Ethanol Gasoline and Fuel-Injected Bikes


Motorcycle Classics tech expert Keith Fellenstein
Editor’s note: If you’re having trouble with that old Suzuki, BSA or BMW, Keith Fellenstein is your guy. From motorcycle tuning tips to detailed motorcycle engine repair, he can draw from a wealth of experience to help guide you to success. Send questions to: Keith’s Garage, Motorcycle Classics, 1503 SW 42nd St., Topeka, KS 66609, or send an email with “Keith’s Garage” as the subject.

Q: I enjoy reading your column every month and I turn to you with a question. Are fuel-injected bikes less affected by the ravages of ethanol gasoline than bikes with carburetors?

- Robert Lazzaro
Hopewell Junction, New York

A: The short answer is no, ethanol affects fuel-injected bikes too, but in different ways. The fuel still seems to go bad faster than pure gasoline, and will still draw moisture out of the air. Most fuel-injected bikes are going to have a fuel pump, which can get gummed up and seize. I suppose the injector nozzles could crust over too, but would hope the injector pressure would overcome that. My routine for
carbureted bikes is to turn off the taps on the way home and try to enter my garage on fumes to help keep the carburetor bowls clean. Since you can’t do that with a fuel-injected bike your best bet would be using a fuel stabilizer additive. MC

8/22/2019 3:23:53 PM

More useful would be to A) Direct people to websites that tell you where you can purchase clear gas (Alcohol free) and be aware, that many small engine manufacturers tell you it voids your warranty to use E10 and be aware E15 is coming. B) Learn how to seperate out the alcohol in fuels. (Not hard, multiple websites show how) C) Contact your local elected officials to explain how badly these fuels damage engines and thats its false economy. Not only do engines run worse (Our cars see a notable increase in fuel economy with non alcohol fuels) but it damges systems causing more expense and pollution. But its the biggest scam foisted on the consumer since I dont know when. Corn and other ag products to produce ethanol are not cost effective and only exist due to generous govt subsidies and incentives. Until Farmers learn to run solar powered tractors and equipment its also consumes a lot of fuel to farm it.

8/22/2019 2:52:34 PM

In Texas, I can only find 83 or 87 octane non-ethanol fuel. Is it ok to run 87 in my 1200 Moto Guzzi and the RC 51?? I have ready access to 100 low lead aviation fuel(great shelf life!), and I use if my vintage bikes; but I worry about the lead and valves on the newer models. Your advice please.

8/22/2019 12:54:25 PM

E10 Gasoline is not so good for Injected Bikes, either. 1st and foremost E10 makes an injected bike run lean. Open loop ecm programs have been designed to deal with this issue, (as of late) but the older injected bikes such as BMW R and K series run into this problem. With catalyzer, and especially when removed these bikes run lean which equals-HOT. The O2 sensor and Cat on BMW bikes of the late 1980's to late '90's (read 'Closed Loop') compensates to some degree. But on the early R bikes which had no Cat, they had a C.O. trimmer. This required an emissions tester to set the AFR, (air-fuel ratio). I've performance tuned plenty of R1100 BMWs and with the Catalyzer and O2 sensor removed I have always suggested running pure 100% octane 90-91 gasoline. They just run better. Marathon Stations in the south, (not all) sell 90 octane pure gasoline, particularly around bodies of water and communities with gas-powered golf carts. Up North pure gasoline with a ROM of 91 can be found at Stewart's Shop Gas Stations. With the U.S.A. becoming the world's foremost energy producer under Trump, I expect to see ethanol blended fuels taking a dive in favor of pure gasoline. E10 to E85 has a huge myth attached to it: it's expensive to produce, Corn crops do not produce at a rate which is effective for global fueling consumption, and the BTU of grain and corn alcohol is so much lower. Not at all a truly effective performance fuel. Learn about "British Thermal Unit" of particular fuels and you'll begin to understand why alcohol is truly worthless as a performance fuel. JackPowersIII

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