2 stroke thread (with occasional F1 relevance!)

[FW17]

Wonder if there are working prototypes of these

A patent drawing submitted in 2013




There is another one done in 1990, similar but still uses transfer ports. This system has quiet a lot of functions such as variable exhaust port sizing and timing.

These system will be perfect for turbo charging high intake pressures

[J.A.W.]

I'm just going through the motions trying to identify the ideal engine design for the Motoinno TS3 suspension, which has an amazing ability around corners, you can jump on the front brake midcorner and it holds its line, same with full throttle, handles better than a 250 gp bike and makes bumpy corners feel super smooth under brakes, also breaking load holds rear tyre to the ground not lifting the rear, rotating the bike. Likely this would have saved Marco SImoncelli given his accident was caused by the telescopic forkes oscalating on lean loosing grip and then regaining grip as the wheel mass rotated after riding up the circuit edge.

The TS3 reduces the weight, so a multi cylinders engine may not be needed if a high efficiency single could do, and more refined that single can be. So ideally a narrow light short, high efficient engine, a single cylinder Panigale taken to the logical extreme. If more power is needed a Presure wave supercharger could be used to improve efficiency...

Actually Muniix, since you mentioned Simoncelli, an ideal test of your chassis would be a Moto 2 race bike.

Moto 2, although it replaced 250 G.P. - has despite years of trying, been unable to better the fastest 250 lap of the
Phillip Island G.P. course - a fast, flowing, high speed natural circuit - which Simoncelli set @ 1.32.0 back in 2008...

Or, if you fitted one of these engines:
http://www.vmmotor.com/motokarove-motor ... 0-m01.html

& took it to the Isle of Man TT & set a new race record there...

[J.A.W.]

Wonder if there are working prototypes of these

A patent drawing submitted in 2013
There is another one done in 1990, similar but still uses transfer ports. This system has quiet a lot of functions such as variable exhaust port sizing and timing.

These system will be perfect for turbo charging high intake pressures

Yes FW17,
- there is ongoing interest in manifesting the self evident advantage of every piston down-stroke being a power stroke.

Who will be 1st to combine the 2T engine principle with harmonic operating efficiency?

http://www.google.ie/patents/US6065432
http://www.harmonicdrive.net/technology

( Again, Manolis may perceive something familiar in the 'harmonic drive'.)

[J.A.W.]

& a little something in metal by Kawasaki, from 'bout 40 years back...

[Muniix]

I'm just going through the motions trying to identify the ideal engine design for the Motoinno TS3 suspension, which has an amazing ability around corners, you can jump on the front brake midcorner and it holds its line, same with full throttle, handles better than a 250 gp bike and makes bumpy corners feel super smooth under brakes, also breaking load holds rear tyre to the ground not lifting the rear, rotating the bike. Likely this would have saved Marco SImoncelli given his accident was caused by the telescopic forkes oscalating on lean loosing grip and then regaining grip as the wheel mass rotated after riding up the circuit edge.

The TS3 reduces the weight, so a multi cylinders engine may not be needed if a high efficiency single could do, and more refined that single can be. So ideally a narrow light short, high efficient engine, a single cylinder Panigale taken to the logical extreme. If more power is needed a Presure wave supercharger could be used to improve efficiency...

Actually Muniix, since you mentioned Simoncelli, an ideal test of your chassis would be a Moto 2 race bike.

Moto 2, although it replaced 250 G.P. - has despite years of trying, been unable to better the fastest 250 lap of the
Phillip Island G.P. course - a fast, flowing, high speed natural circuit - which Simoncelli set @ 1.32.0 back in 2008...

Or, if you fitted one of these engines:
http://www.vmmotor.com/motokarove-motor ... 0-m01.html

& took it to the Isle of Man TT & set a new race record there...

