Honda Files Patents for Brand New FI 2-Stroke Engine

Bryan Bosch

Two-strokes are far simpler machines than four-stroke engines. They’re also lighter, easier to work on, and downright angrier, pumping out a lot more power per cubic centimeter of displacement, which has won them a lot of fans. But they’ve had a reputation for belching out a fair bit of smoke and unburned fuel, a situation that just couldn’t fly alongside tightening emissions regulations around the world, so they’ve fallen out of favour. But now there’s a glimmer of hope. Earlier this month, Honda submitted a patent application for a brand new two stroke motor that uses direct fuel injection for a cleaner burn and better piston cooling. We may yet see a resurrection of the ring-dingers.


Full Article @


Link to PDF of Patent App @





User Feedback

Bottom mount Push rod engine. HIGHLY doubtful to be used in a motocross application.... but hey... if they make 1 why wouldnt the make others?

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I don't see how the fuel goes thru the reed assy, lubes the crank, etc, then goes where?fuel mix goes up to intake port, or...? AND the valve is used for what, straight gas injection, or.....? I understand D.F.I. technology, but im tryin to see how it lubes w/oil on bottom, and injects fuel on top, therefore gas burns and oil mostly lubricates and doesn't "burn" in the traditional fashion.....

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Im waiting for Bombardier to make a high perf 2 stroke for the cycle industry, THAT would kick-ass!! They do it in their ski-doo sleds, (E-tec d.f.i. )so day maybe.....into bikes!!!

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I first worked as a mechanic in a Honda shop in 1965.   Early on, it was clear that Honda made a really excellent product, especially in those dark days of Lucas electrics and oil leaks.  I don't presently own a Honda bike, but will always be a Honda fan and am thrilled to learn they are moving into developing an emissions-compliant 2-stroke engine.  If anyone can "get it right", it's the folks at "Big Red".


Bravo, Honda



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