2 stroke thread (with occasional F1 relevance!)

[gruntguru]

As for your wanting to upscale, motorcycles are (parts of the developing world - excepted) generally used by a solo rider, whether for fun, commuting, or for direct work purposes, & the small size means less space is occupied, both on road, & for parking, so I'd suggest you are perhaps over-reaching with the call for a rotor-flight car.

Motorcycle - cross rivers, mountains?
Solo flyer pilot training - where?

I think the motorcycle is (as JAW intended) a good example of the demand for single occupant transportation.

Flyer pilot training? Perhaps a high quality simulator could be produced at reasonable cost?

[J.A.W.]

As for your wanting to upscale, motorcycles are (parts of the developing world - excepted) generally used by a solo rider, whether for fun, commuting, or for direct work purposes, & the small size means less space is occupied, both on road, & for parking, so I'd suggest you are perhaps over-reaching with the call for a rotor-flight car.

Motorcycle - cross rivers, mountains?
Solo flyer pilot training - where?

I think the motorcycle is (as JAW intended) a good example of the demand for single occupant transportation.

Flyer pilot training? Perhaps a high quality simulator could be produced at reasonable cost?

Indeed gg, roads/viaducts/bridges have been a regular thing for civil-transport over such features
since before Caesar's day, but further to Pinger's claims about E-regulations, it seems self-evident
that any flying machine - with significant carrying capacity - is going to be severely use-regulated
within cities, on a basic security-level basis, whereas the damage that any solo flier can wreak, individually, is going to be limited, payload-wise, even if 'Kamikaze'-intent/remote controlled...

About the simulator, perhaps a 'passive-rotor' suit set-up, in an existing 'sky-diving simulator'
vertical-type windtunnel, may be a practicable start for Manolis' 'personal flyer?

The Wright Bros learned to fly with gliders well prior to attempting powered (contra-rotating prop)
heavier-than-air flight, quite sensibly. (& after model-tests in a windtunnel, as it happens).

[J.A.W.]

The following is an interesting design from INNengine, which they're calling a 1 stroke cycle engine. It appears to operate like a "Big Bang" or "Screamer" engine, with two cylinders mirroring a cycle, e.g firing simultaneously.:

https://www.youtube.com/watch?v=aovQguKPG4A
http://innengine.com/
http://innengine.com/home/

Ok, OO7, while this machine may be erroneously (marketing-hypewise) described as a "1-stroke",
in fact its a 2-stroke, whereas a machinegun is a 1-stroke & the bullet/piston does not 'reciprocate'!

Funnily enough however, the fairly recent 'Brane theory' by physicists attempting to figure out the
origin & 'mechanics' of our Universe have developed a scheme fundamentally identical to the O-P
2T system, reciprocation cycles & all... ('cept maybe for the staggered timing, give 'em time).

(When I was a kid, & suffering from respiratory illness, I'd thought the 'Big Bang' was probably
more likely to be a 'breathing' event, even if on a 'cosmic' scale as it happens, but like a bad
productive coughing fit, &/or attendant puking episode - at worst - but hey, who yet knows?)

[OO7]

The following is an interesting design from INNengine, which they're calling a 1 stroke cycle engine. It appears to operate like a "Big Bang" or "Screamer" engine, with two cylinders mirroring a cycle, e.g firing simultaneously.:

https://www.youtube.com/watch?v=aovQguKPG4A
http://innengine.com/
http://innengine.com/home/

Ok, OO7, while this machine may be erroneously (marketing-hypewise) described as a "1-stroke",
in fact its a 2-stroke, whereas a machinegun is a 1-stroke & the bullet/piston does not 'reciprocate'!

Funnily enough however, the fairly recent 'Brane theory' by physicists attempting to figure out the
origin & 'mechanics' of our Universe have developed a scheme fundamentally identical to the O-P
2T system, reciprocation cycles & all... ('cept maybe for the staggered timing, give 'em time).

(When I was a kid, & suffering from respiratory illness, I'd thought the 'Big Bang' was probably
more likely to be a 'breathing' event, even if on a 'cosmic' scale as it happens, but like a bad
productive coughing fit, &/or attendant puking episode - at worst - but hey, who yet knows?)

I agree that it's a two stroke, as I count a single stroke as the movement of a piston in one direction.

[Big Tea]

The need for individual personal transport of this type could vary a huge amount depending on area.