J.A.W You worked that one out well;

The http://www.motoinno.com.au is not mine, it just happens that they come up with a similar idea, I was reading a paper on bike interlinked suspensions when a news article came up on the TS3. Similar configuration to one in the paper, but arrived at through different goals and the TS3 isn't interlinked. Have you had a read over their site, they give some decent details, being the engineers. Valentino's ex Suspension guy, Warren Willing got the suspension setup properly before he passed away. They have a downloadable data page with the analysys using a 1ms sampling telemetry of their prototype bike with a 2002 70hp Ducati Desmodue 900 air cooled vs a 2005 GSX-750r (last one before electronic aids) showing it needs near zero counter steer, and less lean angle, you just turn in and you exit one second earlier due to higher speed than the GSX, with 200 corners in a race. The riders can't believe how far they can push the bike into corners, it is eventually the rear that lets go. Sir Alan Cathcart has ridden it at Broadford racetrack in Victoria, one he has raced at many times and said none of the other 150 bikes he had ridden there had gone around the esses as fast.

They are entering the Spanish Moto2 in 2017, they already have the engine and a race team building the bike and rider. It takes more than a good chassis to do well, but if they get the rest of the bike competitive and setup well, the ts3 will likely get banned, going on history.

The best article from an ex racer doing a proper test ride at Lakeside racetrack is here;
http://bikereview.com.au/motoinno-ts3-h ... er-review/
A quote
"Arriving at the first turn at Lakeside I initiated the turn at what I thought would be the appropriate tip-in point for a motorcycle – the TS3 responded so quickly that I almost cut the grass on the inside of the uphill right hander. The next time around I increased my speed and moved my turn-in point later, something that usually doesn’t go hand in hand – again it was too tight. It wasn’t until the second session that my brain fully comprehended how tight an arc the TS3 can hold.

Tip-in is fast and accurate, mid-corner front-end stability is solid and the line doesn’t widen as you twist the throttle on the 900cc V-twin – which is complemented by an explosive bark out of the two shorty mufflers.

In fact not even applying quite a handful of front brake while leaned over (yes I did run a little wide on one corner) – something I would never do on a conventional front-end didn’t unsettled the TS3 or widen its radius – If I had done that on my race bike I would have no doubt tucked the front.

[Tommy Cookers]

@ J.A.W
your photo looks rather 1939ish DKW
my local dealer had one on display, the company owned by Stan Hailwood (whose son Mike won 9 WCs)
DKW made these 'split singles' (2 power piston/1 charging piston) like your photo, even 4 power piston versions
and a 4 power piston car engine till 1940
maybe there were military or industrial versions possibly transferred in WW2 ?

btw that PC Vincent (of Vincent motorcycles) was active in radical 2 stroke design in the 60/70s - maybe there's patents around ?
iirc he did a super efficient 2 stroke late in WW2 for an air-droppable lifeboat

the Harmonic Drive - what value is zero backlash in a vehicle transmission ?
I tried quite hard to use the thing 25 years ago, but it's only needed or valuable in about one in a thousand applications
there's always reasons why the conventional is the conventional (people with 'unique' products never have a useful range of product available)
I used c.o.t.s throughout, a 5 kW Scott-wound transformer, a precision ballscrew, 'AC' (synchronous) servo motor(/generator) and drive etc ....
total cost about $2000, and as a side effect, arguably better energy recovery than current F1


about vibration - remember Mr Duckworth said the DFV had more vibrational force from the valves than from its flat crankshaft
presumably the rotary valves are better in this regard
and the 2 stroke with poppet or rotary valves can incorporate a balancing function into the valve drive
rotary valves (having more c.s area than poppet valves) presumably for road etc use need VVT or similar

'TJI' techniques or not, the scope for lean running is quite small with liquid fuel, ie the boost will be lower than with gas fuel
we should always consider 'tuned' induction and exhaust functionality even with eg mechanical or electric supercharging
high boost ultra lean gas engines seem to use all their turbine power for supercharging ie have no recovery potential despite their use of backpressure


btw (NOTE TO SELF)
Manolis' view that the crossplane crank eg Yamaha is not lighter than the flat crank I fwiw now accept
my instinctive view otherwise was based on my 2004 idea that Yam's MotoGP was some odd '3 main bearing' style - less web, so lighter
remember thousands of races won by F3 and BTCC Cosworth-Ford UK pushrod 105E 3 main bearing engines with 81mm pistons running to 12000 rpm

