Ring longevity is controlled by clean conditions and by the piston not rocking in the bore . As it is a rough surface albeit far from true abrasives, it does wear the ring. This is less consequential if the ring is square with the walls. Design is taller than if you have a conventional rod assembly, with more recip mass, and friction with the lower guide shaft. This is offset greatly by a reduction in crankcase volume, as well as more efficient scavenging as the ports can provide swirl, and more than any design possible with conventional piston port/reeds /timed rotating disc valves and attendant friction and propensity to fall in systems over complex. Now I see one with freevalve tech, and cute little turbo with fuel and MW50
Wow! Amazing. Not the engine noise I was expecting. I am not convinced with the all including electric vehicle movement. Believe in repair, repurpose and recycle. But not at the expense of all current vehicles and as you have shown the inventiveness of clever people to redefine current technology. Best thing I have seen in ages. Cheers
Awesome! Needs a turbo though because you are throwing away energy! Edit to add: This was the first video on the channel that I watched, I've seen that a turbo has been added! I can't wait to see the results! Subscribed and Bell button selected!!!
I've just come across this RUclips clip. I think this is a brilliantly thought out & carried through concept, It cracks 2 problems fundamental to the 2 stroke engine. 1:- Separation of crank lubrication from the induction system. 2:- removing oil from the petrol there by vastly reducing pollution. And putting cream on the cake, unidirectional scavenging. I take my hat off to you sir.
Neither of these two ideas are new. Both have been used in production 2 stroke engines quite a long time ago. I am not saying it isn't cool and very well executed. And it may contain little ideas here and there that are indeed new. But fundamentally the separating of the oil and gas has been done. Why no expansion chamber? Is the exhaust valved? and if so how?
@@jeffreywagner1084 An expansion chamber is not needed as the exhaust valve timing is determined by the cam lobes rather than having a port that is open on the way up as well as the way down as in the conventional design which needs one to combat the symmetry of the port timing.
I made something similar out of a briggs & stratton. Used both valves for exhaust, fixed lobe and 1:1 cam drive. Then ported cyl like a detroit diesel and added a small supercharger..
@@krazed0451 yea the old Detroit diesels where 2 stroke. Very similar in function to his design but they used a screw type super charger on all models and some had a turbo as well to cram the charge into the cylinder threw transfers and the exhaust was cam and valve it relied on the intake air charge from the blower to push the exhaust out when the valves and transfers where open at the same time. Notice in some of his other videos he is changing the design to get more area under the piston which he needs more under it. A lot more that's why he did the turbo imo. The engine needs a blower you can't get enough charge up to the top because of what gets trapped in the transfers
I have a few questions. So I'm assuming you're using the exhaust valves like a uniflow engine, so the intake valves are just sealed/closed? I noticed you machined the cams, but didn't heat treat them afterwards? Do you have any drawings etc I could look at? Have you put any load on this engine above 50%? What ring/liner combo did you use? Do you have an email address I can contact you through?
It uses all four valves as exhaust valves, short duration so can only get limited valve lift in that duration. Cams are carburised and hardened to 62rc. I used a blank cylinder liner and machined them from that.
Hi Matt he said in another comment that compression rings don't have to be lubricated and therefore aren't. But don't they have to ride on a thin oil film? I mean metal to metal contact would very quickly wear down the rings wouldn't it???
Tricky..Well done. Is the ex vaive closed on the way up? Are you using all valves as exhaust? and whats the open intake port timing? I guess the top & bottom hold oil and 2 stroke in the middle. yes your rings need lube.
@Daan Daan Yes, designer confirmed that on another posting. Thought this config(2:1) would have maintained the standard (260°??) opening duration but obviously lobes have been reprofiled. Expect lift would be considerably less on a short duration profile. This is a very interesting implementation :)
@Daan Daan In another posting David mentioned he was planning to reduce the size of the inner bore rod which would require a new con rod . I pointed out (in my response to the cam gearing) that, even if the piston rod is 25% of the main bore diameter, this is only around 6% of the total cylinder volume. Reducing it would be subject to law of diminishing returns. As this is a direct injection system, the fuel (fully vaporised) would occupy around 14% volume at stoichiometric ratio so (in theory!) total cylinder filling could exceed 100% (94% transfer then 14%) providing no scavenging losses . In practice, (he is using 180° valve duration but not symmetrically, the piston will pump out a fair volume before exhaust valve closure.
@Daan Daan Just rechecked video and it looks like rod is around 50% of bore diameter which equates to 25% of total volume so perhaps this is worth reducing. Not so much of an issue with the turbo version.
Remove reminds me of the 500 twin 2 stroke Norton made with the stepped piston. The larger lower half being the compressed of the inlet charge that was feed to the smaller top half of piston for the power stroke. Think they called the motor the wolf. Basically a super charge system.
It looks like a hard sleeve or anodizing on the shaft below the piston where it goes through the bearing/seal. It wouldn't be hard to get a good pressurized supply to that area but how is the wear going after a year? There are some sad people commenting and showing their ignorance. Did you do any CFD with the swirl in the cylinder? I would have thought colliding streams which then rose together but I suppose that could leave burnt gas adjacent to the cylinder walls unscavenged. So many variables and very interesting.
The sleeve is 4130 steel, and the rings are SG iron, so are compatible. I see the injector spray pattern on the top of the piston, showing me that the piston is probably being cooled a little by that.
It didn't make sense at first, then I had to go back to your CAD design video and understand the whole concept. The intake ports become the transfer ports by the time the piston reaches BDC, brilliant. The fuel is cylinder port injected, nice. The piston has 2 friction areas, one of them being the stem of the mushroom. You have addressed that too, by oil injection. And the repurposed 4 exhaust ports on the head, what can I say, I'm lost for words. I have one question, is the oil burn, much less compared to a traditional two stroke? Do you still have to use 2 stroke oil?
@@algiecompositeaircraft5629 Do keep a small quantity of 2T oil handy in the bike. If you do encounter something that feels like a piston bind, immediately pour that 2T oil into the tank. It will save your engine for the day. Get back, open up the engine, inspect yourself, analyse and troubleshoot. You've put a lot of hard work, I'd be gutted to see it ruined. Cheers.
Wow that sounds amazing the head would flow brilliantly with all valves being exhaust..Is the cam chain pocket part of the transfer porting? It's kinda hard to see.
I was going to say awesome, unfortunately that does not come close to covering it. Officially at a total loss for words just wow. Is there a reason this does not have the expansion pipe?
