After everyone saw the patent drawing of the Ducati Elenore V8 built by Dieter Hartmann-Wirthwein, there was a lot of head scratching going on as everyone tried to visualize the engine internals in motion. I asked Dieter if he had any more images from other perspectives so he uploaded a few and, even better, the video he used at his display at Intermot. Seeing everything in motion answers a lot of questions and makes the design work look even more impressive.
Dieter also corrected one statement in the original article about the crankshaft, it’s not the original, but is a new unit machined with a 44mm hub and offset laterally so the cylinder bank is centered in the frame. He sent the above photo to show us his work. He also said the crankshaft he used in the 125cc inline 4 monkey bike was the original.
Dieter says the engine isn’t running yet, he still has quite a few pieces to complete. He is aiming for 60KW or about 80 horsepower. As I’ve already said, I am really looking forward to seeing this beautiful little V8 complete and running. Great work, Dieter!
Link: Wirthwein Motoren
Be sure to check out the video below:
UPDATE: As noted above, the 125cc Monkey bike uses the original crankshaft. Dieter confirms that the Monkey inline 4 uses the same piston and rod arrangement as the Ducati V8 project. If you’re not sure it will work, watch the video below:
Alan says
Machines are so cool.
Wave says
That is remarkable. Having ‘built’ a single-cylinder engine assembly in CAD software like this, I can definitely say that even just the effort involved in doing the drawing and animations of this engine is extremely impressive, not to mention coming up with the design and actually manufacturing it! Well done Dieter.
dan says
Down stroke efficiency and lower weight, see to be the key factors. More cylinders means more energy but with less weight friction can be reduced by slicker surfaces or bearings in those linkages! This is so simple its brilliant! As time or engine wear can you adjust tolerances or do you not have too! A rebuild would entail linkage bearing replacement or resurfacing? Wow! Cool!
Wol says
does this mean the monkey bike was also the same configuration – with one crank throw – but a four?
JR says
That’s what I’m wondering Wol.
Phoebe says
That is so wild!
Gunner says
Great engineering, but….. the thermal issues regarding those inner cylinders look a bit scary. Also, the pivots for those rockers between the cylinders look to have a hard job to survive. In fact, I really can’t see them living too long at anything like decent revs or power. But perhaps that’s not the meaning of all work involved here, showing us all it can be done seem far more important than building a mega power engine. As such, it is a superb example of German craftmanship.
B50 Jim says
I love the engineering mind. This is a great exercise in “doing something just because you can”. Can’t wait to hear it run!
As for readers worried about durability, there’s that engineering mind again. I once asked an engineer about the problem of thermal expansion in welded railroad rails. He said, “Install it so expansion isn’t a factor.” Huh? He pulled out a book and showed me some numbers for expansion in steel rail. Big numbers. But overcome those numbers and your track just sits there causing no trouble. Engineers see all problems in terms of what is necessary to solve them, not whether they can be solved. This engine will run very well. I’d love to see this done with two inline sixes.
matt g says
This is cool but since the inner and outer banks are slaved to one another, isn’t it basically a V-4? The displacement is spread out so I suppose you could rev it faster but would you want the “twinned” cylinders at different parts of the cycle?
Tyler says
Being a 4 stroke they will be on opposite strokes one will be fir in as the other is exhausting I would assume.
FREEMAN says
Pretty cool to see it in motion. Can’t wait to see it running in the metal.
Alan says
matt g, if one cylinder is on the exhaust stroke and the other is on the compression stroke (or power & intake strokes) then they would act as separate cylinders.
JR says
As for all the “doing it just because you can” comments… maybe he knows something we don’t.
I wonder if you would have to design special connecting rods (materials, shape). Normally con rods are designed to take compressive loads, not tensile loads. These con rods are going to be subjected to significantly more tensile load because the outer cylinders will be pulling the connecting rod when they go through their power stroke.
Jer says
Con rods already take significant tensile loads from the piston traveling upward then being pulled downward at TDC between exhaust and intake strokes. But it doesn’t matter. Resistance to tensile and compressive stress depends on the cross-sectional area of the rod, not the shape. Shape of the rod is only a concern in bending stress.
