plugs the misfire was gone. It may have just been a coincidence the plugs started misfiring after filling at the cut rate station or it may have been something in the fuel that started the misfiring, but changing the spark plugs remedied the problem.

Let us know what the diagnosis is.
 

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Discussion Starter #6
Follow up from a few days ago. Can only assume my Sportsman 300 had a bad reaction to the cheap 87 octane gas that day. Drained the tank and refilled with the ethanol-free stuff I normally use. Little sea foam also. Absolutely no problems since that one day I put cheap gas in it.
Happy Riding Everybody!!
 

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WOW, glad you got it fixed up!!
 
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