Thank you for the compliment. It does not need an expansion chamber because it does not have adjacent exhaust and transfer ports, the exhaust valves and transfers are separated by distance and pressure wave. Exhaust should be similar to a four stroke, tuned length mostly.
Hold up, is that a double exhaust system? If so, why? Please explain, im very interested. And I cant see any smoke, are you running a particular two stroke mix, or have you found a way to do regular unmixed 95, in a two stroke?! I have waited forever for the day, when you can use the mechanically simple two stroke concept, without having to run a fuel mix - it will revolutionize EVERYTHING! And it just gave me an idea - please consider it. You know those small engines; Predator, Tillotson whatever, they have a sump and scoop for oiling the crank and piston bearing. Could you theoretically take the concept of the mushroom piston in one, close of lubing the top, slap on the EFI and make a "pure" 2 stroke without valves?
David, interesting concept and a lot of work. I do not see anything patentable though. You use the stepped piston concept of the Ryger engine combined with a Uniflow cylinder as used by many diesel two-stroke engines. It will always have a delivery ratio quite a bit less than 1.0, unless you are boosting it. I fail to see any new concept unless you are doing something new with the injection system.
Hi Neels. My Mushroom Piston engine design is quite different from the engine you describe, and yes, I use a much different combination of components and shapes in a different manner to that engine. I do not claim the uniflow port design. I do claim the injection system methods as well, yes. From a critical observation of the Ryger engine, that design has port exhaust, making it require an expansion chamber, mine does not, and the delivery ratio on that engine is very poor, and without a major redesign which would invalidate it's European patent, could not increase on that delivery ratio. Thank you for your concern though.
Hi Niels, no, Ryger did this is a different, far inferior way, and my patent will show my claims to be just that, you will just have to wait for that to be released, but again, thanks for the concern!!
What's the reason for the pocket in the piston's rod? I would have thought you want to reduce the dead volume in the compressor side to force more air into the combustion chamber and more fully evacuate the compressor side for the next cycle's charge Overall though, it sounds smooth and has no noticeable smoke. Great fabrication work, especially for the equipment available!
I wanted the piston assembly to be the same weight as the stock piston, so had to lighten it here and there. All design is in Solidworks, and the SW generated weight from the solid model came out exact.
If you see the transfer port area, this is compressive volume, that i wanted to keep small, as you say. But there has to be a trade off against flow from the reed valve area, and enough flow from under the piston, back through the transfer slots in the liner, and into the upper part of the slots as they are uncovered at the edge of the piston. All a balance of flow versus intake compression.
@@algiecompositeaircraft5629 yeah, my error, sorry, i saw your other video where we see the all the internal parts and just realise there was a lower piston part sliding to prevent that. Sorry and very nice work, cant wait to see the dyno run
I am interested to know more, I am a paramotor pilot and the biggest deal is the motors, they suck. What are the benefits to your engine and what sort of power to weight ratios do you expect to see?
A simple paramotor two stroke is very simple, but can be problematic as you know. My design is more complex, in normally aspirated mode will have higher power to weight of a simple port two stroke, but no emission issues with fuel oil mixing. With a turbo it will have a much higher power to weight ratio, but even more complex. Longer life than a port two stroke though.
@@algiecompositeaircraft5629 interesting, currently I have a 30hp 220cc motor, it weighs about 31lbs. You think your engine could be lighter and more powerful as well as more reliable, if that is the case I can insure you cn sell an ton of engine lol, all the people I know would want one
@@algiecompositeaircraft5629 I would be willing to test something out. I am a big dude so I need a big motor. If your claims are true you would change the sport forever and I would love to help you make that happen as that is the biggest issue in the sport right now, the motors.
A company here in NZ, Autoflight, makes 800cc twin cylinder engines complete with reduction gear. They have been used in autogyros and possibly other things. Lightweight and plenty of power
I'm not convinced about the intake compression volume. The displacement under the piston is a lot less than above and it only compresses from the underside of the piston until the transfer ports open. There's also a fairly large volume in the intake manifold and transfer ports. So I can't see it fully scavenging. I think you need a blower.
Yes, which is why, in my next video, you see i added a turbo. Two strokes rarely, if ever, are able to use a turbo, port exhaust types, this causes high back pressure that does not work well, also piston face heat, and siezures. Also, like the Detroit diesel two stroke that has no pumping function other than the blower, they will not start with a turbo. My design gets around those two stroke shortcomings. Is also why my work on it now is to design and build new connecting rods for a smaller lower cylinder, for a better pumping ratio.
@@algiecompositeaircraft5629 How about Koenigsegg´s Valvetrain for some individual rpm-based valve-timing. Here, a cheap effort with 3D-Printed casing ruclips.net/video/E9KJ_f7REGw/видео.html You should make also a video with an explanation, I understand only uniflow... All the rest is like chinese to me... ;-) Do u use all the valves? do u use all of them for the exhaust? If u put an electronic valvetrain in, and tune it, it´s gonna be my dream-engine... ;-) Here, also a bit of lecture on scavenging, but this engine is relatively slow... www.semanticscholar.org/paper/Experimental-investigation-of-CAI-combustion-in-a-Zhang/756530470de6c52989e8a6d5d333941c4c106479
Very interesting! I think i get the concept. I read in the comments that you dont mix oil in the fuel. I can see how the bottom of the piston gets lubricated from the crank case. But i dont understand how the piston rings in the top part of the piston get lubrication. Can you explain this? Or is it not neccesary in this design? Great engineering! Very impressive
The oil rings are stationary, in the base guide bore, and are reverse rings, they seal on their inner diameters. The compression rings see the same lubrication as a 4 stroke, fuel only. If even a half drop reached the compression rings in a 4 stroke per cycle, you would have huge oil burn problems. Modern 4 strokes have zero oil reaching the compression rings, the oil rings stop that.
@@algiecompositeaircraft5629 I think that there are many engine designers that will argue the statement of no lubrication to the compression rings in a 4 stroke engine. I have worked on aka rebuilt engines of all sizes gasoline and diesel 2 and 4 stroke for over 45 years and can tell you any engine that does not get lubrication to the cylinder and rings will not last long
@@algiecompositeaircraft5629 I work as a ships engineer. Even our relative low speed two strokes needs lubrication to the rings or we will be replacing rings and liners way to often. Before college I was an automotive technician and I can tell you that there is no way that the top compression ring runs dry as that would mean metal to metal contact. Oil film might be thin, but it is there. However cool build :)
@@algiecompositeaircraft5629 Matt from the dirty garage guy channel is working on a Hudson/Hossack engine design. I really would like to know your thoughts on that.
