Ethanol & octane

goldminer MT

New member
Joined
Dec 23, 2010
Messages
8
Location
Sapphire Mountains Montana
There's a Quick Stop up the road selling fuel for "sleds" only, 93 octane & no ethanol. $3.33/gal
I tried some & now my sled won't idle,loads up & basically runs like crap.
What's up? Is this fuel only for the new 4 strokes or what?
Should I siphon my tanks?
 
more octane makes a sled richer,without changing the jets.

if your sled was jetted for use with ethanol fuel and the jets were increased for safety, going to a real 93 octane fuel will for sure make the sled richer. You could simply try and cut the gas in the tank with some lower grade gas and see if it cleans up.
 
From what i understand (I am not an expert on the subject) is that octane controls the combustion to prevent premature detonation. When you use cheap gas with lower octane with a higher compression, the additional heat and compression may cause the charge to become less stable and potentially an early detonation resulting in a blown piston. The octane actually slows or controls the burn so the detonation will take place closer to TDC. So when you are performing mods that generate more HP, you produce more heat, and need to run a higher octane to prevent the charge from becoming unstable and detonating under the additional heat and compression before the plug fires.
 
Very true. I get a kick out it when i hear some say they got "race" fuel at the pump for their stock machines. Usually the younger kids in my area think they are really on to something there.
 
cajones2 said:
Very true. I get a kick out it when i hear some say they got "race" fuel at the pump for their stock machines. Usually the younger kids in my area think they are really on to something there.

Yup, lol pretty funny, you lose power running any higher octane than you need. ;)!
 


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