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Flexible Fuel Technology: Motorcycles

They've got an Awful Lot of Ethanol in Brazil

Given how crazy Brazilians are about flexible fuel vehicles, it's amazing that there weren't any flex-fuel motorcycles available there (or anywhere else) until 2009. That's when Honda launched the CG150 Titan Mix, with Honda's patented Mix Fuel Injection System. What makes the Mix Fuel Injection System different from other systems is that it doesn't just let the bike use the standard E10 (10 percent ethanol) and E85 (85 percent ethanol) mixtures that most flex fuel engines use. It can use almost any mixture of ethanol and alcohol, up to 100 percent ethanol, by monitoring the oxygen content of the bike's exhaust and detecting what percentage of gasoline and ethanol the engine is receiving, and then adjusting engine function to take advantage of the exact percentages. Because of problems using ethanol in cold weather, a warning light tells the rider to adjust the system for a special cold-weather mix to prevent the fuel from freezing.

The Titan Mix, which runs at 14.3-horsepower at 8,500 rpm on pure ethanol, proved to be just the first in a line of flexible fuel motorcycles from Honda:

  • NXR 150 Bros Mix, an on-off road bike that runs at 14-horsepower at 8,000 rpm on pure ethanol
  • GC 150 Fan Flex, which runs at 14.3-horsepower at 8,500 rpm on pure ethanol
  • BIZ 125 Flex, which runs at 9.1-horsepower at 7,500 rpm on pure ethanol

And if you're not up to the challenge of importing a motorcycle from Brazil, there's a do-it-yourself option available. Oddly, flex fuel bikes don't seem to have caught on (yet) outside Brazil, but it's possible to retrofit your own motorcycle for flex fuel with higher ethanol content than 10 percent. A company called claims to have a conversion kit available that will convert a motorcycle to full flex fuel compatibility.