Inovations In Two Stroke Direct Injection

By Jerry McCommons

As we all know, there are no two stroke engines in Moto Cross at the present time. You can, however, believe me. There are people working on this issue as I write this. I’m going to show you some examples of what’s out there now and what we might expect in the near future. The concept of fuel injection is hardly new and many of the mechanically inclined are familiar with its operation. I’m going to start from the beginning and refresh our understanding of the previous incarnation of the 2 stroke operating system. The following video may be old news to many but, bear with me please, since some of our younger readers may never have had the theory explained clearly. The following video will explain the operation of many 2 stroke engines .

Again, bear with me as many riders have never had to work on this easy to maintain simple design. I can tell you from personal experience, even the most inept mechanic can repair the 2 stroke engine. Next we’ll examine the operation of the 4 stroke engine that power the current crop of dirt bikes offered for sale. This is also the operating system in the car or truck you drive.

As many of us know in the motorcycle application this can lead to costly part replacement due to the nature of the high rpms needed for current power demanded by the subsequent high performance demands of competition. There we have it. 2 strokes produce unburned exhaust gases which lead to their demise. I can tell you from hours of research, there are many companies working on a direct injection in the 2 stroke application to reduce the unburned fuel/air mixture. Here we have a very informative video of its importance.

That pretty much hits the nail on the head. The only problem is that this improvement is typically used on very small displacement engines.

Next we’re going to take a peek at its application in larger engine designs. It is in use and has been for a few years now. Its use in snowmobile and outboard motors allow for much larger engine displacement than the previous example.

The rub is, the engine will generate high rpms but, it’s not subjected to the quick on-off power needed for motorcycle completion use. The following will clearly demonstrate that large numbers of companies that rely on the direct injection engine are working on this problem.

Anyone as old as myself will surely remember the Lotus organization from it’s Formula one days. Through the miracle of facebook, I had a chance to chat with an engineer who was working on this design. (She was a very nice woman) This next video comes a little closer to what we’re looking for here.

Any of you who are currently riding the current crop of 450s, you have no idea the horsepower that’s produced by a 2 stroke 500cc motor. My riding buddy rode one for years. It would hurt you if you weren’t paying attention. I learned that lesson the hard way.

The only question is, why aren’t the manufactures aren’t offering this to the buying public. Well there are a couple of reasons. First, they’ve invested huge amounts of time and engineering to bring us the current crop of open class bikes we have now. If they Scrap that design, it means engineering and retooling their assembly line. Second, as shown in the video above, the horsepower delivery can and will be brutally violent. Anyone who’s ridden an old 2 stroke 500 will confirm. I’m a little surprised that Honda hasn’t snapped up this highly inventive design from our friends down under. Having been an employee in one of their shops, I can tell you they are sitting on a great many creative engine design formulas like spherical valve technology. When they’ll put that into use remains to be seen. It’s advantage. It’s imposable to float a valve even in the event of catastrophic engine failure. We can only hope that one of the current manufactures will put a Direct Injection 2 stroke on the showroom floors. Simple to maintain. A hoot to ride due to their snappy power delivery. It is something we’ll get but, not without the demand from the riding and buying public.