Thanks. I will develop a new connecting rod design, mainly, the wrist pin type, possibly moving to a one piece rod and wrist pin, and then change the pistons to use those. This will gain efficiency.
Nice build, but it's not applicable for a patent, it's an already multiple times build type of engine. How about the wear of the seal to the crankcase, it's the flaw of this kind of engine, because of the small area under the piston the pressure tends to get very high on that seal. It will work in combination with the exhaust valves, as shown but isn't durable for long time. If you wat to get this working over long time you need to get rid of the bottom seal and use a hardened sleeve on the bottom part of the piston and rings like on your piston in the sleeve where it runs through.
And your comments are based on your own testing of a similar type of engine i assume? I have learned a lot with this so far, and honestly, none of your thoughts are based on reality i have seen.
While a very interesting design in some aspects most of those principles have been done before with stepped pistons. The mushroom idea is ok but will have a much lower volume in the pumping chamber than the combustion chamber reducing efficiency. I had presumed you were going to fit a blower when i first saw the design!
Is why the connecting rod wrist pin design is important, this improves efficiency. What i have done here was an adaptation to an existing engine, proof of concept, so it has shortcomings that an all new engine would not have.
@@algiecompositeaircraft5629 very cool. If I had the resources I would definitely be interested in the files, also very awesome that you are making this available to those that do have the resources!
8 exhaust valves into 4 exhausts, yes. Shorter duration equals the need for more exhaust flow in shorter times, opening the exhaust valves sooner so there is higher residual pressure to flow faster.
@@dirtygarageguy 4 stroke 'compression' rings see virtually no oil, if any gets past the oil rings, the engine will burn oil. I have fuel closer to the compression rings than the typical 4 stroke does.
@@detslutarmed standard hone. Fuel is injected in the cylinder wall directly, aids in piston cooling and cylinder lubrication. A typical four stroke has no oil on the compression rings, none make it past the oil rings, so same applies here.
Just make it a two stroke diesel, small blower, no carbs, no ignition, high efficiency. Better yet a Commer knocker style opposed piston diesel on a bike
Looks like a double acting marine diesel engine. Or is that part below the piston for scavenging? This is more than 100 years old. Or what part is your novel intellectual property?
The volume below the piston head is the scavenging pump... Marine diesels use a roots types blower and have no self scavenging built in, they won't run without the blower.
So, after all this intriguing effort, why did you not use true schnurle porting, rather than some odd version of, and no tuned pipes either? Heresy I tell ya!!! And yes... a ball bearing turbo can easily be bolted on a 2-stroke, and it will build extreme power. How do I know? I built a fully turbo'd twin cylinder 2-stroke before it ever fell into favor by snowmobilers. Everyone said it couldn’t be done… au contraire! Blown (supercharged) 2-strokes? Nope... all you get is a cleanly scavenged engine with a LOT of unburnt fuel "blown" right out the exhaust. This is because the pressurized crankcase is completely open from carb, through the crankcase, through the transfers, across the piston head and right out the exhaust port while at BDC. No pressure is ever stored anywhere, just a cleanly scavenged cylinder and exhaust... which can be worth a little extra HP, but not much, and at the expense of much higher fuel consumption (as high as twice as much fuel burn). BUT... a turbo partially blocks the exhaust port, preventing unrestricted transfer of fuel/air mixture to the atmosphere, storing that pressurized mixture in the exhaust pipe between the port and turbo, which is then ignited at the next exhaust port opening, burning and adding even more pressure and higher EGT's to the turbine, spinning that wheel (and the attached compressor) even faster, providing a cascade of ever increasing boost. It's a never ending cycle (until fuel exhaustion) which I've called "Inter Chamber Burning”. This method rapidly builds boost to a very high level… so much so that if a waste gate is not attached to keep that boost under control, a holed piston will instantly result (and sometimes, much worse). After a little more thinking, you can easily see where the turbo can eventually out-power the crankshaft (if it had a gearbox tied to the turbo), and all the piston and crankshaft become is an N1 "Gas Producer". Eliminate the crankshaft and piston altogether to create a constant burning combustion chamber that's fed by the pressurized fuel and air from the turbo compressor wheel, with the hot gas powering the turbine wheel, and you have a complete turbine engine. Which is very much how the turbine engine was invented in the first place. Interesting stuff…
Answer to your first part, schnurle porting is only needed when you have an exhaust port to deal with. This has no exhaust division issues like a regular port two stroke.
Secondly, this is far different from a port two stroke in regards to the need for an expansion chamber. No adjacent ports, good separation of exhaust and transfer by pressure wave, and asymmetrical exhaust timing. Don't forget, this is not a clean sheet design; i had to work around the existing cylinder studs and timing chain well.
Sounds very cool indeed. I would wonder that since the "transfer passage" is through the crankcase (via the reed valve), and still fills the cylinder as does a conventional transfer, and if the exhaust cam timing is long enough... through some type of overlap between the multiple "transfers", would a tuned pipe still function with whatever pulse wave may still exist? Or, is this a type of uniflow transfer design where the transfer passages have no overlap with the exhaust valve/s? Either way, a turbo would still likely work, and should work well even with complete separation of functions. Food for thought...
Of course they have overlap, the same as a tuned four stroke does, sort of, so need the same exhaust as a four stroke, a tuned length. Might be noted that some four strokes benefit from some sort of resonance chamber, like the ones used on 450 MX engines.
Same parts as a 4 stroke has, no more, but its a 2 stroke, without the shortcomings a normal 2 stroke has. No oil or smoke in the exhaust, asymmetrical exhaust timing that a convent 2 stroke cannot have, much better "crankcase" compression ratio, better intake flow path.
@@algiecompositeaircraft5629 I realise this, I build unconvetional twostrokes also. Uniflow Opposed Piston, petrol mostly. I use a piston instead of valves, here first start up 25 years ago .ruclips.net/video/BPr694nlUKE/видео.html
Valves system must be a restriction to ultimate rpm traveling at engine rpm? You are fairly restricted to open time. I see, second look, double lobes, half engine revs, not a lot of lift?
Yet gas flow passed through two exhaust valves on a 4 stroke is ok? This is twice the flow area. Seems like you are really here commenting to advertise your own efforts.