For instance, someone who lives a half mile from work but has to drive 10 miles to the nearest river crossing.
When I lived in the Welsh valleys it was a trip of 18 miles by road to get to a town less than 3 miles away on the map as all roads ran north-south linked at the end, and my trip was west-east.
My brother in somerset could not cross a road when the tide was in to go in one direction. There must be many cases where a short trip in a straight line is quite a run by road

[Pinger]

The need for individual personal transport of this type could vary a huge amount depending on area.

For instance, someone who lives a half mile from work but has to drive 10 miles to the nearest river crossing.
When I lived in the Welsh valleys it was a trip of 18 miles by road to get to a town less than 3 miles away on the map as all roads ran north-south linked at the end, and my trip was west-east.
My brother in somerset could not cross a road when the tide was in to go in one direction. There must be many cases where a short trip in a straight line is quite a run by road

That's more what I had in mind. That and the third world where roads are prone to flooding, disaster areas eg, landslides, flooding, etc, where the terrain is unstable and normal roads blocked/washed away.
Somewhere between a drone and a helicopter in capability.

I can't see the Western world permitting anything but electric propulsion in cities and towns - the drive to electrify cars and trucks has already begun.

[gruntguru]

Personal flyers will initially be recreational (and possibly military) machines only. It will take many years for them to develop the sophistication required for use as everyday transport.

As to combustion engines - we still tolerate line trimmers and lawn mowers with higher emissions than Manolis engine. Let alone the high powered recreational craft (water, air, land and snow) that still use two strokes and high emitting ones in many cases.

[Dr. Acula]

As to combustion engines - we still tolerate line trimmers and lawn mowers with higher emissions than Manolis engine. Let alone the high powered recreational craft (water, air, land and snow) that still use two strokes and high emitting ones in many cases.

True, though more and more stuff like chainsaws and trimmers go electric. Also in Europe new vehicles like motorcycles outboard motors and similar stuff must comply to Euro 4 emission standards since 2016, which is impossible to achieve for any 2 cycle engine which uses a fuel/oil mix.

[J.A.W.]

^ "Impossible" Dr.Acula?

Actually no...

As you'll see duly cited/linked, in the post quoted below.

(If I might take the liberty of quoting a relevant post of my own, from a few pages back).

Included in this fairly recent conference on 2T technical matters is an interesting
presentation of the potential for existing Rotax 2T snowcraft engines - to meet
stringent Euro-emissions regulations - while powering a road-legal motorcycle.

https://drive.google.com/drive/folders/ ... 7R1OTJQRdm

Click on file 3_3 (its located 3rd column down, 2nd from left).

[J.A.W.]

Personal flyers will initially be recreational (and possibly military) machines only. It will take many years for them to develop the sophistication required for use as everyday transport.

As to combustion engines - we still tolerate line trimmers and lawn mowers with higher emissions than Manolis engine. Let alone the high powered recreational craft (water, air, land and snow) that still use two strokes and high emitting ones in many cases.

Yeah gg, most likely there'd be restrictions on 'personal flyer' use in cities, ('cept for cops & etc).

But farmers already die/are injured - by the score in quad-bike crash incidents - so if a flyer is
available, the same farm kid who is already getting 'big air' on his MX bike, up in the 'back paddock',
will likely be pressing hard for 'a go' on a true flyer, too...

Both BRP/Evinrude E-TEC 2T DFI outboard marine engines, & KTM's TPI 2T enduro bikes meet current
Euro 4 emissions regs, (& of course, NATO/National Security Agencies, are exempt from civil-standards).

[Pinger]

As to combustion engines - we still tolerate line trimmers and lawn mowers with higher emissions than Manolis engine.

Hand held 2T have to meet pretty tough regs and prove compliance over something like 100 hours. It has led to 4T entering the market.
And, we don't at this point in time know what the emissions of Manolis's engine are.

[J.A.W.]

This recent research article describes a 2T engine capable of up to "47.2% BTE", & thus perhaps may be
the kind of thing Pat Symonds is considering (albeit breathing limited by its basic poppet valve tech).

https://www.sciencedirect.com/science/a ... 991830715X

[J.A.W.]

Here's another recent appraisal of the DFI jet-injection potential for high-efficiency/power in FIM
MotoGP racing applications & includes inherent 2T advantages of recent interest, for FIA/F1.

https://pdfs.semanticscholar.org/71d7/2 ... e41345.pdf

[Pinger]

Cheers for the two links J.A.W. Interesting.

[Tommy Cookers]

Mr Boretti's paper above seems to be wrong in some basic statements

and another poster has today expressed dissatisfaction with another Boretti paper