[Muniix]

@ J.A.W
looks rather 1939ish DKW
my local dealer had one on display, the company owned by Stan Hailwood (whose son Mike won 9 WCs)
DKW made these 'split single' (2 power piston/1 charging piston versions) like your photo, even 4 power piston versions
and a similar 4 power piston car engine till 1940
maybe there were military or industrial versions ?

btw that PC Vincent (of Vincent motorcycles) was active in radical 2 stroke design in the 70s - maybe there's patents around ?

the Harmonic Drive - what value is zero backlash in a vehicle transmission ?
I tried quite hard to use the thing 25 years ago, but it's only needed or valuable in about one in a thousand applications
there's always reasons why the conventional is the conventional (people with 'unique' products never have a useful range of product available)
I used a (custom) 5 kW Scott-wound transformer, a (c.o.t.s) precision ballscrew, 'AC' (synchronous) servo motor(/generator) and drive etc ....
total cost about $2000, and as a side effect, better energy recovery than current F1


about vibration - remember Mr Duckworth said the DFV had more vibrational force from the valves than from its flat crankshaft
presumably the rotary valves are better in this regard
and the 2 stroke with poppet or rotary valves can incorporate a balancing function into the valve drive

'TJI' techniques or not, the scope for lean running is quite small with liquid fuel, ie the boost will be lower than with gas fuel
we should always consider 'tuned' induction and exhaust functionality even with eg mechanical or electric supercharging
high boost ultra lean gas engines seem to use all their turbine power for supercharging ie have no recovery potential despite their use of backpressure


btw (NOTE TO SELF)
Manolis' view that the crossplane crank eg Yamaha is not lighter than the flat crank I now accept
my view otherwise was based on my 2004 idea that Yam's MotoGP was some odd '3 main bearing' style - having less web it would be lighter
remember the thousands of races won by Cosworth-FordUK pushrod 105E 3 main bearing engines turning 81 bore pistons up to 12000 rpm

If one were optimising engine losses then piston side thrust force would be the #1 issue to reduce, being the majority of fmep.
The dual counter rotating crank helps here, cancelling out the side thrust forces ( lateral reactive forces), reducing liner wear and gas blow by, helping oil longevity. Typically piston skirt friction is 0.1-0.6 bar from 1 to 6 krpm, or 50-60% of fmep at high rpm where fmep can exceed 2.3 bar at 15krpm.
The TJI does provide complete and fast combustion, with higher lambda's increasing the HA10,50 and 90 times and decreasing NOx by up to 99.7%. It will require a large increase in intake flow/reduced throttling losses. It also supports increasing compression ratio's 1-2 points.
The Gas fuels you are refering to is liquid petroleum gas? Due to the Polytropic index ?
High compression ratio's, generally prefer rotary valves, as knock is never observed.
Thermal barrier coatings on selected combustion surfaces could help, provided they have short thermal lag and durable.
High speed engines really need to have internal aerodynamic optimisation (3d cfd ?) same with oil churning losses.

I'm not convinced having essentially a small seperate combustion chamber as in the PatRoVa that opens up into the main combustion chamber as the piston descends from tdc, the partially burned gas (5-10% at most) will be expanding into a larger area, its the same compression volume moving into the same expanding main volume, but i'm sure the combustion will be effected differently as it has a different chamber shape and greater surface area, it will be forced to expand faster to fill the new volume, loosing heat, slowing combustion, and maybe even creating areas that won't reach combustion temperature, this was identified in the cfd combustion analyses (20krpm i think) on the Bishop RV engine and in those two exact spots there was carbon buildup occuring on the head surface, due according to the cfd data to excess squish velocity causing quenching, dealt with by studing squish behavior in this chamber and guidelines for optimising squish zones and spark plug location. Otherwise the engine will be very dirty emissions wise. Their is always a chance that as the gas is compressed into the compression volume and ignited, that the moles get over energised and just spin rather than bumping into one another which creates the kinetic energy/heat for combustion, if i've got my combustion physics right.