I guess if ever there was a case for free valve technology, this is it. Im not intetested in commercializing my stuff, it just for my own play. Good luck with your venture. And certainly I will keep my thoughts to myself.
Basically this is a derivative of a 2 stroke diesel engines used into ships, but running on gas, isn't it? But while in diesel naval engines there is top cylinder lubrication (with special oil that burns and goes into the exhaust) here there's no lubrication for the compression piston rings. And this is definitively going to make it to fail very quickly. Just check at wankel Mazda engines: same problem with their "blades", and Mazda has access to much more exotic materials and material engineers than you, and much more to gain from a reliable rotary engine which has been a very distinctive mark for them for lot of years, as like as desmodromic distribution is for Ducati, and nevertheless they didn't manage to make it reliable and took it out of production years ago (last was on RX8). And no, 4 stroke engines have oil into the honings of the cylinder, so it's definitively not correct to say they run "dry". Nice realization but definitively no reliable usage for this.
You do realize that the top rings see no, zero oil, in a modern 4 stroke, right? Modern engines burn zero oil, imagine how much they burn if even a microscopic amount gets burned in one cycle. No, the oil rings stop the compression rings from seeing any.
@@algiecompositeaircraft5629 that's simply not true. The top ring sees oils going down the cylinder as the oil ring remove the EXCESS of oil and not ALL the oil. And oil stays into the honing. Try to run ANY 2 stroke engine with no oil (which is what your engine does) and let me know in how many hundreds of meters you'll get seized engine.
Well, i have a 40k mile Toyota, and i beg to differ, it uses zero oil. How many engine cycles has it travelled in those 40k miles, to use none, don't know.
@@algiecompositeaircraft5629 self induction design point? No idea what that is. I'm saying its a copy of a uniflow system from a marine 2T design. What does this idea offer? All the complexity of still needing a valve train & all the issues with scavenging not fully filling the combustion chamber of a 2T? lol I have an improvement suggestion - put another valve in the head for intake!
BAHHAHA How are you oiling the cylinder? Premix still? How does that work with the injector washing it off? So you'll be replacing top ends as much as a regular 2T but you have the valve train to mess with every time & what you have oil pumped to the valves & plane bearing but no way to properly lubricate the rings.
@@algiecompositeaircraft5629 I can see how your design works from your cad. What I am saying still stands that this is a Bad Design. Your loss. So sorry.
Sigh. Unobservant of you to miss the point that large two stroke diesels do NOT have a self pumping feature, and are dependent on a blower to start and run. Five points for your efforts though. Buh bye.
sorry with out dyno figures it is a total waste of time, i would bet you are making less power than a 250cc 4 stroke, with little or less torque, and dry comp rings won't last one dyno run, ,t will shit it self
I have no idea what got better than the original engine but I love the fact that you test and work towards your ideas !! Great craftsmanship ...
Ring longevity is controlled by clean conditions and by the piston not rocking in the bore . As it is a rough surface albeit far from true abrasives, it does wear the ring. This is less consequential if the ring is square with the walls. Design is taller than if you have a conventional rod assembly, with more recip mass, and friction with the lower guide shaft. This is offset greatly by a reduction in crankcase volume, as well as more efficient scavenging as the ports can provide swirl, and more than any design possible with conventional piston port/reeds /timed rotating disc valves and attendant friction and propensity to fall in systems over complex.
Now I see one with freevalve tech, and cute little turbo with fuel and MW50
Wow! Amazing. Not the engine noise I was expecting. I am not convinced with the all including electric vehicle movement. Believe in repair, repurpose and recycle. But not at the expense of all current vehicles and as you have shown the inventiveness of clever people to redefine current technology. Best thing I have seen in ages. Cheers
Your machine skills are amazing, Sir.
Awesome! Needs a turbo though because you are throwing away energy!
Edit to add: This was the first video on the channel that I watched, I've seen that a turbo has been added! I can't wait to see the results!
Subscribed and Bell button selected!!!
my mind has been blown. amazing engine build.
I've just come across this RUclips clip.
I think this is a brilliantly thought out & carried through concept,
It cracks 2 problems fundamental to the 2 stroke engine.
1:- Separation of crank lubrication from the induction system.
2:- removing oil from the petrol there by vastly reducing pollution.
And putting cream on the cake, unidirectional scavenging.
I take my hat off to you sir.
Neither of these two ideas are new. Both have been used in production 2 stroke engines quite a long time ago. I am not saying it isn't cool and very well executed. And it may contain little ideas here and there that are indeed new. But fundamentally the separating of the oil and gas has been done. Why no expansion chamber? Is the exhaust valved? and if so how?
@@jeffreywagner1084 An expansion chamber is not needed as the exhaust valve timing is determined by the cam lobes rather than having a port that is open on the way up as well as the way down as in the conventional design which needs one to combat the symmetry of the port timing.
@Alfred Wedmore essentially limiting the engines rpm to half due to valve float
I made something similar out of a briggs & stratton. Used both valves for exhaust, fixed lobe and 1:1 cam drive. Then ported cyl like a detroit diesel and added a small supercharger..
yeah i was thinking the only way you can make this feasible., is to have forced induction as there is no crank charging as per a normal 2 stroke,
I SPOSE he's relying on the piston shape to force charging limited value , and lack of adequate combustion charge
I see you've found something else to keep you busy. Nice work Dave.
This is incredible! Thanks for sharing, this should have a Million views
Aww thank you!
At least...........
Compared to stroke-stuffing channel.....this engine and was made with speed of light ......AND RUNS.....
So very impressive...I want one! 🇭🇲❤️
Great engineering, love it
❤🙏
I truly hope that the patent what's the very last thing that you did. Not the other way around sure. Good luck
And they say two strokes are dead.. They're brains, perhaps. We'll done, sir!
The opposed piston engine is also a great two stroke design, more efficient and lower emissions
Looking good im amazed
So he made a Detroit diesel that supercharges itself with the down travel of the piston pretty cool
So, uh, a 2 stroke?
(It certainly is cool.)
@@krazed0451 yea the old Detroit diesels where 2 stroke. Very similar in function to his design but they used a screw type super charger on all models and some had a turbo as well to cram the charge into the cylinder threw transfers and the exhaust was cam and valve it relied on the intake air charge from the blower to push the exhaust out when the valves and transfers where open at the same time. Notice in some of his other videos he is changing the design to get more area under the piston which he needs more under it. A lot more that's why he did the turbo imo. The engine needs a blower you can't get enough charge up to the top because of what gets trapped in the transfers
@@bobbyratliff3349 Thanks for the explanation, much appreciated :-)
It’s like a Detroit Diesel uniflow scavenging but the piston itself acts like the blower very clever
Amazing for sure.
