Will BLOW Up the Competition! Seriously! 

Thanks for watching! Many have suggested a typical uniflow setup with valve(s) in the head. Must admit this is tempting, and could actually make the design simpler too. Must think about it👍 Edit: I think exhaust STA could be a limitation with poppet valve in head.

this guy will not stop until he makes 100+hp 50cc engine I need determination like that

I grew up in the 80s with the RD350 as my dream bike. I used to take two-stroke tuning books out of the library, port my engine, and watch Kevin Schwantz tame the wild beasts, when the other kids were just taking the baffles out of their 50cc exhaust pipes to make them louder, and adding fairings to make them look cooler. I was therefore quite excited when I found your channel a few years back, and have been looking forward to you making the two-stroke engines that I grew up with more efficient and well-tuned. I have to admit that now I am fairly disappointed that you've given up on two-stroke resonance and actual tuning that was the most exciting thing about two-strokes to me, but I understand the pressure you've put yourself under now to deliver something.

That is one hell of a piece of engineering my friend... I am intrigued.. The idea of having the whole of both chambers filled with fuel really caught my imagination.. The potential for good and bad results really draw one into this project.. good luck, be safe.. I think you possibly have something here.. Carry on...

He had thought constipation and now he pooped out a brilliant idea. How relieved he must feel.

Innovation starts with I. One day you can say, “I did this, I made it happen.”

nothing but love. ideal transfer designs prevent intake charge mixing with exhaust, complete evacuation, no inert gases robbing power. you're not worried about short circuiting intake charge, so no need for an expansion chamber pipe, it's not a concern dumping charge out the exhaust in the quest for making power. what i am thinking is exhaust short circuiting to the transfers, both intermixing (dilution) and possible preignition from pressure difference. i suggest going halfway with sufficient blowdown times to partially evacuate the spent charge before transfers open. with proper closing timing (asymmetrical) of the rotary exhaust, you will minimize lost charge. number one rule of transfer design, don't cross the streams.

Have you ever thought about building an engine based on the Napier Deltic opposed piston. The exhaust ports are opened before the intake for better scavenging, and have direct injection.

Ferrari tried this on a three cylinder two stroke, they used a camshaft with exhaust valves not sure why they dropped the program but it probably had to do with emission.

I don't think this concept will work but it is a step in the right direction. The fuel air mixture will get pumped into the exhaust duct and then sealed off by the piston, then it will get ignited in the exhaust. Also the rotary valve will leak allot. How about an overhead poppet valve, with an athena direct injection fuelling. That will allow a wet sump too which will be a more reliable bottom end.

you could go for fuel injection integrated in the cylinder head. that way you could start the fuel injection after the exhaust port closes, which would prevent pouring unburned fuel/air mix into the exhaust cavity inside the cylinder, which could ignite when the exhaust port opens and possibly do some damage, especially if the mixture burns down the transfers towards the blower. this is as you probably know the way diesels inject fuel into the cylinder, except they do it at the time of ignition. with this you could inject far earlier and get more then enough fuel directly into the bore before spark. you could also play with inducing swirl to the charge air (like they also do with diesels) to improve mixing by doing some magic to the transfer angels, though i'm not sure of the effectiveness at higher RPM. Just an idea i got when watching the video, great work btw!

You'd need a sprung pop off valve in that exhaust to prevent backfires exploding the head. Blown V8s have them on top of the inlets, 100+ psi sprung plates

The distance-volume between exhaust port and rotary valve must be minimum to gain compresion and prevent mixture loss, the rotary also fat to widstand the temps. Also look the Koenigsberg free valve system, it may fit the idea,. I had the same idea but with a turbo after the rotary valve.

Was just reviewing the last video. (prior to this one) You need a one piece ring my friend. That pin hole is in the most stressful area of the ring. The flexing of the ring is causing it to stress fracture. The fact that it hasn't grabbed any of the cylinder is proof of that. The first failure was grabbing the cylinder on the upstroke. I suspect from too small of a ring gap ,or the exhaust port growing into the cylinder as it warmed up. Your piston design would work perfectly with a one piece ring. Or perhaps better with one of my other designs. We need to talk. I can get you there. Cheers Fred

A very clever idea. I shall enjoy following this. Good luck and thanks for keeping us entertained. Top man.....