[J.A.W.]

Curious to see mention of Mike Hailwood & Warren Willing in recent posts, I'd met them when I was a kid,
Mike lived just down the road from me after he retired from McLaren Racing, & he was always an affable bloke.

Likewise, Warren always had an interest in trying out new developments, & worked for Kenny Roberts & KTM
on engine development in their G.P. efforts - before 2Ts were banned.
See below for something he tried ~35 years ago, putting his championship winning Kawasaki superbike 2T 750 engine into a Yamaha TZ G.P. roadrace chassis for an endurance race. ( scroll down a bit to find it.)
http://www.deejay51.com/coca_cola_800_gallery.htm

(Actually Muniix, one of those Kawasaki 750 triple mills might make a good basis for your machine, they are
fairly light ( ~55Kg) capable of good power ( ~120hp) of simple construction , & yet would readily showcase innovative modernisation schemes, of the type shown in the research paper on a snowmobile on the previous page.)

2T combustion chambers unencumbered by poppet valves offer optimal design opportunity for discretionary placement of injector/sparkplug for stratified charge burn & flow-squish characteristics... (as noted by the
previously referred to 'jet ignition' research paper- linked back on page 66).

[Tommy Cookers]

If one were optimising engine losses then piston side thrust force would be the #1 issue to reduce, being the majority of fmep.
The dual counter rotating crank helps here, cancelling out the side thrust forces ( lateral reactive forces), reducing liner wear and gas blow by, helping oil longevity. Typically piston skirt friction is 0.1-0.6 bar from 1 to 6 krpm, or 50-60% of fmep at high rpm where fmep can exceed 2.3 bar at 15krpm. ........
...... The Gas fuels you are refering to is liquid petroleum gas? .......

it's a shock to see a dual crankshaft single
checking the early Lanchester car (a 'rhombic drive' 360deg parallel twin without primary or secondary vibration) ....
the Lanchester patent (1898) does not even mention its cancellation of piston side thrust

(some ?) production vehicles now have anti-friction coatings, better lubrication than the 1998 Supermonos ?, NA F1 even had anti-friction fuel
so would the dual crankshaft single justify its extra weight and bulk (and extra bearing friction) today ? (I wonder)
granted the high rpm adds to this part of friction - proportional to bmep the fmep will be higher NA than boosted
multi cylinders somehow seems more plausible

regarding gas fuels -
for reasons of chemistry LPG goes much leaner than gasoline, methane leaner than LPG, and hydrogen much leaner than methane
with or without TJI
maybe current F1 fuel is designed to give best lean running ?

anyway, imo there's a big difference between NA and boost for leaning in its various forms

[Muniix]

If one were optimising engine losses then piston side thrust force would be the #1 issue to reduce, being the majority of fmep.
The dual counter rotating crank helps here, cancelling out the side thrust forces ( lateral reactive forces), reducing liner wear and gas blow by, helping oil longevity. Typically piston skirt friction is 0.1-0.6 bar from 1 to 6 krpm, or 50-60% of fmep at high rpm where fmep can exceed 2.3 bar at 15krpm. ........
...... The Gas fuels you are refering to is liquid petroleum gas? .......

it's a shock to see a dual crankshaft single
checking the early Lanchester car (a 'rhombic drive' 360deg parallel twin without primary or secondary vibration) ....
the Lanchester patent (1898) does not even mention its cancellation of piston side thrust

(some ?) production vehicles now have anti-friction coatings, better lubrication than the 1998 Supermonos ?, NA F1 even had anti-friction fuel
so would the dual crankshaft single justify its extra weight and bulk (and extra bearing friction) today ? (I wonder)
granted the high rpm adds to this part of friction - proportional to bmep the fmep will be higher NA than boosted
multi cylinders somehow seems more plausible

regarding gas fuels -
for reasons of chemistry LPG goes much leaner than gasoline, methane leaner than LPG, and hydrogen much leaner than methane
with or without TJI
maybe current F1 fuel is designed to give best lean running ?