I have a few questions. So I'm assuming you're using the exhaust valves like a uniflow engine, so the intake valves are just sealed/closed?
I noticed you machined the cams, but didn't heat treat them afterwards?
Do you have any drawings etc I could look at?
Have you put any load on this engine above 50%?
What ring/liner combo did you use?
Do you have an email address I can contact you through?
Hi, yes, email me at aca at iquest.net
It uses all four valves as exhaust valves, short duration so can only get limited valve lift in that duration. Cams are carburised and hardened to 62rc. I used a blank cylinder liner and machined them from that.
Hi Matt he said in another comment that compression rings don't have to be lubricated and therefore aren't. But don't they have to ride on a thin oil film? I mean metal to metal contact would very quickly wear down the rings wouldn't it???
Tricky..Well done.
Is the ex vaive closed on the way up? Are you using all valves as exhaust? and whats the open intake port timing?
I guess the top & bottom hold oil and 2 stroke in the middle. yes your rings need lube.
@Daan Daan Presume cams operate 2x normal gearing as opening duration must be 120° maximum.
@Daan Daan Yes, designer confirmed that on another posting. Thought this config(2:1) would have maintained the standard (260°??) opening duration but obviously lobes have been reprofiled. Expect lift would be considerably less on a short duration profile. This is a very interesting implementation :)
@Daan Daan In another posting David mentioned he was planning to reduce the size of the inner bore rod which would require a new con rod . I pointed out (in my response to the cam gearing) that, even if the piston rod is 25% of the main bore diameter, this is only around 6% of the total cylinder volume. Reducing it would be subject to law of diminishing returns. As this is a direct injection system, the fuel (fully vaporised) would occupy around 14% volume at stoichiometric ratio so (in theory!) total cylinder filling could exceed 100% (94% transfer then 14%) providing no scavenging losses . In practice, (he is using 180° valve duration but not symmetrically, the piston will pump out a fair volume before exhaust valve closure.
@Daan Daan Just rechecked video and it looks like rod is around 50% of bore diameter which equates to 25% of total volume so perhaps this is worth reducing. Not so much of an issue with the turbo version.
Remove reminds me of the 500 twin 2 stroke Norton made with the stepped piston. The larger lower half being the compressed of the inlet charge that was feed to the smaller top half of piston for the power stroke.
Think they called the motor the wolf. Basically a super charge system.
Yes, similar yet different
That is insane!!
It looks like a hard sleeve or anodizing on the shaft below the piston where it goes through the bearing/seal. It wouldn't be hard to get a good pressurized supply to that area but how is the wear going after a year? There are some sad people commenting and showing their ignorance. Did you do any CFD with the swirl in the cylinder? I would have thought colliding streams which then rose together but I suppose that could leave burnt gas adjacent to the cylinder walls unscavenged. So many variables and very interesting.
Damn. Just watched the new video, all explained.
The sleeve is 4130 steel, and the rings are SG iron, so are compatible. I see the injector spray pattern on the top of the piston, showing me that the piston is probably being cooled a little by that.
Matt from the dirty garage guy channel is working on a Hudson/Hossack engine design. I really would like to know your thoughts on that.
Sell a kit? I want to do this to my bike!
Is it making way more power now?
It really sounds great, how is it performance wise?
I guess you’ll never know
Maybe some day, he will update
@@bmint maybe
Do you have a patent number?
It didn't make sense at first, then I had to go back to your CAD design video and understand the whole concept. The intake ports become the transfer ports by the time the piston reaches BDC, brilliant.
The fuel is cylinder port injected, nice. The piston has 2 friction areas, one of them being the stem of the mushroom. You have addressed that too, by oil injection.
And the repurposed 4 exhaust ports on the head, what can I say, I'm lost for words.
I have one question, is the oil burn, much less compared to a traditional two stroke? Do you still have to use 2 stroke oil?
It just uses the four stroke oiling and no additional oil added. Some say the upper compression rings need oil, i have not seen that need so far.
@@algiecompositeaircraft5629
Do keep a small quantity of 2T oil handy in the bike. If you do encounter something that feels like a piston bind, immediately pour that 2T oil into the tank. It will save your engine for the day. Get back, open up the engine, inspect yourself, analyse and troubleshoot.
You've put a lot of hard work, I'd be gutted to see it ruined.
Cheers.
@@algiecompositeaircraft5629 Of course they need oil. Even the best compression rings still glide on a small amount of oil film.
Wow that sounds amazing the head would flow brilliantly with all valves being exhaust..Is the cam chain pocket part of the transfer porting? It's kinda hard to see.
I am impressed!
I was going to say awesome, unfortunately that does not come close to covering it. Officially at a total loss for words just wow. Is there a reason this does not have the expansion pipe?
Thank you for the compliment. It does not need an expansion chamber because it does not have adjacent exhaust and transfer ports, the exhaust valves and transfers are separated by distance and pressure wave. Exhaust should be similar to a four stroke, tuned length mostly.
truly amazing.
Hold up, is that a double exhaust system? If so, why? Please explain, im very interested.
And I cant see any smoke, are you running a particular two stroke mix, or have you found a way to do regular unmixed 95, in a two stroke?!
I have waited forever for the day, when you can use the mechanically simple two stroke concept, without having to run a fuel mix - it will revolutionize EVERYTHING!
And it just gave me an idea - please consider it.
You know those small engines; Predator, Tillotson whatever, they have a sump and scoop for oiling the crank and piston bearing.
Could you theoretically take the concept of the mushroom piston in one, close of lubing the top, slap on the EFI and make a "pure" 2 stroke without valves?
Thanks. Go look at my other video showing the solid model, yes, it does not use premix fuel.
@@algiecompositeaircraft5629 You, Sir, need to get hold of Allen Millyard ASAP.
A collaboration between you two would yield a dream come true.
Sounds great, love it!
How is the upper part of the piston being oiled?
Fuel
Spectacular. I love it.
Brilliant one off
David, interesting concept and a lot of work. I do not see anything patentable though. You use the stepped piston concept of the Ryger engine combined with a Uniflow cylinder as used by many diesel two-stroke engines. It will always have a delivery ratio quite a bit less than 1.0, unless you are boosting it. I fail to see any new concept unless you are doing something new with the injection system.