Getting the balance right between pressures is the problem. The exhaust pressure filling the all of the ports and having the charger push against that could be an issue. I'd fit a dump valve in the manifold just to make sure you don't pop something on your first try. And try and get some live pressure readings.

I am by no means a 2 stroke expert, but a couple of things jump out at me ..... You say 4 identical inlets ..... but the inlet port on the blower side will get most of the action and the one nearest the exhaust the least! Would it not make sense to reduce the size of the one and increase the other (the two center ones could stay the same. Rotating the ports 45 degrees may also give an improvement. Most 2 strokes have an improved burn if you have turbulence. Simply angling the inlet ports could give a vortex inlet pattern increasing the mix. The exhaust ports seem to be the same size as the inlet ports .... yet the gas pressure they will operate at will be higher (at least at first opening)! As the revs increase in your engine you will reach a point where the inlet and exhaust balance giving a knife edge power band (or alternatively a knife edge fuel efficiency curve) You will have a gas flow within the block that will go one way and then reflect to the opposite direction. Exhaust into the inlet and then back out as pressure reverses. This may be reduced by having the correct size of chamber between the engine and the blower. Dependent on the relative sizes you may get a "boost" from the crankcase pressure building up on the down stroke and adding thrust to the up stroke, effectively smoothing the output power. This may give a sizable benefit if tuned well! OK, enough prattling from me ;o)

I think this might work if you get proper timing to that rotary valve but, that fresh mixture in exhaust might give you some troubles.... I think if you make long exhaust pipe it will give you some back pressure and without pipe you will have flamethrower..... but these are just my guesses....

Love it when you get all passionate about 2 stroke design... makes me want to....uhhhhh watch it again, yea that's it.

if you are firing fuel air mix out the exhaust you could probably put a cat to light off that extra fuel and air then use the gas to spool up a small turbo to help reduce the load on the AMR300.

I feel your electrical pains! My house was built in 1910. It later had knob and tube wiring ran. Some of the knob and tube wiring is still in use. We are slowly replacing it. Good luck. You might get with the turbo snowmachine guys here in the USA and see how they do it. Some of those sleds make crazy power.

With the power stroke being in the top half of the stroke maybe off setting the crank and cylinder bore centre lines to reduce rod angle at peak cylinder pressure would help? It can also change the duration in degrees of the other timing intervals which may be a benefit?

Interesting idea for sure. Makes me think about detroit 2 stroke ship's diesels. Anyway, adding a high pressure injector could avoid all waisted fuel. But I understand injectors in a two-stroke will potentially limit top end rpm as they struggle to follow on mechanically.

if this works there are going to be a lot of people proud of you !

Terribly inefficient but should make alot of power. I think the exhaust port needs to open slightly before intake ports to prevent damage to reeds.

Great design! What about also running a rotary valve on the intake with the blower feeding into a pressure chamber. This would allow the blower to not deadhead and do productive work when not feeding the cylinder, allowing a smaller blower and reducing losses. More Horsepower! I'm going opposed pistons.

Hi ... Brilliant video ... I think you won’t need a Reed valve as whilst the ports are shut the blower will still be making a head of pressure ready for when the ports open again .. a cleaner inlet tract will equal even more power .... I would drive the blower with an electric motor to remove the parasitic loss so even more power Andy

Seriously cool thinking! Amr blowers should be able to handle the rpms well and you can remote mount and intercool it with ease.

I feel like I am looking into an ikea showroom when he makes video in his house. LOL.

Need to flow coolant around the charge to cool the compression . would be nice to vary exhaust disc timing, maybe two so that it is both close and open timing can be varied

Awesome design. How about fuel injector(s) in the transfer layer aiming directly into the cylinder? Maybe to also combat any slight lull in the fuel mixture flow? Would that break laminar flow along the full intake surface area... or something. Hope I'm in the right city if not the right ballpark with that. Thought for later if it doesn't want to run right eh. Have a good one!

I know that you have what it takes to make this work and I for one will be cheering you on once you have made this a success. Awesome work as usual sir 👌🏻

Nice idea but you will maybe experiment leaks on the rotary valve and this will change all the ports calulation. Also, how will you lubricate the crankshaft and the piston bearing ?

