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Maybe, maybe not, but Honda did just recently publish new patents that show they're at least thinking about 2 strokes in some capacity.

Development of 2 strokes has slowed considerably alongside tightening emissions regulations. The brappers as most know them are famous for their blue black belches of smoke and unburned fuel, but they also go like lightning, are far lighter, simpler and pack a whole bunch of power into a compact package.

The patents were discovered by Morebikes.co.uk on July 17th 2015, originally filed by Honda on October 15, 2014.



In Figure 1, numbers 71, 70 and 74 delineate a fuel injection system "mounted on the engine main body so as to inject fuel onto a back side of the piston and/or part of the side wall of the cylinder bore". Mounted low in the cylinder and angled upwards, "located under the piston via the open end of the scavenging port or via the open lower end of the cylinder bore". The fuel is sprayed as a mist over the scavenger port and "deposited on the surfaces of the piston and the cylinder inner wall promoting the cooling of such parts"

Honda believes that they can eliminate most of the complexity that has dogged other fuel injected 2 stroke efforts.



However its not all joy. This design may not be for motorcycles. The diagram seems to show a long-stroke engine, including pushrods, in Honda's opening statement they say "the two-stroke engine is often preferred over the four-stroke engine in the field of general purpose engines because of the simplicity in the structure.". Further on they mention elsewhere that "the fuels that may be used for this engine include gasoline, diesel, kerosene and utility gas"

It's starting to sound like a fixed RPM generator...

Of course it's also possible that this is the general makeup of Honda's next generation 2 stroke technology, its believed that Husqvarna/KTM are sitting on their own clean 2 strokers, biding time until either the market is ready or costs and complexity are able to be reigned in.
 

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I don't know if they can ever get past the perception that 2 strokes are dirty. Just look at the slog diesel is currently going through. Would be interesting though as everyone trys to reduce displacements for emission considerations, clean 2 strokes could provide a more power dense solution then simply downsizing...
 

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Interesting design, particularly the crankshaft with the added link and concentric piece which looks like it creates a longer stroke, as shown in figure 1.

It doesn't look like a bike engine though. My guess is it is a stationary engine, based on the mounting flanges at the bottom of the crankcase, as would be used in a generator, or other stationary power equipment.
 

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I don't know if they can ever get past the perception that 2 strokes are dirty. Just look at the slog diesel is currently going through. Would be interesting though as everyone trys to reduce displacements for emission considerations, clean 2 strokes could provide a more power dense solution then simply downsizing...
BRP has been manufacturing clean 2 stroke technology in both their Evinrude E-TEC outboard motor and Ski-Doo snowmobile line for a number of years now...

Evinrude E-TEC Outboard Engines | BRP USA
 

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I used to work at American Honda in the motorcycle division. As a company, Honda has never liked 2 strokes. Case in point, their 1961 victories at the Isle of Man TT were on 4 strokes, while the competition used 2 strokes primarily.
And again in 1979 Honda went to race in the 500cc GP championship with the NR500, a V4 that was in essence a V8 with a couple cylinder walls missing.
The execs at Honda want clean engines, and with no real development in 2 stroke technology, they will in all likelihood stick to their 4 strokes.
 

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Blue smoking, environment polluting 2 strokes are only so, when they have low internal engine tolerances, and too much oil in the gasoline.
Most engines now run on a 50:1 ratio, and from the exhaust gas, you wouldn't be able to tell if it is a two stroke or 4 stroke.


It appears Honda is combining their offset cylinder design, with fuel injection on a 2 stroke.
Kymco is using fuel injection in their 2 stroke scooters for a while now.
 

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Most engines now run on a 50:1 ratio, and from the exhaust gas, you wouldn't be able to tell if it is a two stroke or 4 stroke.
Ive been using two stroke chain saws for nearly 30 yrs now and in that time Ive seen them progress from plug fouling, poor starting mongrels running a 25:1 mix to civilized modern era motors purring on 50:1

Ps. Welcome back MeeLee :)
 

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What is interesting about the patent drawings in the opening post of this thread, is not the EFI throttle body mounted on the crankcase, as that is what is commonly known as 'case reed intake scavenging', which is nothing new and has been in use for decades in two stroke engines. My 1999 Ski-Doo Summit 600 snowmobile engine has Case Reed Induction.

Nor is the exhaust valve in the cylinder head is anything new (ie. A.G. Stihl's patented 4-Mix engine, as is currently used in that company's line of chainsaws and other powered yard equipment).

But rather what seems to be unique to this Honda engine design is the extra crankshaft linkage shown in the fig.1 side view. Of course, one would need to see the actual patent filing in full in order to ascertain what Honda's proprietary and unique claims are for this engine design.

I recall many years ago that Ford Motor Co. had been working with a company by the name of Orbital on a new (at that time) two stroke hybrid engine concept, for use in a small urban commuter car (about the size of something like GM's Smart Car, or Fiat's 500). Never heard anything about that Ford/Orbital engine since.
 
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