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HONDA files patents for brand new, fuel injected two-stroke engine

Ive been waiting for this to happen… I say the 2 Strokers arent dead YET … At least I would enjoy seeing them return. Ive had a long love affair with those little engines. Im betting that many people on here have had a similar experience?



I don’t see anything on that engine that hasn’t been done already except for that unusual crank configuration, which has nothing to do with two stroke operation. That crank could easily be used in four strokes, steam engines, or air compressors.
Direct injection…already done
Poppet valve head uniflow design…already done.

True…but a company like Honda wouldn’t file a patent if it thought it was frivolous. Doesnt matter what has been done in the past… it matters how Honda groups the terms on their engines. Other inventors have been on the right track with familiar concepts and principles and then failed to hit the mark.

No matter what has been done before…it just matters if you can pull off the goal in the end…which I am certain is the taming of the exhaust emissions and oil/lube management.


I am curious re the articulated crankshaft throw but saw no mention of it in the write up. It would appear that the piston speed at BDC is significantly slower than at TDC but it’s difficult for me to visualize exactly how the crank/throw turns on the crankshaft.

I just read the article, and it sounds like it may not initially be intended for automotive use, but rather for industrial use

That would be more appropriate, IMO

In any case, it doesn’t generate much excitement for me :neutral:

If I have to work on the technology some day, so be it

I don’t get as excited about certain technologies, versus some of the other regulars

So sue me for lack of interest :tongue:

A regular connecting rod gives lower piston acceleration at BDC than at TDC. I’m not sure what they are trying to accomplish with that articulated crank. A slow compression stroke and a fast power stroke?
I remember going to an oil field because there was a problem with a single phase motor driving the oil well pumpjack overloading at the bottom of every stroke of the pumpjack. I was studying the motion and noticed that the jack was dropping the sucker rod slowly but lifting it fast. I suggested that if we reversed the motor rotation, it would lift slow and drop fast. So we reversed the motor rotation and the problem was solved.

I always thought 2-strokes were too dirty to get certified for on-road use. Granted, a DI 2-stroke is going to be much cleaner than a carbed 2-stroke that vents much of the fuel-air mixtuee directly to the exhaust…but 2-strokes are still dirtier. The Detroit Diesel 2-stroke ultimately was abandoned due to tightening emissions.

That patent drawing looks like some sort of industrial engine to me. Also, Honda sells engines all over the world, not just in the U.S., and not everything they make is available to the U.S. market.

OMC (Johnson-Evenrude) has been making and selling direct injection 2-stroke outboards for many years now…They are clean, powerful and reliable…OMC is long gone, I think Bombardier makes them now…

@Caddyman Yes, Bombardier Recreational Products (BRP) bought the assets of OMC after they went under. This is a separate division of Bombardier which also makes airplanes, commercial tracked vehicles, and trains.

They also own the Rotax company of Austria, a reputable maker of small engines.

Here in Mexico, almost all private houses are made of block, bricks, and concrete. They use a lot of concrete. Places which sell large quantities of cement sometimes have gas powered mixers, on wheels for towing behind pick-ups, which they loan to those who buy the cement from them.

Need I say the best ones have Honda gas motors?

I bet 90% of patents never result in a real product. We’ll see…

Honda wouldn't file a patent if it thought it was frivolous

Perhaps, but I wouldn’t be quite so certain. When I first entered the tech field in the 1970’s, a technology company would file maybe 1/2 dozen patents protecting the basic methods on which a product worked. That was done to prevent a competitor from copying your product outright. If a scientist or engineer wanted to patent on the product beyond that, they’d often be discouraged, for fear it would reveal some important trade secret, the set of which is the actual technical advantage a company has over its competitors. So why reveal those by filing patents?

Patents these days are sought out far more commonly and frequently . The reason is they are used as ammo in patent wars when there are legal battles between companies competing in the same market. The two companies will try to secure as many patents as possible, so they’ll have more to say than the other at the intellectual property trial. These days they’ll patent ideas they don’t intend to use, just to prevent other companies from getting those patents first and having more legal-ammo than them. It’s sort of a patent mind-game these days. In most science and engineering teams these days there’s usually at least one experienced engineer who’s main job is – not designing products – but filing patents.

Honda powered waterpumps spoiled me.@IR, I wish more houses in america were of the heirloom masonary construction,the Americans with plenty of disposable income dont seem to care that the houses are not made to last ,we probably use more wooden construction then any other country in the world.It never ceases to amaze me how often people seem to get the urge to remodel,almost as often as changing cars it seems .
Madison AVE ,has done its work .

we probably use more wooden construction then any other country in the world.

Isn’t that a byproduct of wood being plentiful, cheap, renewable, and easy? Concrete is expensive and requires special equipment to manufacture, transport, and install. But even today anywhere I’d want to build a house I would have to clear trees away first. Shouldn’t I use those trees to build the house?

Sure the bib cabin is lg construction, beautiful logs on the inside, Our carpenter was like a dentist, replacing rotted wood with concrete. Now I am going to an epoxy injectable, ie abatron if anyone is interested, but until divorce intervened was looking at concrete poured walls around styrofoam for a very energy efficient house.

Actually I’ve never liked 2 stroke. Just too noisy. Back when we were kids I remember Popular Mechanics had an ad for brand new Clinton 2 stroke engines for $5. The neighbor kid ordered one for his mini bike. I didn’t want to spend the extra $5. But it was noisy compared to my 4 stroke Briggs.

Yeah agree with wood being plentiful for building. In some countries though, houses are passed down from generation to generation so stone makes some sense, especially if there are no woods around. The other thing is my house has 6" of insulation for whatever R value that comes out to-20 some anyway. My son has stone and did some remodeling. We calculated the R value at about 3 for the walls. Stone does act like a heat sink though to cool the house in the summer and maintain temp in the winter but still not suitable for Minnesota without insulation.

Honda built a V-4 engine with oval pistons just to spite the AMA 50 years ago.

Yes, indeed. Four stroke engines are so inherently quiet that they don’t even need mufflers, just ask any Harley Davidson owner.
They’re so quiet that these people are cupping their hands behind their ears just so they can hear it better.
photo Stewart-Q1-leave-1-DE.jpg

Well, my house is 100 years old, and wood construction (brick facade but not structural). I don’t see why lasting construction can’t use wood as a building material.

Also, there’s ecology. Wood is renewable. Concrete, OTOH, requires a HUGE energy investment to create (heat needed to create the lime for the cement).