Hi Neels. My Mushroom Piston engine design is quite different from the engine you describe, and yes, I use a much different combination of components and shapes in a different manner to that engine. I do not claim the uniflow port design. I do claim the injection system methods as well, yes. From a critical observation of the Ryger engine, that design has port exhaust, making it require an expansion chamber, mine does not, and the delivery ratio on that engine is very poor, and without a major redesign which would invalidate it's European patent, could not increase on that delivery ratio. Thank you for your concern though.
Hi Niels, no, Ryger did this is a different, far inferior way, and my patent will show my claims to be just that, you will just have to wait for that to be released, but again, thanks for the concern!!
There is always something patentable. If it makes sense to patent it, that is an other story.
What's the reason for the pocket in the piston's rod? I would have thought you want to reduce the dead volume in the compressor side to force more air into the combustion chamber and more fully evacuate the compressor side for the next cycle's charge
Overall though, it sounds smooth and has no noticeable smoke. Great fabrication work, especially for the equipment available!
I wanted the piston assembly to be the same weight as the stock piston, so had to lighten it here and there. All design is in Solidworks, and the SW generated weight from the solid model came out exact.
to reduce the dead volume, he can always put 2 3d-printed plastic lids on the sides of the pocket.
If you see the transfer port area, this is compressive volume, that i wanted to keep small, as you say. But there has to be a trade off against flow from the reed valve area, and enough flow from under the piston, back through the transfer slots in the liner, and into the upper part of the slots as they are uncovered at the edge of the piston. All a balance of flow versus intake compression.
Very impressive, the only thing i can see being a problem is the piston will wear out very fast and will flip in a near future...
....and you know this how?
@@algiecompositeaircraft5629 yeah, my error, sorry, i saw your other video where we see the all the internal parts and just realise there was a lower piston part sliding to prevent that. Sorry and very nice work, cant wait to see the dyno run
Okay how much would it cost to make my 500 the same?
Are you crazy, great job !!
I am interested to know more, I am a paramotor pilot and the biggest deal is the motors, they suck. What are the benefits to your engine and what sort of power to weight ratios do you expect to see?
A simple paramotor two stroke is very simple, but can be problematic as you know. My design is more complex, in normally aspirated mode will have higher power to weight of a simple port two stroke, but no emission issues with fuel oil mixing. With a turbo it will have a much higher power to weight ratio, but even more complex. Longer life than a port two stroke though.
@@algiecompositeaircraft5629 interesting, currently I have a 30hp 220cc motor, it weighs about 31lbs. You think your engine could be lighter and more powerful as well as more reliable, if that is the case I can insure you cn sell an ton of engine lol, all the people I know would want one
@@algiecompositeaircraft5629 I would be willing to test something out. I am a big dude so I need a big motor. If your claims are true you would change the sport forever and I would love to help you make that happen as that is the biggest issue in the sport right now, the motors.
A company here in NZ, Autoflight, makes 800cc twin cylinder engines complete with reduction gear. They have been used in autogyros and possibly other things. Lightweight and plenty of power
I'm not convinced about the intake compression volume. The displacement under the piston is a lot less than above and it only compresses from the underside of the piston until the transfer ports open. There's also a fairly large volume in the intake manifold and transfer ports. So I can't see it fully scavenging. I think you need a blower.
Yes, which is why, in my next video, you see i added a turbo. Two strokes rarely, if ever, are able to use a turbo, port exhaust types, this causes high back pressure that does not work well, also piston face heat, and siezures. Also, like the Detroit diesel two stroke that has no pumping function other than the blower, they will not start with a turbo. My design gets around those two stroke shortcomings. Is also why my work on it now is to design and build new connecting rods for a smaller lower cylinder, for a better pumping ratio.
@@algiecompositeaircraft5629 How about Koenigsegg´s Valvetrain for some individual rpm-based valve-timing. Here, a cheap effort with 3D-Printed casing ruclips.net/video/E9KJ_f7REGw/видео.html You should make also a video with an explanation, I understand only uniflow... All the rest is like chinese to me... ;-) Do u use all the valves? do u use all of them for the exhaust? If u put an electronic valvetrain in, and tune it, it´s gonna be my dream-engine... ;-) Here, also a bit of lecture on scavenging, but this engine is relatively slow... www.semanticscholar.org/paper/Experimental-investigation-of-CAI-combustion-in-a-Zhang/756530470de6c52989e8a6d5d333941c4c106479
Very interesting! I think i get the concept. I read in the comments that you dont mix oil in the fuel. I can see how the bottom of the piston gets lubricated from the crank case. But i dont understand how the piston rings in the top part of the piston get lubrication. Can you explain this? Or is it not neccesary in this design? Great engineering! Very impressive
The oil rings are stationary, in the base guide bore, and are reverse rings, they seal on their inner diameters. The compression rings see the same lubrication as a 4 stroke, fuel only. If even a half drop reached the compression rings in a 4 stroke per cycle, you would have huge oil burn problems. Modern 4 strokes have zero oil reaching the compression rings, the oil rings stop that.
@@algiecompositeaircraft5629 I did not know that. Thank you for your explanation. And thank you for sharing this project!
@@algiecompositeaircraft5629 I think that there are many engine designers that will argue the statement of no lubrication to the compression rings in a 4 stroke engine. I have worked on aka rebuilt engines of all sizes gasoline and diesel 2 and 4 stroke for over 45 years and can tell you any engine that does not get lubrication to the cylinder and rings will not last long
@@algiecompositeaircraft5629 I work as a ships engineer.
Even our relative low speed two strokes needs lubrication to the rings or we will be replacing rings and liners way to often.
Before college I was an automotive technician and I can tell you that there is no way that the top compression ring runs dry as that would mean metal to metal contact.
Oil film might be thin, but it is there.
However cool build :)
@@emilrundqvist3209 I thought the cylinder honing holds small amounts of oil while reducing the area the rings actually touch the cylinder...
does it ignite under the piston to? and above it works like a 4 stroke?
No, the lower chamber is similar to the crankcase a port two stroke has, it creates an induction pump. Head is a four valve exhaust type.
It is exquisite work. have you thought about trying a turbo? I think that mechanics setup is perfect to support it
See my other video for that
@@algiecompositeaircraft5629 Matt from the dirty garage guy channel is working on a Hudson/Hossack engine design. I really would like to know your thoughts on that.