Champi says
Alan, how can you make the cylinders work on different strokes? Wouldn’t that make the camshaft design more complicated? Although I guess that if he has already developed the engine block and the crankshaft that would be almost easy…
Paulinator says
Hmm? Anyone pick up on the fact that the outboard pistons will have lots of dwell at TDC dwell and less at BDC? Tuning this machine will definitely be unconventional.
todd says
Since the crankshaft is not elliptical (indeed, a crankshaft can never be elliptical) the dwell will be identical at TDC and BDC.
The cam shafts will be identical to a typical SOHC inline-four, except there will be two.
As far as loading goes, the rod should not have problems, nor will any type of strut in tension, when the outboard cylinders are pulling up on it. Struts (connecting rods) are much stronger in tension than compression.
I don’t see why there are so many nay-sayers on this one; all you need is compression, spark, and fuel…
-todd
JR says
Not nay-saying, I LOVE IT!. I have checked up on this one daily since the first article came out.
B50 Jim says
Love all that monkey-motion! It’s like the rocker arms on a Chrysler 426 Hemi — movement in all directions and it all works somehow. The rods operating in tension will be no problem — it’s just like the rods in a “normal” engine.
Paulinator says
Todd,
If everything was symmetrical then the in-line four would be perfectly balanced…It isn’t. The piston spends about 1/3 of its time (120ish degrees) at or very near BDC….that’s why the in-line six is so smooooooth. I don’t see any means to change that mirror relationship in these model images that depict the walking beam, so I’m guessing that the outboard pistons in this engine will have unusually long dwell at TDC. Maybe that’s a good thing?
Wave says
matt g, having the cylinders move in this kind of way is identical to a 4 cylinder or V8 engine with a flat-plane crankshaft. This gives much better primary balance and balances moments without requiring any counterweights. In this particular engine it would be very difficult to add counterweights, which is why the flat-plane type layout is desirable.
Tom Lyons says
In my opinion, there are going to be different piston speed characteristics in the outer cylinders and inner cylinders, due to the rockers.
At the very least, the piston speed curve of the outer cylinders will be the exact opposite than the inner cylinders. So, the dwell time at BDC for the inner cylinders will be the same as the dwell time at TDC for the outer cylinders. This is due to the inverse action of the rockers.
For the pistons to not by “out of sync”, the outer pistons need to move down at the same piston speed curve as the inner cylinders move up, and vice versa.
The dwell times at TDC and BDC, as well as the piston speed curves and acceleration curves are directly related to the rod/stroke ratio, which in this case is determined by the “y-shaped” rod which operates the in inner 2 pistons.
So, I think this is going to exhibit mirrored dwell times AND mirrored piston speed curves, with the outer pistons being opposite than the inner pistons, by definition in this design.
This means that breathing is affected, because the peak piston speeds will be reached at different degrees for the inner and outer cylinders. So, camming should be different for the outers and the inners, in terms of lobe center angles and critical valve timing events.
Perhaps this may be exploited to good effects.
I’ve never had to deal with a situation like that before.
Anybody think I’m all wet with this assessment, or not?.
jumping jack stroke says
Tom – your words and the video seem to explain the ‘math’ that is going on inside that engine in terms of the rod relationships & speed.
Mule says
After watching the video a few times, I was wondering how long the outboard linkage pivots will last? Feeding combustion loads straight down into basically a side mounted lever. It looks like a couple blasts up to 10K rpm would blow those pivots right out of the bottom of the cylinder. Usually a piston transmits its loads stright down into a verticle rod and even that creates ungodly loads on big and small end bearings and an I-beam rod structure. This looks very complex and delicate. Rotating at 6 rpms in the video it’s fun to watch and fascinating to try and comprehend, but at 8-10k, there is no way I want to be standing very close to it. Ker-powie! Klank!
Peter says
Tom, the motion is an exact sinusoidal motion for both inner and outer pistons. This is exactly the same as for an normal four-cylinder engine. The forces on the pistons are different due to the different phases of the cycle, but the flywheel makes sure that the motion is constant.
Forces on the linkage bar between the inner and outer pistons are high and therefore, a high bending moment will occur. The linkage can be designed for this, so it should not be a problem.
Great piece of engineering !
Greybeard says
“Superfluous” piece of engineering I’d say.
Only 80hp output?
The Duc L- twin puts out 80 hp all on its own, why add all the power robbing extras?
“Because he can”?
That’s known as pleasuring oneself mechanically.
Tom Lyons says
Hi Peter,
Well, the piston speed curve, even in a normal engine of any number of cylinders, is not perfectly symmetrically sinusoidal.