Great concept! I think the key for max rpm and with that the max power will be the timing of the exhaust valve. I‘m sure there will be a kind of pressure wave/ resonance effect within the exhaust port, that has to match with the closing of the cylinder ports at the „right“ rotational speed. Peak in the torque curve will show, where in the speed band that effect is most effective. Can‘t wait to see this run on your dyno including the way to find the right setup. Another thought came pretty direct in my mind: compressed air is hot, so a direct injection for the fuel could improve the end temperature of the compression before ignition and with that increase the power output. The injection could also be done into the transfers to get such an effect.

Put a secondary spark plug in the exhaust on the same cycle as the cylinder. Then you'll have a working pulse-jet stage!! Maybe you can use it to add some extra thrust, or even make the back-pressure if you advance the timing on the exhaust pulse jet stage ;) No valve needed!!

I might have something to add to that design. Instead of the rotary valve at the end of the exhaust duct you could use blades (picture a guillotine) that will close all the exhaust ports. So blades sliding up and down in the sleeve in their own grooves. I think that way you will have more mixture in the cylinder since the volume of fresh charge that would be used to fill the exhaust ducts would be forced to fill the cylinder and you could start building the pressure in the cylinder whenever you want. I think those blades could be moved either mechanically or with electronic actuation (like solenoid valves or something. Awesome idea keep up the great work!

Gave me Screaming Jimmy vibes. Then I looked at the comments and noticed I wasn't alone :) Awesome bunch 2SS has gathered :)

I think you've gone mad - but I won't stop watching!

How about heat? Exhaust gas are going in the ports and that will make it really hot. Idk I just guess but it seems really nice and it has potential.

I'm pretty sure you'd pick up power and efficiency by having more rational timing. Keep the brute force wasted raw fuel thing going but not straight up running the same timing on both ports.

If you're looking at supercharging then basically directly scaling up a 3.5cc nitro rc engine with the supercharger force feeding it would be a fairly simple option. No valves of any sort anywhere and barely any moving parts.

An engine's usable power is the net power after powering itself. Driving a blower, water pump, alternator and internal friction are power deficits. Engine design must include all aspects of a running engine. This is one of a thousand ideas that will allways be just an idea because of the universal law of entropy.

Sounds like this thing will be a fire-breathing monster.

intriguing. I think it has all kinds of potential. The first 2 big things that jump out at me, #1. the challenge of setting up and timing the rotary valve. I suppose if it's geared/chained to the crankshaft with proper even/consistent timing and reliable at high speeds, then it could be feasible #2 the reed valves on the intake resisting pressures and the supercharger constantly making pressure.. might require a big enough chamber on the intake side between blower and reed valves to give it a cushion like an air capacitor, OR a blowoff/bypass valve to vent excess supercharger pressure when it's not being asked for. Totally rad, quad ducts remind me of a Mario Kart 64 battle

I can understand where Alex is coming from but surely the engine has to power the blower so it can become the world's most powerful 50cc 2 stroke engine, and that will take a lot of power. One thing that concerns me is heat distortion and lubrication of the rotary exhaust valve, possibly needs to be ceramic which is heavy. I miss the dyno testing of the SPX running normal pump fuel. While very interesting sadly I feel Alex is getting a little lost along the way as the initial idea was to beat the Dutch 50cc tuners.

Have you considered a opposed piston design? This will have uniflow scavenging, inlet and exhaust ports operated by the opposed pistons, high thermal efficiency ( no cylinder head) and unlimited scope for radical port timings. Even Formula 1 are considering this for 2025!

It’s going to be a fire breathing dragon, quickly build it, bring it on.

Interesting, I'm really curious to see how this short circuits with the ports cut the way they are. Could be turbulent, but seems that you could use colored water to test a mockup. Also wondering if the exaust valve would be needed, long term, if you adjust/fine tune the port times🤔 keep up the great work.

Years ago, I remember a 2 stroke kart racing engine that had poppet exhaust valves in the cylinder head (4 valves).. and 360 degree surrounding cylinder wall intake ports .. that would be perfect for Super charging.

Is this not a twist on the Detroit Diesel ? Love your ingenuity and determination.

