2 stroke an FI

[lankydoug]

http://motocrossactionmag.com/news/ask-the-mxperts-whats-holding-up-fuel-injected-two-stroke

 

[troy deck]

i'll admit i never tried it and i dont think i want to

 

[juicypips]

Lectrons holding up fuel injection!!!

 

[ray_ray]

Please, no more ossa .... That is as far as I got on that article ...

EFI \ DI \ whatever is not gonna be what we call a 2t today ... Might change my mind later but I have zero use for any 2t bike that does not have a CARB.

 

[Dangermouse449]

Hopefully, one day, someone will bring it to market & clean these stinkers up.
I think the anti-tech guys will be surprised by the gains.

 

[lankydoug]

If you've ever been around the DI 2t snow machines or the outboard boat engines you will realize the potential. In my opinion a 175cc DI 2t would be about all a dirt bike would ever need in power and the power is also very smooth. DI four strokes are probably coming someday as well. They are here on automobiles and working out well.

 

[racemx904]

as long as Ossa is building it both people that buy it will have fun... until a real player makes it not many will see it... either they havent profected or they feel its not viable

 

[ray_ray]

Just show me the baby, the real baby in a showroom, and not that green one from outer whereEverVille that apparently has become the holy grail of this saga.. Then we can all purchase and start testing this new invention for the companies ... Yippee and the beat goes on...


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Here's a little history on outboard engines ... I'll add, motorcycles throttles are opened and closed over and over in the right and wrong gears, uphills, downhills .. Totally different from boats and maybe snow machines ... The coding for it has got to be much more complex ...​

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Evinrude outboards produce two_stroke DI engines ranging from 25 hp (19 kW) to a 3.4L V6 300 hp. They used carburetors until the late 1990s, when EPA Clean air regulations mandated new technologies. OMC partnered with FICHT, of Germany to introduce Direct Injection. Unsurpassed Durability testing took place, and Production Started prior to another round of EPA Regulations. Modifications were made at that point to bring the motors up to standards. these modifications were not carefully engineered and designed and caused powerhead failure and even a recall on the motors. The losses on these motors, the loss of reputation and the surge of competition from Japan and Mercury, pushed the company into Bankruptcy in 2000.​

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Not gonna read that article for yet another or the same angle repeated but who wants to risk what, for what?​

Our physics allow man can go as fast as light .. I'm ok with potential but it will not be reached anytime soon ... At the speed of light, time stands still... Ain't that cool?​

 

[juicypips]

Lol ray ray if time stood still at the speed of light how would my lectron supply fuel to the motor? How would the piston move it wouldnt happen! Im gunna stick with what i know and already own for a fair while. Fi? Fu#% it!

 

[ray_ray]

Good question on the fuel supply ... Your CARB is gravity fed ... Not sure on gravity at the speed of light ... FI is here same as a tuxedo .. But do we all need one?

 

[Theo]

Some years ago, I had a 50 cc 2 stroke moped with direct fuel injection:

I used it mainly to commute and I wanted it to be as street legal as possible and as reliable as possible. When I sold it, it had about 10k miles and it never gave me any problem.
Using something like this (even without direct injection) on a racing bike like an MX bike would be different, because many people modify their two stroke bikes in order to have a different power delivery. So, IMHO, FI could be successful if there were tools like this for their ECUs, but that would mean spending even more money.
Still IMHO, FI for two strokes would be great to make street legal bikes, at least here in Europe where apparently it's hard for two strokes to comply with antipollution laws, but the average amateur racer would prefer the carburetor, and maybe the professionals would, too.

 

[justintendo]

on a fuel injected 2 stroke, how does the ECU make fuel delivery adjustments? i cant see a 2 stroke using any kind of O2 sensor. how would the ecu know whats going on with the engine or know whether to subtract or add fuel? i guess it could operate in a constant open loop setting, but that wouldnt work well. perhaps some sort of mass airflow sensor that meters air flow which would determine engine fuel demand? tps for throttle input and of course a tach input. would have to be some sort of position sensor on the powervalve so the injector pulse width could increase when the valve opens. a tach input as well of course..
ambient air temperature sensors would let the ECU know about whether, map sensor would work for elevation.
i guess if a smoker would burn clean enough an oxygen sensor could work, not sure.

im still on the lectron train tho, plenty smooth and accurate for me

this old ad is kinda ironic, todays carb on yesterdays engines!!