The CRANK is sinusoidal motion as the primary component, but the cosine-effect of the connecting rod causes the additive sums of primary and secondary motions to be non-sinusoidal in result.
It’s the rod/stroke ratio that determines the final shape of the curve, due to this cosine-effect of the rod.
And so, I still think that since the outer cylinders are actuated by the inner cylinders(and their rod), that this will cause the Descending piston speed curve of the outer pistons to mimic the Ascending piston speed curve of the inner pistons, and so on.
Clearly the descending and ascending velocity curves are not the same in any engine, because of the angular vectors involved with the motion. On the descent, the crank is moving down and away, and the rod is moving down and away, until max piston speed is reached somewhere around 75*ATDC depending on the rod/stroke ratio. Not at 90*ATDC. It’s when the rod and crank have a 90-degree relationship, which occurs before the 90-degree crank angle. Then it begins to slow.
However, on the way up, the rod also reaches this same 90-degree relationship with the crank at the same ~75*, but BEFORE TDC(not after BDC).. This means that in the ascending stroke, the piston speeds are highest in the 2nd half of the stroke, and in the descent it reaches highest piston speeds in the first half of the stroke.
Now, this means that since the outer pistons in this engine are controlled by the motion of the inner pistons(via rocker linkage which causes 180* phasing), that the descending piston speed curve on the outer pistons will be the same as the ascending piston speed curve on the inner pistons.
Clearly, the ascending piston speed curve starts slower, and gains its max speed after about 105 degrees of travel, and not after about 75 degrees of travel(as the descending piston speed curve produces).
That means that the descending outer piston will not reach max piston speed until about 105″ATDC. Because it is controlled by the inner pistons and their rod to follow their motion curve on the ascent. And the ascent motion curve is different than the descent motion curve, WHEN THE ROD/STROKE RATIO IS CONSIDERED.
The outer pistons have essentially no rod/stroke ratio. They are controlled by the inner pistons, in a 180* phased relationship by the rocker linkage. They are forced to follow the motion curve of the inner pistons, in opposite phase.
So, the points that I want to be clear on, are that the piston velocity curves are NOT pure sinusoidal in ANY piston engine. They are ALWAYS affected by the rod/stroke ratio, and the peak piston speed is ALWAYS reached when the rod and crank are at 90-degree relationship, and NOT when the crank angle is 90-degrees.
And that this engine will have inner pistons that reach max velocity at around 75*ATDC(or whatever the r/s ratio dictates, which is generally around that area) on the down-stroke.
And that due to the rocker controlling the outer piston in an inverse phasing, the outer piston will not reach max piston speed until about 105*ATDC(or thereabouts), because the piston that is controlling its motion won’t reach it’s ascending max piston velocity until 105*ABDC which is 180-degrees out, where it has to be with this linkage.
So, the question would be, “How does the inner piston on the ascent make the outer piston on the descent reach max piston speed before it does, considering this linkage phasing?”
I don’t think it can.
Now, of course, I’m not saying that this will prevent the engine from “working”. I’m simply observing that the piston velocity characteristics of the outer pistons will be inverse of the inner pistons, and this affects the entire piston velocity curve of the outer pistons, which will affect the breathing characteristics for intake and exhaust, and also the torque delivery characteristics on the power stroke.
I recognize that there are a couple of very short rods in play in this rocker system which have their own angular characteristics, but they appear to only operate around a very short radius, and appear symmetrical, so I’m not sure if they really can compensate in any way for the macro behavior imparted by the main rod/stroke ratio.
If piston velocities were indeed perfectly symmetrically sinusoidal curves around the x axis, then I wouldn’t be bringing this up. But they are not. So when you invert them, things change.
If the inner piston reaches max piston speed at ~75*BTDC on the up-stroke, then the outer piston won’t reach max piston speed until ~105*ATDC on the down-stroke, because they are linked in 180-phase by the rocker. How could it be any other way?
So if that is indeed the case, which it appears to be, then the cams need to be designed to exploit this behavior, and the cams for the inner pistons will not be the ideal cams for the outer pistons.
And that is my observation and my contention.
Tom
JR says
It would seem that if you are right Tom, then yes, cams could be developed separately for the outer and inner pistons and perhaps the intake runners could be optimized separately for outer and inner piston breathing characteristics.
What do you do for a living?
JR
rohorn says
“That’s known as pleasuring oneself mechanically.”
And looking at it on the internet and talking about it is…?