@@EbonyPope I didn't find that video, can you add a link please?
@@algiecompositeaircraft5629 This is the second part. Just go through his videos you'll find the other. ruclips.net/video/fMrsGf4Gv4A/видео.html
@@algiecompositeaircraft5629 This here is the latest with an interesting modular design. ruclips.net/video/LvgYwwJS9gg/видео.html
F N brilliant
Good job there, what is next move with the technology?
Thanks. I will develop a new connecting rod design, mainly, the wrist pin type, possibly moving to a one piece rod and wrist pin, and then change the pistons to use those. This will gain efficiency.
One lil start up that’s it
Nice build, but it's not applicable for a patent, it's an already multiple times build type of engine.
How about the wear of the seal to the crankcase, it's the flaw of this kind of engine, because of the small area under the piston the pressure tends to get very high on that seal.
It will work in combination with the exhaust valves, as shown but isn't durable for long time.
If you wat to get this working over long time you need to get rid of the bottom seal and use a hardened sleeve on the bottom part of the piston and rings like on your piston in the sleeve where it runs through.
And your comments are based on your own testing of a similar type of engine i assume? I have learned a lot with this so far, and honestly, none of your thoughts are based on reality i have seen.
Excellent video but without good narration only true nerds will understand most of it.
I mean neat, but specific power numbers? BSFC?
I have never put it on a dyno, proof of concept for a patent is the main goal
While a very interesting design in some aspects most of those principles have been done before with stepped pistons. The mushroom idea is ok but will have a much lower volume in the pumping chamber than the combustion chamber reducing efficiency. I had presumed you were going to fit a blower when i first saw the design!
Is why the connecting rod wrist pin design is important, this improves efficiency. What i have done here was an adaptation to an existing engine, proof of concept, so it has shortcomings that an all new engine would not have.
@@algiecompositeaircraft5629 actually lower c
volume cause higher crankcase compression
Love the sound! High and tight.
How much would it be to duplicate this engine?
Expensive as a prototype, but i do have the cnc programs etc.
@@algiecompositeaircraft5629 very cool. If I had the resources I would definitely be interested in the files, also very awesome that you are making this available to those that do have the resources!
2 piston 4 exhaust??
8 exhaust valves into 4 exhausts, yes. Shorter duration equals the need for more exhaust flow in shorter times, opening the exhaust valves sooner so there is higher residual pressure to flow faster.
What will you call this bike?
because it’s no longer a cheap ninja, it’s now some crazy 2 stroke wolf dressed in sheep’s clothing
How does this work without Piston skirts that prevent the Piston from kinking? 🤯
I BET IT IS NOT WORKING PROPERLY - NOT FOR LONG ANYWAY
Look again, the lower part of the piston is used as a guide.
Piston rings are lubed by pre-mixed fuel?
Compression rings only see air and fuel, this engine does not use or need an oil premix. Oil rings see engine oil only.
@@algiecompositeaircraft5629 "Compression rings only see air and fuel" - and that's why you engine is going to die.
@@dirtygarageguy 4 stroke 'compression' rings see virtually no oil, if any gets past the oil rings, the engine will burn oil. I have fuel closer to the compression rings than the typical 4 stroke does.
@@algiecompositeaircraft5629 you lose your crosshatch gets shiny cylinder walls. Nothing that binds oil film, they go dry and then goodbye
@@detslutarmed standard hone. Fuel is injected in the cylinder wall directly, aids in piston cooling and cylinder lubrication. A typical four stroke has no oil on the compression rings, none make it past the oil rings, so same applies here.
Wow!
2 stroke?
Yes.... Yes it is.
HOW DO YOU LEAR HOW TO DO THIS???
48 years of studying, and experimenting with some really nice racing equipment and aircraft design.
Can we use ur prints to make one??
If you have a CNC 3 axis mill and CNC lathe, i guess
Do you have a blog I can follow?
Really only on here. I will start putting more videos up shortly, also bring them over from my old channel
@@algiecompositeaircraft5629 Just watching the machining was incredible. I dream one day of being able to machine out my own engine parts!
I stand gob-smacked !
Interesting concept but this goes way beyond the piston
Just make it a two stroke diesel, small blower, no carbs, no ignition, high efficiency. Better yet a Commer knocker style opposed piston diesel on a bike
and the piston weight will seriously limit any ability to rev, and would guess it will hand grenade on any real dyno pulls
Guess again. It has seen 8k rpm, and the pistons weigh exactly the same as the original EX500 pistons, to a gram. But thanks for playing though!
Looks like a double acting marine diesel engine. Or is that part below the piston for scavenging? This is more than 100 years old.
Or what part is your novel intellectual property?
The volume below the piston head is the scavenging pump... Marine diesels use a roots types blower and have no self scavenging built in, they won't run without the blower.
So now the Chinese have it. Good job.
Should i..... Keep it a secret?
So, after all this intriguing effort, why did you not use true schnurle porting, rather than some odd version of, and no tuned pipes either? Heresy I tell ya!!!
And yes... a ball bearing turbo can easily be bolted on a 2-stroke, and it will build extreme power. How do I know? I built a fully turbo'd twin cylinder 2-stroke before it ever fell into favor by snowmobilers. Everyone said it couldn’t be done… au contraire!
Blown (supercharged) 2-strokes? Nope... all you get is a cleanly scavenged engine with a LOT of unburnt fuel "blown" right out the exhaust. This is because the pressurized crankcase is completely open from carb, through the crankcase, through the transfers, across the piston head and right out the exhaust port while at BDC. No pressure is ever stored anywhere, just a cleanly scavenged cylinder and exhaust... which can be worth a little extra HP, but not much, and at the expense of much higher fuel consumption (as high as twice as much fuel burn).
BUT... a turbo partially blocks the exhaust port, preventing unrestricted transfer of fuel/air mixture to the atmosphere, storing that pressurized mixture in the exhaust pipe between the port and turbo, which is then ignited at the next exhaust port opening, burning and adding even more pressure and higher EGT's to the turbine, spinning that wheel (and the attached compressor) even faster, providing a cascade of ever increasing boost. It's a never ending cycle (until fuel exhaustion) which I've called "Inter Chamber Burning”. This method rapidly builds boost to a very high level… so much so that if a waste gate is not attached to keep that boost under control, a holed piston will instantly result (and sometimes, much worse).
After a little more thinking, you can easily see where the turbo can eventually out-power the crankshaft (if it had a gearbox tied to the turbo), and all the piston and crankshaft become is an N1 "Gas Producer". Eliminate the crankshaft and piston altogether to create a constant burning combustion chamber that's fed by the pressurized fuel and air from the turbo compressor wheel, with the hot gas powering the turbine wheel, and you have a complete turbine engine. Which is very much how the turbine engine was invented in the first place. Interesting stuff…
Answer to your first part, schnurle porting is only needed when you have an exhaust port to deal with. This has no exhaust division issues like a regular port two stroke.
Secondly, this is far different from a port two stroke in regards to the need for an expansion chamber. No adjacent ports, good separation of exhaust and transfer by pressure wave, and asymmetrical exhaust timing. Don't forget, this is not a clean sheet design; i had to work around the existing cylinder studs and timing chain well.
Sounds very cool indeed. I would wonder that since the "transfer passage" is through the crankcase (via the reed valve), and still fills the cylinder as does a conventional transfer, and if the exhaust cam timing is long enough... through some type of overlap between the multiple "transfers", would a tuned pipe still function with whatever pulse wave may still exist? Or, is this a type of uniflow transfer design where the transfer passages have no overlap with the exhaust valve/s?
Either way, a turbo would still likely work, and should work well even with complete separation of functions. Food for thought...
Of course they have overlap, the same as a tuned four stroke does, sort of, so need the same exhaust as a four stroke, a tuned length. Might be noted that some four strokes benefit from some sort of resonance chamber, like the ones used on 450 MX engines.
Look at "Bolnes engine" 2 stroke marine diesel with a crosshead that is a scavenging piston with a bigger dia.
Why the valves, springs, guides, keepers, followers, camshafts? So many parts. Gas flow past four open exhaust cant be good.
Same parts as a 4 stroke has, no more, but its a 2 stroke, without the shortcomings a normal 2 stroke has. No oil or smoke in the exhaust, asymmetrical exhaust timing that a convent 2 stroke cannot have, much better "crankcase" compression ratio, better intake flow path.
@@algiecompositeaircraft5629 I realise this, I build unconvetional twostrokes also.
Uniflow Opposed Piston, petrol mostly. I use a piston instead of valves, here first start up 25 years ago .ruclips.net/video/BPr694nlUKE/видео.html
Valves system must be a restriction to ultimate rpm traveling at engine rpm? You are fairly restricted to open time. I see, second look, double lobes, half engine revs, not a lot of lift?
Yet gas flow passed through two exhaust valves on a 4 stroke is ok? This is twice the flow area. Seems like you are really here commenting to advertise your own efforts.
I guess if ever there was a case for free valve technology, this is it.
Im not intetested in commercializing my stuff, it just for my own play. Good luck with your venture.
And certainly I will keep my thoughts to myself.
How much would this conversion cost me?
Its a lot of work, so, is expensive as a prototype.
@@algiecompositeaircraft5629 I want one,
are you planning mass production and selling diy kits?
@@bmint i do not have plans to produce these, but will license the design to someone to manufacture them in larger amounts
very much alike to ryger engine
Yeah, but no, its not. Thanks for the concern though!!
ruclips.net/video/eEO8oLkhIbk/видео.html
Link to a video walk around of the turbo intercooled version of this design.
Rd350 sound
Basically this is a derivative of a 2 stroke diesel engines used into ships, but running on gas, isn't it?
But while in diesel naval engines there is top cylinder lubrication (with special oil that burns and goes into the exhaust) here there's no lubrication for the compression piston rings. And this is definitively going to make it to fail very quickly. Just check at wankel Mazda engines: same problem with their "blades", and Mazda has access to much more exotic materials and material engineers than you, and much more to gain from a reliable rotary engine which has been a very distinctive mark for them for lot of years, as like as desmodromic distribution is for Ducati, and nevertheless they didn't manage to make it reliable and took it out of production years ago (last was on RX8).
And no, 4 stroke engines have oil into the honings of the cylinder, so it's definitively not correct to say they run "dry". Nice realization but definitively no reliable usage for this.
You do realize that the top rings see no, zero oil, in a modern 4 stroke, right? Modern engines burn zero oil, imagine how much they burn if even a microscopic amount gets burned in one cycle. No, the oil rings stop the compression rings from seeing any.
@@algiecompositeaircraft5629 that's simply not true. The top ring sees oils going down the cylinder as the oil ring remove the EXCESS of oil and not ALL the oil. And oil stays into the honing. Try to run ANY 2 stroke engine with no oil (which is what your engine does) and let me know in how many hundreds of meters you'll get seized engine.
Well, i have a 40k mile Toyota, and i beg to differ, it uses zero oil. How many engine cycles has it travelled in those 40k miles, to use none, don't know.
Sounds angry! =)
2 stroke marine diesel
So you completely miss the self induction design point then, and that two stroke marine diesels always have to have a blower.....?
@@algiecompositeaircraft5629 self induction design point? No idea what that is. I'm saying its a copy of a uniflow system from a marine 2T design.
What does this idea offer? All the complexity of still needing a valve train & all the issues with scavenging not fully filling the combustion chamber of a 2T? lol
I have an improvement suggestion - put another valve in the head for intake!
If you really do not understand how this design works, then it's your loss. So sorry.
BAHHAHA How are you oiling the cylinder? Premix still? How does that work with the injector washing it off? So you'll be replacing top ends as much as a regular 2T but you have the valve train to mess with every time & what you have oil pumped to the valves & plane bearing but no way to properly lubricate the rings.
@@algiecompositeaircraft5629 I can see how your design works from your cad. What I am saying still stands that this is a Bad Design. Your loss. So sorry.
That's not new. 80%of all cargo ships are using similar engine. But for pointless engine you got skill.
Sigh. Unobservant of you to miss the point that large two stroke diesels do NOT have a self pumping feature, and are dependent on a blower to start and run. Five points for your efforts though. Buh bye.
Pay attention on words! Similar not same.
Sounds a cross between a 4 stroke and a Wankel 🤔
Yes, it has a different sound to it for sure, close to a 4 cylinder 4 stroke yet not the same.
sorry with out dyno figures it is a total waste of time, i would bet you are making less power than a 250cc 4 stroke, with little or less torque, and dry comp rings won't last one dyno run, ,t will shit it self
with 4 stroke flywheel it would build revs like a sleeping public servant