 

[ray_ray]

Just, here's a little help on your grammar and spelling. Only can spend about 12 minutes here so it might need some more fixin'....

On a fuel injected 2 stroke, how does the ECU make fuel delivery adjustments? I can't see a 2 stroke using any kind of O2 sensor; how would the ecu know whats going on with the engine or know whether to subtract or add fuel? I guess it could operate in a constant open loop setting, but that wouldn't work well. Perhaps some sort of mass airflow sensor that meters air flow which would determine engine fuel demand? TPS for throttle input and of course a tach input.

Would have to be some sort of position sensor on the power-valve so the injector pulse width could increase when the valve opens. a tach input as well of course.

Ambient air temperature sensors would let the ECU know about whether, map sensor would work for elevation.

i guess if a smoker would burn clean enough, an oxygen sensor could work, not sure.

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I'm not an engineer and well behind the power curve on EFI\DI stuff but you seem to be well on the way to that title... Maybe someone can help you with your assumptions on the thread topic and we can make this 2t EFI reality?

 

[rasputin]

Some years ago, I had a 50 cc 2 stroke moped with direct fuel injection [...] When I sold it, it had about 10k miles and it never gave me any problem

Ditech (Orbital) is not a direct injection system. It's an "air-assisted" system.
That air pump (blue part near the crankshaft) is a wearing part. I'm surprised that it worked for 10.000 miles.

FI for two strokes would be great to make street legal bikes, at least here in Europe where apparently it's hard for two strokes to comply with antipollution laws,

The emission regulations in California are harder than those in Europe. Bytheway. fuel injection "cures" the exhaust emission problems, but it does not reduce the noise emissions.

on a fuel injected 2 stroke, how does the ECU make fuel delivery adjustments?

rpm sensor, throttle position sensor, air pressure sensor. Alpha-n 3D map (rpm, load). Closed loop.

r

 

[Theo]

Ditech (Orbital) is not a direct injection system. It's an "air-assisted" system.

Here it was advertised as a directly fuel injected engine and, as a matter of fact, "ditech" stands for "direct injection technology". Besides, in the drawing I posted you can see that the green liquid, id est the gasoline, is injected into the combustion chamber and here you can see both an air injector and a gasoline injector on the head.
Therefore, sorry but I really don't understand why that's not a direct injection system...

 

[rasputin]

The fuel does not go into the combustion chamber directly. Air from the air pump (light blue in the drawing) goes into a "pre-chamber", and fuel is injected (green colour) into this pre-chamber. Then, this air/fuel aerosol is injected into the combustion chamber.
That's because the fuel needs a certain time to vaporize and mix with the air.

r

 

[justintendo]

The fuel does not go into the combustion chamber directly. Air from the air pump (light blue in the drawing) goes into a "pre-chamber", and fuel is injected (green colour) into this pre-chamber. Then, this air/fuel aerosol is injected into the combustion chamber.
That's because the fuel needs a certain time to vaporize and mix with the air.

r

indirect injection? lol

 

[Tinken]

You can add an Ecotron 2 stroke fuel injection to most bikes. The ones I have seen do out perform the normally aspirated ones. But direct injection is definitely where it's at.

 

[robertaccio]

my friend and ride crew member has the OSSA injected trials machine in his stable, they were/are out on the market...last I heard Gas Gas bought OSSA.......then they went out of business too......

 

[justintendo]

You can add an Ecotron 2 stroke fuel injection to most bikes. The ones I have seen do out perform the normally aspirated ones. But direct injection is definitely where it's at.

interesting site tinken, just glancing it over solves a few of my questions..
they do in fact use an oxygen sensor, but its optional. can also be removed after initial tuning is performed to avoid ruining the sensor. i see ecotron uses exhaust gas temperature sensors, thats a pretty accurate way to tune. i know those are big in snowmobile and microsprint circles...
ecotron seems to hint at running in open loop once you have your setup dialed.