Tom Lyons says
Hi JR,
I design and manufacture performance parts and modifications for vintage motorcycle engines, primarily the Royal Enfield Bullet 500 single cylinder engine.
Because of what I do, I pay particular attention to how the engine demands affect the breathing requirements, so that I can effectively create improvements in function.
I admit that this new system in the Elenor V8 is a tricky thing to analyze.
I’m always open to correction, but I think I have this piston speed thing pegged.
I’d have to calculate-in exactly how much effect those little con-rods on the rockers play into the equation before making any design decisions.
A full graph of motion, velocities, and accelerations would be needed.
Tom
Dorzok says
I don’t get it. it seams the outer piston have no action on the crank at all. they simply push the inner pistons up, either during compression or exhaust (video didn’t show ignition phase). what does this do?
David says
(matt g) says; “isn’t it basically a V-4?”
The answer is no, because in other twins, fours, sixes and eights, we also have paired pistons. Being that it is a four cycle engine, only one cylinder of a working pair of pistons has combuston in first revolution, while the other cylinder of that pair has combuston the next revolution. The valve action is 360 degrees different between cylinders of a working pair.
(Dorzok) says; “it seams the outer piston have no action on the crank at all. they simply push the inner pistons up.”
Yes they push the inner pistons, also by combustion and so in effect they provide force also to the crank by being tied into the mecanisum.
I also aggree that (Tom Lyons) is correct and I am impressed with his observation of the related piston acceleration. He is one smart engineer! Pistons do indeed stop and then start at top and at bottom dead center. Their speed usually slows, way down for several degrees before TDC/BDC and stays slow for several degrees after TDC/BDC, in a common connecting rod and crank assembly. I have heard of some engine designs that place the crank in a manner that it is not on a plumb line center, below the center of the piston, so as to vary the effect of rod trust.
Using pivot links hooked from inner pistons to outter pistons on the Ducati Elenor V8 engine, there is indeed a tricky variation to the normal piston speed at TDC and BDC, on the outter pistons!
Dorzok says
AH!! duh. so instead of pushing the crank journal they pull it. duh.
JR says
Tom, could one do this (motion analysis) with accelerometers on the bottom of the pistons? Would the engine need to be running under it’s own power (rather than being motored)? If it did, it would be hard to not destroy your accelerometers. Otherwise, I guess you could take highspeed data from a crankshaft position sensor (magnetic pickup on a disc a la ABS wheel speed sensor with high enough sampling rate).
JR
Tom Lyons says
JR,
This would usually be done by computer by plugging values into calculations and running the plot.
I think a special program would probably be needed to be written for this unusual engine.
But if you had to, you could do it mechanically, via measurement.
Tom
Chanson says
JR-the connecting rods should be just fine. While the outer pistons will be pulling the conrod during the inner pistons’ compression/exhaust phase, this is typically when the rod experiences compressive loading. So in a sense, during this phase the outer pistons will actually be reducing the stress that the rods are subjected to, and the opposite–you could use weaker rods–would be more plausible.
To answer Greybeard and the comments ‘just because I can,’ you are missing the point. Innovation is a process of taking conventional practice and asking ‘Why is this the norm? How else could this be done? Why has this never been done?’ Most of us consider our time too valuable to spend it doing something ‘just because I can,’ but rather because we believe there is a benefit to doing it differently. It’s easy to sit back and point out all the design flaws and criticize the power output, but it’s not like Ducati twins 30 years ago were putting out 80hp. It’s misguided to compare a novel design to one that’s been refined over the last couple of decades. Who knows, maybe there is an advantage to this design that will reveal itself in the coming years after it is better understood.
Tom, I think I am a little confused by your question: “How does the inner piston on the ascent make the outer piston on the descent reach max piston speed before it does, considering this linkage phasing?†I assume you mean that the outer piston ‘should’ read max v at 75ATDC but instead it reaches it at 105ATDC and you are perplexed by this notion. I think it’s pretty obvious and you will agree; since the rocker puts the outer piston out of phase by 180 degrees, that should be enough explanation right there, don’t try to over think it, but an easy way to visualize it would be to imagine an invisible rod and crankshaft connected to the outer piston. instead of pushing the piston, it pulls it, punching through the head. If you reference this imaginary rod, the piston reaches max v at 75 ATDC. I guess the short-winded explanation is that you are referencing both pistons to the same rod when they would actually be on different and OPPOSITELY oriented rods.
I agree with your assessment, I just didn’t understand the confusion. Like you pointed out, it will be interested to see how mirroring the piston’s velocity profile affects the breathing and combustion cycle.
Tom Lyons says
Chanson,
Thanks.
Yes, it was pretty much a rhetorical question, but I thank you for your interest and clarifying comments in agreement.
It’s really a fascinating opportunity to explore new design ideas.
The Kneeslider brings these things to our attention, which I would never have otherwise seen, and it is so much fun to be able to read and participate on this website. The informational resource here is amazing.
It is my favorite bike site!
Tom
Peter says
Tom, you are right. I made a calculation and plotted the cosine in as well. It showed what you wrote. I try to put the graph somewhere on the internet and show it here.
Peter says
Hereby the promised link to the piston speed graph:
https://docs.google.com/leaf?id=0By-UTLMv7fMBYjFkYmZlYWItZWMyNS00ZGM2LWI0MWYtMTI0ZmI0OTBmOGJm&sort=name&layout=list&num=50
Assumptions:
Offset in crank-shaft: 50 mm
Rod: 100 mm
David says
(Tom) and others say; It’s really a fascinating opportunity to explore new design ideas.” “The Kneeslider brings these things to our attention, which would never have otherwise be seen.”
I too, enjoy this opportunity to explore new information and become involved with the intelligent readers of this wonderful web site.
I agree that this is an amazing bike site!!!
On another note; (my 2 cents, in conclusion) I think that the traditional method of a working pair of pistons, having two connecting rods, such as in a Triumph parallel twin is superior to the strange creation, of connecting two exotic inner piston extentions, to a single rod.
The manufacter of the Elinore V8 inner pistons will be difficult and the spacing of the two cylinders becomes very close. I believe that two crank jounals, set at the same plane, (old Triumph design) surounding a flywheel/counterbalance weight, is the way to go. 180 degrees apart or other interval, as found in some parallel twin engines are alternate designs.
More over, the linkage to the outer pistons in the Ducati Elenore V8 is intriguingly different, but I suspect it is not going to be better than convetional design. That is my 2 cents, based on intuition.
Jim Kay says
Possible to fire two cyl. at the same time?It would simplify the cam timing.IDK, just my crazy mind working.lol
Thom says
Okay, I’m getting a little out of my element technically here… But to all those who are claiming this won’t work, did you catch the reference to the 125cc 4-cylinder monkey bike? It obviously uses the same principal, albeit in a smaller displacement, and it works just fine. And 80hp from a two-valve Ducati 900 is an improvement, however slight. I agree that this is just something impractical and needlessly complex, but it’s cool, and that’s as good a reason as any to make it!
kneeslider says
This discussion has been extremely interesting and the analysis by Tom is impressive. Some of you do have questions about whether it will work at all, including predictions of the engine exploding shortly after it fires up. As noted, Dieter uses the original crankshaft in the 125cc Monkey bike inline 4, and as some have wondered, is it constructed the same way as this Ducati? The answer is yes.
I asked Dieter about it and he said theory is of no use if you can’t start the engine and hear it run. The Monkey bike was a test to see if it would work as planned and it was only after he made sure everything checked out that he applied for the patent.
I’m adding the video of the Monkey bike above just in case you’ve convinced yourself it won’t work.
David says
The Ducati V8 article stated that the original 900SS crank is used. This cannot be true because the original 900SS stroke of 68 mm is too long for using with the small bore pistons in the V8. Also being that the outer pistons act to counterbalance the inner pistons there would be a reduction needed in the crank counter weights. OK, so then a new dimensioned similar crank could be made.
My father was of German ancestry (KACHELMEIER) and I observed his mechanical and scientific mind in action. However, my Mother was of Irish ancestry and I also observed her simplistic approach to doing things. I suspect that my father, like many of his kind, go out of their way to “think out of the box,” because they are creative. Many times they produce unusual tools for replacing the common hacksaw!
Many years ago there was an article in Cycle Magazine about the NSU motorcycle engine that had two out of phase connecting rods, as a drive mechanism for the overhead camshaft. When Cycle Magazine asked the designer why he went that route instead of using chains or gears as was common practice. He replied that he wanted to have mechanics open up the engine and marvel in astonishment as to how smart those Germans are!
Palmer says
does it have also Desmodromic Valves?
David says
This question was asked in he original posting of the Ducati Elenore. (kneeslider) answered this question, by saying no.
BTW; Being that there are only two rods in the center of this engine, I am wondering if there is going to be enough splash of the crankcase oil to lubricate the outside pistons and their piston pins. Some engines have squirt holes in the rods and some only have rod splashers, but either way there is only two rods in the center and non on the ends.
JR says
That little monkey bike sounds sweet!
I want that 4 cylinder 125cc on a Puch Moped cafe racer!
Loopbaanadvies says
Usually a piston transmits its loads stright down into a verticle rod and even that creates ungodly loads on big and small end bearings and an I-beam rod structure.
Pasco says
How can i get a small engine like that?
Walter says
This thread and this motor are fascinating. Thanks Tom for helping me to understand
so much more with your knowledge and excellent writing. I am no engineer but I will be very surprised to see this v8 be a viable design. I love the way out side of the box thinking but 80 hp is not so great and I just cant see this thing holding up to real life demands.
Also was it just me who thought the monkey bike sounded like it was held back in some way?
AD says
68mm stroke?
That’s 10mm more than what you find in a Ferrari 275 V-12.
A bore & stroke of 60 X 44 in a V-8 will give 1-litre – and probably a redline over 15K,
especially with Desmo valves, more with pneumatics.
satariel666 says
4 pistons against one rod? Nah for how long? Well maybe if the are made from adamantium?
Cool idea but completly useless.
M CONTI says
Amazing. If that thing runs reliably – no dammit – if that thing runs: I’d buy one.
Chris Walker says
Why not put the small end bearing in the web linking the two central pistions ? This would simplify the central pistons wishbone mounting & could allow the central webs & central pistons to be cast enbloc, so you would only need a small end bearing for the wishbone, the same as the outer pistons !
Chris says
A very interesting engineering exercise indeed. I wonder what the reaction of Ducati’s engineers would be. What I’d really like to see, though, is Ducati build a 600 thumper—perhaps half a 1198 engine?!—and fit it to a compact, lightweight scrambler type bike. Say 50 hp and plenty of low-down torque in a bike that weighs maybe 160 kg. Now that would be interesting.
HERMES CIRCELLI says
NÃO VEJO PROBLEMA ALGUM DOS CILINDROS LATERAIS ¨PUXAR¨A BIELA CENTRAL PARA CIMA. Jà VI ENSAIOS COM PARAFUSOS DE 13 mm. DE DIAMETRO AGUENTAREM 8.000Kg. ANTES DE ROMPEREM.
Ventura says
very good, how to make it,?
from Indonesia
Solomono says
Dieter . Its a good idea . For thermal issues problem , can help Nikasil or I dont know the name of a USA carbon for cylinder but they also can help your motor . You dont need Desmodronics Valves its a better idea . Coates valves . Can have high RPM.
saad says
in this way power of other two cylinders could not work properly … it will generate power like two stroke engine
VMX12Rider says
To be honest, it looks like an excessive amount of engineering to overcome the same inertial forces that a regular 4 cylinder Boxer engine would. The Pistons can now apply force to the crank through a full rotation.. just like a boxer can… as for performance wise, I’d have to see how it runs along side a regular 4 banger of equal displacement..
Brett says
Absolutely brilliant!
It seems overly complex at first but consider that with four rocker arms he has eliminated six [heavy] connecting rods and three [heavy] crank throws.
Sadly, ideas like these tend to come and go. Not because the concept is inferior but because it has to compete with over a century of refinement that the “conventional” design has endured. As mentioned, things like rod to stroke ratio and cam timing are all well know in a conventional engine, where this engine has a completely unknown arrangement on the outer cylinders. Add to that the design of the rockers; what material do you make them from, what size/shape should they be, what kind of bearings should they use? When it comes to conventional connecting rods these types of questions already have answers. You can theorize and calculate all you want but the only way to find these things out is to build it, run it till it breaks, change something then start the process all over again. That is how modern engines produce the kind of power and longevity that they do today, not necessarily because it is the better concept.
I hope that the initial tests of this engine go well enough that it is further developed. Imagine how great it could be with a bit of real world refinement.
justin_o_guy says
I sure would like to understand how the inboard pistons are built to accommodate the rod & the lever & all the necessary articulation.
I am enjoying the stuff about piston speeds, Ive been aware of them but never quite able to grasp the math. Still NOT! But I enjoy knowing someone does,,