EFI for Two-Strokes Is Close!
It is no secret that KTM has been testing fuel-injection on two-strokes for some time. They have been as quiet as possible about it but keen eyes have spotted it out in public. Now at the Roof Of Africa it isn’t being hidden much at all.
Andreas Lettenbichler and Lars Enoeckl have the FI equipped KTM 300s running in a race that has a big variation in both elevation and temperature to shake out the bugs. A great real-world look at how fuel injection can benefit even a two-stroke. The reason for resisting FI has been cost and complexity but times are changing. With new emissions standards coming quickly in Europe and the popularity of the two-stroke world-wide, something has to give. The parts on the bikes, according to people very close, are very production looking. But the could also be sourced from current four-strokes for the most part. The complexity is in the electronics controlling the system. The current two-stroke already has the power to run the system and squirting fuel into an engine through an injector is nothing new. Having a little pre-mix blended in does not cause any issues.
The cost of carburetors is actually increasing to a point where the FI parts may be even less expensive in total. From a production standpoint it is the development time to get the mapping just right that saddles the cost. Two-strokes are said to present some unique issues due to wildly varying exhaust temperatures and differing compression ratios based on RPM and exhaust valve movement–somehow the antiquated carb deals with these issues just fine. Or did they? Time will tell.
The advantages are said to be many. Like increased fuel efficiency, longer power spreads, less loading up and even better throttle response. Some of the “hit” that riders love from two-strokes may actually have to be programmed back into the mapping as that burst is the engine “catching up” to the burst of fuel and air. Sherco has a running FI two-stroke and even Ossa has a production two-stroke trials bike that is FI.
When will we see this? We can not be sure but our educated guess is 2019 for full production from KTM and Husqvarna. Do not be surprised if you see a “special factory edition” type from KTM even sooner. We know they have been working on jetting the Mukini carbs on the current XCWs and SX bikes and that typically becomes less of a concern if they do not need that information for next year.
News about the TPI Two-Stroke: