Turns out ecotrons have a 206 EFI kit… although it says junior
https://www.ecotrons.com/small_engine_fuel_injection_kit/efi-kit-for-junior-206-engine/
I agree LO206 is not the place. It would need to be in the shifter or high end two stroke. Shifter would be cool because it would make no lift shift a no brainer. As for 32,000 rpm comparison, I do not think it is a big deal. It is also the same as a 4000 rpm V8. If it is not direct injection then the fuel delivery does not care how often the engine fires. That could still be induction pickup with a simple device to advance or retard actively
Biland made one years ago. It is four-stroke, but designed to compete in the Tag Category.
Boasts 38 Hp @ 12,000 rpm and 28 Nm @ 8,000 rpm all on an outboard 219 chain/clutch setup. It weighs around 2 Kg/5 Lbs more that a Rotax Max Package.
I actually considered this until I realized they are not run it this country. Would be easy to spec with a sealed Electronics package like what Rotax and IAME use for their Rev Limiters/Ignition. No crazy last minute jetting changes before next heat. No futzing with the carb on course. You could just focus on Driving! Just let the CPU adjust Fuel & Ignition while you work on your Craft.
Downside: Might put a few Voodoo Track-Side Turners out of work, but the builders will still find a way to squeeze every ounce out of it (within legal limits…hard cough(blueprint)…snickers).
Just MHO.
I saw the carb version of that before. It was pretty cool
I thought that too until I talked with riley and others that were working on developing EFI for performance two strokes in single gear kart applications… It turns not it’s not that simple…
The two stroke still requires very different injection timing (Both pulse width and crank angle/pulse timing) compared to a four stroke. It’s much more sensitive than a four stroke where you can just (kinda) dump the right amount fuel in there and send it. The intake impulses, especially blowback play a bigger role.
Also, reminds me of this…
I am an electrical engineer for a living. I often say when you think something is simple it usually means you do not know enough yet to understand the details. I guess this is another of those situations. Now I am curious
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I’ve tried to entice Riley to join the forums but no luck so far 
One thing to note about the KTM is that the injectors are in the cylinder, injecting in the transfer ports vs the other side of the reeds.
I posted in a two stroke facebook group to see what feedback I get on EFI and two strokes…
On a 2 stroke, that sounds problematic. How would you lube the crank and rod with mixed fuel?
I think it had a separate oil feed at the bottom of the crankcase.
Actually, it’s oil injected via throttle body.
From How it Works | KTM TPI Fuel Injection Explained - ADB Magazine
In the KTM system, two-stroke oil is pumped into the throttle body, to lubricate the crankshaft, barrel, and eventually the cylinder bore and rings. Fuel is squirted into the cylinder via two injectors in the transfer ports, rather than into the inlet port or head.
Also, found this interesting…
From Two-Stroke Fuel Injection: KTM's Path To TPI - Dirt Bike Test
The window of time for the injector to be open and getting the large amount of fuel a two-stroke needs is the challenge, especially in even smaller displacements we are told. Plus when a two-stroke has a “flame-out” inside the combustion chamber, it can take up to 50 strokes for the engine to recover. This was a big issue in high RPM, low throttle times. For instance when you are going down a hill with the engine revving and then you give it a little gas. Making the throttle response as good as that antiquated carburetor was very difficult. There is not a lot of time for the computer to decide how much fuel and when to shoot it from one stroke to the next since the conditions inside the two-stroke engine can change drastically and very suddenly.
There we go. That’s what I wanted to get going.
And yeah I don’t see this as an interest in 206. But the 30hp classes is where I was thinking.
and lastly I’d love to see if they could do a 4 stroke that could compete in TAG. Be really cool to watch the different power bands and which teams choose what.
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There were actually a handful for the TaG class. OHC design, 250cc. SA250 was the most popular one. I went to search the web for more info and found a KP topic 
But they never really took off in the US.
Interesting. I’ll look into them. Just out of curiosity.
Edit. I guess they sound awesome. Looking for sound clip now
Riley (BRC) is local to me, they do some crazy cool stuff. Talking on the biland did one not win tag at skusa one year? They posted a recap video last night of I think it was 2006
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I was getting deja vu.
This won’t happen, karting will jump straight to electric. The only manufacturer I thought might do it would be Rotax, as they have the direct injection tech already with Evinrude. But they are going down the electric route.
If you were selling 10,000 of units or could make use of an injector from a mass produced bike/snowmobile/jetski, I would estimate (just from my experience working in the manufacturer of diesel engines) that you could get the injector down to sub $50. But I can guarantee karting manufacturers would sell them $200 because a carb costs a similar amount (or more).
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TM went fuel injected with the dirtbike range this year, but the reality is that in terms of a karting application it is incredibly unlikely to come in. We’re with carbs until the end of 2-stroke karting. I doubt the FIA will mandate it, and there’s little appetite in the market placed for a shift over in the recreational classes.
That is may be why timing is important. That becomes effectively direct injection.
I looked at this last year in some detail. Besides KTM, which wouldn’t sell me an engine directly, there were no other 2-stroke FI suitable engines for kart road racing. Really, FI makes the most sense with 4-stroke engines, something I can see karting and other 2 cycle sports being pushed towards as states also start cracking down more on all 2-stroke engines.
To get good low end torque out of slow corners AND high end performance with a 4-stroke, FI really helps. And it’s much simpler to meter since standard wideband O2 sensors and controllers can be used due to the lack of oil in the exhaust. Yes you need a small high pressure fuel pump, an injector, O2 sensor, computer, and a small battery to run it. Most of the weight added is in the engine with the valvetrain. So heavier and a little more expensive for the same power than a 2-stroke, but with a start and just run it experience like a 208, even on the coldest days.
And yes, I’d love to go there. A 449cc Kawasaki engine on a kart is something I may just build this year even though I’m not allowed to even provisionally kart “race” it due to nothing bigger than a 250cc engine insurance regulations allowed. 52.63 hp at 9,480 rpm and 32.80 pound-feet of torque at 6,730 rpm on pump gas should provide a lot of grins for the money, even if it has to be at the drag strip.
Typically this is the four stoke limit, although it will vary. There are CRF450’s out there running and racing.
Following up on the two stroke discussion… here’s some thoughts from the 2 Stroke Research and Development FB group. One noteable thing is that I don’t think any of these are regarding smaller 125cc engines revving to 15-16,000 RPM.
Nathan Coleman Injection time, consider injector open and close time not just the deadtime. Multiple injectors problem solved.
Consider effect of the exhaust on the airflow, tuned exhaust can increase inlet port airflow by up to 4x. Consider the exhaust is only active after combustion and that at small throttle positions combustion is irregular. Extremely dynamic air flow, need a sensor for it to compensate fuel on a per cycle basis… difficult!
Derek Laporte I run a turbo 2 stroke efi 1200cc twin with standalone vipec m800 ecu started with a base tune and worked from there it’s relatively easy when starting with a base tune it was way off but only took a day or 2 to come around on the dyno to come around and get it all mapped my friends at d&d Racing have done quite a few in the last few years and taught me how to use the program etc. We also did an efi twin 800cc with a stand-alone as well last summer I love efi 2 stroke and they work great but keep in mind these were efi from the factory we just swap out ecu to have full access and control of everything
Valery Rutkovskiy
I produce programable ECU http://www.flame-power.com/en/direct-en/programable-ecu-en and install it on my 2-strokes. Its programable, so you can adjust behaviour. Stihl have very clever fuel injection with minimal ammount of sensors. One man adopt Speeduino for 2-stroke. Whole history at kiwibiker forum.
Cédric Patouillet For me, it has been not as difficult as expected. The thing is just do your own experiments. For some reason the injector flow has to be way higher than the theory. So monitoring your duty cycle is important !
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