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.
Link to PDF of Patent App @ http://images3.freshpatents.com/pdf/US20150184574A1.pdf