TWO STROKE no smoke coming soon

[mossy1200]

Orbital’s air-assisted direct injection technology (ADI) separates oil and fuel, keeping oil out of the combustion process and surrounding the fuel vapour in a plume of air which allows clean combustion in the short time the two-stroke cycle allows. The injection of the charge happens after the exhaust port is closed, so none is lost.

Does this render the expansion chamber useless as all the fuel burns in the cylinder?

the rs500 still has expansions.I think there is still some oil burnt but down to 20% of the amount.Residual oil will still be in the bore area during the next cycle one would imagine.I think that they mean no visible oil and what remains is of an amount that can be cleanly(at least euro three cleanly)burnt away.

[bogan]

Orbital’s air-assisted direct injection technology (ADI) separates oil and fuel, keeping oil out of the combustion process and surrounding the fuel vapour in a plume of air which allows clean combustion in the short time the two-stroke cycle allows. The injection of the charge happens after the exhaust port is closed, so none is lost.

Does this render the expansion chamber useless as all the fuel burns in the cylinder?

Expansion chambers work with the reflected pulses from exhaust gases, rather than burning the fuel inside them. The burning part of the combustion cycle is actual very small, its the heat this releases that generates the massive amounts of pressure. So in theory the engine and expansion chambers etc should be largely unaffected by this technology.

[rocketman1]

Wow a V1000 2 stroke, I can just imagine how that would go.
I love the simplicity of the 2 stroke motors, no cams, cam chains valves as such and valve springs, plus the simplicity must mean ...cheaper.
Way to go: I for one would buy one.

[Spyke]

Expansion chambers work with the reflected pulses from exhaust gases, rather than burning the fuel inside them. The burning part of the combustion cycle is actual very small, its the heat this releases that generates the massive amounts of pressure. So in theory the engine and expansion chambers etc should be largely unaffected by this technology.

True I always thought that the pipe pushed the unburnt fuel back into the cylinder with the new mixture. I think I have to read so more lol.

[bogan]

True I always thought that the pipe pushed the unburnt fuel back into the cylinder with the new mixture. I think I have to read so more lol.

currently it does do that. It is my understanding that with the new system the expansion chamber will still push clean air back into the cylinder (some will go out the exhaust as well, but containing no fuel it isnt bad for emisions), the air/fuel injection will just put in a very fuel rich charge which will even out to the stoic ratio with the air from the expansion chamber, ill assume theres an oxygen sensor in the exhaust or something

[aewilliam]

Just below the 450cc 2T vs 4T chart:
“Everyone, except Honda, is harbouring significant two-stroke thoughts”

Dare I say, only hetero's and closet hetero's would harbour two-stroke (in an internal combustion engine sense) thoughts.

[Jantar]

My wish is coming true.

1000cc V twin 2 stroke.

[imdying]

Your not going to want old school power band style power with 200hp.

No no, you're not going to want it... me... the thought gives me major wood

[tigertim20]

After thinking bout it some more, why are the power figurs for this design so far down from older two strokes, 250cc two get compares to 450cc fours, but they are comparing 450cc twos to 450cc fours, granted the twos are ahead, but not by as much as they used to be. Whats going on? if the new two stroke designe doesnt ride like classic two strokes, nsr's kr1's etc itll be somewhat of a letdown.

My understanding of it was it is an effect of the mapping they are doing to the bikes, mapping the engines to provide smoother power curves, eliminating the 'peakiness' of the power older strokers have. Which seems silly, I dont care about emissions! I dont care if everytime I open the throttle a mother duck and 4 of her ducklings keel over dead from pollution, I just want POWER!! I like strokers for the differences they have to 4 strokes. I don't really care that it will be a little cheaper to buy, I dont care that it will use a little less fuel, I dont care that its 'cleaner' I would prefer and old school style mental powerband, tear your arms out of its sockets stroker power band!

No no, you're not going to want it... me... the thought gives me major wood

seconded!!

I am looking forward to riding one on the flesh though, just to check it out, but if it dont have the old stroker style power delivery, I aint gonna be buying one

[bogan]

i agree, though i do care a little bit about fuel emmisions, and fuel economy. I see no technical reason for them to smooth the power out, maybe they were meaning on the bigger bikes, i mean a 450 (dirt) or 1000 (road) cc two stroke would require a wee bit smoother powerband in order to be rideable. As long as they leave 125s with a big powerband ill be happy, and probably buy one, or two.

[mossy1200]

No no, you're not going to want it... me... the thought gives me major wood

Wood what they make fence posts out of.Any more than 200hp and every one would find out what they feel like.Remember they are claiming more torque than a 4stroke and 30% less motor weight.

[Armitage Shanks]

My understanding of it was it is an effect of the mapping they are doing to the bikes, mapping the engines to provide smoother power curves, eliminating the 'peakiness' of the power older strokers have. Which seems silly, I dont care about emissions! I dont care if everytime I open the throttle a mother duck and 4 of her ducklings keel over dead from pollution, I just want POWER!! I like strokers for the differences they have to 4 strokes. I don't really care that it will be a little cheaper to buy, I dont care that it will use a little less fuel, I dont care that its 'cleaner' I would prefer and old school style mental powerband, tear your arms out of its sockets stroker power band!



seconded!!

I am looking forward to riding one on the flesh though, just to check it out, but if it dont have the old stroker style power delivery, I aint gonna be buying one

So, the natural progression will be into cars if they're that good ? Be interested in what damage the AMA can do to kill this idea off. It'll be all poltics at the end of the day but ...imagine being behind the wheel of a 2stroke Ferrari when it hits the powerband .....

[tigertim20]

So, the natural progression will be into cars if they're that good ? Be interested in what damage the AMA can do to kill this idea off. It'll be all poltics at the end of the day but ...imagine being behind the wheel of a 2stroke Ferrari when it hits the powerband .....

fuck now theres a thought eh? an 8 litre v10 2 stroke ferrari with powerband. only problem is ferraris have too many wheels

[HenryDorsetCase]

the thing that really got my attention was the 600cc RS250.

yes please. How much for a kidney again?

[HenryDorsetCase]

So, the natural progression will be into cars if they're that good ? Be interested in what damage the AMA can do to kill this idea off. It'll be all poltics at the end of the day but ...imagine being behind the wheel of a 2stroke Ferrari when it hits the powerband .....

that powerband that unless you have gunfighter reflexes and balls as big as coconuts WILL HIGHSIDE YOU in the blink of an eye? Look at 80's and 90's GP footage, its absolute carnage. I'll take the big fat flat torque curve promised me by Mr Aprilia. And the light weight, and the good suspensions.