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I'm wondering if it will be okay to run 100 octane low-lead aviation fuel in my 2007 RM250 motocross bike (two-stroke). Half of the people I've asked say yes, while the other half say no. Will it be okay to run aviation fuel in this high RPM two-stroke engine?

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2 Answers 2

up vote 4 down vote accepted

You can, but you'll significantly reduce the life of your engine. That's the short and to the point answer. I don't know too much about bikes, but if this were a car, I'd at the very least have someone tweak the carbs and adjust the timing somewhat.

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I can't recommend it. I was told that 100LL has about 4x the lead that the old regular leaded fuel had. Even on aircraft (which run at or near 75%+ power continuously) lead fouling of plugs is a major issue with frequent cleanings required.

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And airlines are allowed to foul up the air with leaded fumes? – Cynthia Avishegnath Oct 30 '13 at 7:17
Airlines don't use leaded gas. They use Jet A (fancy kerosene really). It's the small airplanes that use leaded fuel. It's a rather unfortunate thing, small airplanes were slowly migrating to unleaded. However, unleaded started getting ethanol added to it. Ethanol is illegal in airplanes. So, once ethanol became the big thing in unleaded fuels, airplanes were forced back to leaded... – Brian Knoblauch Oct 30 '13 at 15:43

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