anyway, imo there's a big difference between NA and boost for leaning in its various forms

The dual crankshafts eliminates the counter balance saving that weight, and each crankshaft is sharing the load so can be optimised reducing their individual weight, which further reduces the stresses so more weight can be saved. The total load they share will be higher at identical engine load with the reduced piston frictional losses. If you favour the increased fuel efficiency that makes it more worthwhile. It also rotates the rotational asymetry 90 degrees, which provides a nearly 5% improvement in gas pressure conversion to rotational torque, due to the more favourable crank/rod angle over cylinder pressure curve, which when combined with the TJI could be further optimised. The compression stroke is typically 170 degrees, and the last 90 degrees before tdc is the highest piston speed imparting more energy into compression and exhaust enthalpy which could be used by energy recovery even a pressure wave supercharger, they are pretty cool.
Put in some real-time physics modelling into the engine control, along with one of the new cylinder only pressure sensors that provides pressure data at 15 khz are cheap now, could make a very efficient thermodynamic cycle. Their are also advantages in the power/intake stroke (in 4T) which is typically 190 degrees, giving more rotational duration for Intake and blowdown. These advantages all add up. Combining a bishop rotary valve, tji, cylinder pressure sensor and dual counter-rotating crankshafts with a clever physics based engine control all kind of help each others features.

The new 64 bit ARM SoC's have 8 cores, and 96-512 gpu cores, these are good for Partial differental equation crunching.

[J.A.W.]

Muniix, plainly, you are on the wrong thread for attempting to 'sell' 4T merits..
4Ts are inherently 'lazy' - a condition that can only be ameliorated by significant cost & complexity...

[Muniix]

Muniix, plainly, you are on the wrong thread for attempting to 'sell' 4T merits..
4Ts are inherently 'lazy' - a condition that can only be ameliorated by significant cost & complexity...

While I've only initially been considereing 4T the unique motion of the offset crankshaft is also suitable to 2T to those who
think about it. The offset creates 4 quatrants of different piston motion, due to the angle of the conrod in each of the four quadrants, four stages in an ICE thermodynamic process. Alot of what i've said is similarly applicable. I spent an hour today looking into how this would work with a 2T implementation.

Yes, I was realising this, should've asked how to branch off to another thread.

A further optimisation on the 2T process is achieved in the aformentioned Pressure Wave Supercharger, effectively makeing a 1T process, this has been the subject of a lot of research at Michigan State University. Instead of just using the exhaust gas energy to compress the intake air using gas dynamics, to make a super efficient supercharger with near zero lag, they incorporate the combustion into the process as well, and eliminate the real inefficient part, the piston engine. Called a Wave Disk engine.

[J.A.W.]

Yeah Muniix, no offense, but you ought to know that 'bout 3/4's of a century ago..
Hitler's scientists had got such pulse tech worked out,
& this was adapted - post-WW II for 2T expansion chambers...

Here's a 1947 Allied translation of the original Nazi work.. which had gone into cruise-missiles bombarding London...

http://naca.central.cranfield.ac.uk/rep ... m-1131.pdf

[J.A.W.]

& presenting..

Drum Charger...

http://www.alterego-hardware.com/images ... CMA-EN.pdf

[Muniix]

& presenting..

Drum Charger...

http://www.alterego-hardware.com/images ... CMA-EN.pdf

I saw that they use them on the KTM390's, to mildly boost them. Its uses a membrane, good way to make it cost effective. It's by using some high speed compute power you can really get PWS to work well in boosting ICE engines. They need two throttle's valves, a gas pocket valve and exhaust angle valve all controlled by some clever software. Boosting helps improve efficiency and a PWS works well with small engines, software doesn't have much weight and can help achieve huge gains in efficiency, and maximise energy and reduce emissions/by products. current engines are approaching 50% efficiency any design that comes close is worth persuing. Any modern engine development would have to exceed 40% thermal efficiency.
The RMIT Hydrogen Direct Injection, Jet Ignition engine paper is where I first learned about the Patakon engines, and how I ended up here.