This is the Ossa 300i fuel-injected enduro bike. It was developed in 2011, but was not sold in the USA. The injector is dead center in the photo. Ossa was bought by Gas Gas last year and Gas Gas declared bankruptcy and was sold to Torrot of Spain—no word on the fate of Ossa.

Dear MXperts,
    Why are the manufacturers that make two-strokes (KTM, Yamaha, Gas Gas, Husqvarna and TM), dragging their feet on putting fuel injection on their smokers. It would solve the jetting issues forever and produce even better bikes. What’s the hold up?

The first question is how much do you want the price of two-strokes to go up? The second question is how much weight are you willing to gain on your two-stroke? The third question is what’s so hard about changing a jet occasionally? The major manufacturers have fuel-injected two-strokes sitting in the R&D departments that could be released tomorrow if the world demanded it — but let’s not put our faith in the mob majority of the modern world. The current two-stroke is simple, light and relatively inexpensive. The reason that KTM, as an example, doesn’t want to fuel-inject their two-strokes, at this time, is because they will gain 5 pounds, the price will go up a couple hundred dollars and the consumer will not be able to cure his woes with minimal garage tools. KTM will offer fuel-injected offroad bikes in the future to meet the stringent new Euro-4 emission rules (as for now they have stopped selling 125cc two-stroke offroad bikes in Europe).

It’s important to note that fuel-injected bikes do not produce more power than carbureted bikes — just the opposite. What they do produce is a broader, easier to use and flawless delivery of just the right amount of fuel for the X’s and O’s of the ECU. And they will idle like a kitten. However, motocross bikes often need extra fuel for an upcoming situation and that is what a carburetor is great at providing. It doesn’t stream fuel electronically via a pump, it draws fuel in via the demands of the suction created by the engine itself. Carbs are true-to-life “on demand” fuel systems.

Obviously leaving the jetting in the hands of a percentage of riders who often don’t know anything about how a bike works has its draw backs, but for the most part, once you get the jetting in the ballpark for your track and season, it doesn’t require an inordinate amount of time to adjust.

Arctic Cat produces a fuel-injected snowmobile engine.

There are fuel-injected two-strokes in the scooter, trials, watercraft, outboard engine and snowmobile marketplace. These engine’s intake and transfer processes handle only pure air. The fuel is injected only after the exhaust port closes — thus, they are more emission-standards friendly because no unburned fuel blows out the exhaust. But, motocross race bikes don’t need to be EPA friendly—they need to produce max power. Fuel-injected two-strokes will come on European offroad and dual sport two-strokes first and if we are very unlucky, it will trickle down from there to motocross two-strokes.

It is unlikely that any of the initial offerings of fuel-injected two-strokes will inject directly tot he combustion change, but more likely into the normal transfer port circulatory system. Plus the carb, or a version of it will remain as a way to control the amount of air via a slide or butterfly.

Fuel-injected motocross bikes will come when the manufacturers believe that they are ready for prime-time or that the market is willing to bear the brunt of the change or when government crack down on them. One last thing, be very careful what you wish for — especially if you don’t understand any of the ramifications. Fuel injection will not change how you ride your bike. It won’t make it any cheaper, lighter or more fun. It will just add complexity to a machine that’s saving grace is that it is simple.



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