With a 50cc cylinder displacement I think the effective capacity will actually be somewhat larger. As soon as the transfer ports are uncovered on the power stroke, the mixture within the inlet/transfer ports will be ignited and increasing cylinder pressure and giving the reed valve some serious punishment. Might want to check rules for Bonneville etc. as would hate to see you get it working and be disqualified. This assumes you are using port injection (or carb), which you seem to imply. With direct injection this wouldn't happen, but then the exhaust gasses expanding into the transfer ports will decrease cylinder pressure. Rotary valve sealing could be a whole research project by itself!

if you fail 1000 times, that just 1000 times closer to getting it right. keep up the good work!

Same like a 2T diesel. Rotory valve in exhaust not be good. Better use valve in cylinder head.

Awesome work And your house looks really beautiful

So problem that made itself apparent to me is you need a way to keep the bearings lubricated and the needle bearing and crank shaft bearings are open to be lubricated by the fuel and with your set up I don’t see how you will lubricate them. If you increase the pressure two strokes are known for being unstable, if you do such thing then you risk blowing the motor and sending pieces of your piston out the exhaust. Make sure the materials are decent or you will blow every one you make.

seems like a bomb with all the mixture but hey, that is just me LOL

Could you adjust/time the mixture input by moving the reed valve up the pipe for fuel efficiency haha.

Hello, you have realised the burning charge will ignite the air fuel mix in the 4 ports as soon as the piston opens the ports, causing problems, so why not go one stage further and link all the ports to a single inlet - exhaust chamber around the cylinder. By opening the exhaust port to the exhaust pipe a long straight small bore pipe will still have gasses moving away from the engine causing a vaccum that will pull the burnt gasses into the exhaust with any ignited mix as well. A rotary ported compressed inlet will then open at bdc or just befor bdc, letting the Compressed mix to enter by all the ports until the piston closes the ports and the rotary inlet valve can be closed. This would allow further scavaging through the exhaust befor closing the exhaust rotary valve. This vaccum would help the next cycle by aiding to remove the spent gasses when the piston ports open. The exhaust rotary valve would need to be a drum not a disc so a profile (slant) would allow exhaust port timing and duration to be changed. Tricky to get the ideal gas flows and timing optomised so easily changeable drums would help the search for the optimization of port timing..

Love the new concept, also would love to see PIP with a slender bridge pushing some BHP! I want your cylinder to blow the big names out of the game 👍

i'm in no way knowledgeable enough to give any advice, however I think you need to get the rotary valve and the reed valve as close as possible to the combustion chamber. Exhaust gases will have a hard time getting to the reed valve and keeping it close while simultaneously exiting from the exhaust. I think you risk a little bit of burnt gases remaining in the combustion chamber compressed together with fresh mixture.

A bit of blowdown would perhaps help I think, only like 10° just to get some pressure out of the cylinder and stop flow reversal.

The reed valve in the intake could blow out in a hurry. You might consider a disk valve there too.

Love the concept combined with fuel injection the airflow should keep the engine cool

how much pressure can the reed valves actually take? maybe a rotary valve at the intake side as well? mad idea and i love it! cheers!

The exhaust gonna be glow. I think to increase efficiency switch to direct injection of fuel.

I wonder if there is enough of the fresh fuel/air mixture coming out exhaust to feed a small ram jet engine. Or just put some kind of igniter in exhaust for some flames and maybe some thrust. Just thinking of ways to take advantage of the leftover unburned mixture.

💥 YS 115 engines for rc airplanes use a rotary valve off the crank. 2 stroke / 4 stroke hybrid.

Good luck mate!

The amr300 has really been a revelation for cheap and readily available supercharger tinkering. It does seem that the easiest and cheapest way to make big power is forced induction. Port angle, manifold flow, exhaust resonance?? Who cares, just cram it in there with a blower. I'm not sure if the supercharger to cylinder manifold design will matter with such small displacement but maybe need to consider capacity to hold full pressure charge between intake cycle if going to really high revs?

I really want to see this cylinder working

Since you will be burning a lot of fuel outside of the cylinder, why not make this a pulsejet hybrid and feed that hot fast exhaust jet into a turbo to make use of all that energy to drive the compressor! It then becomes some kind of crazy turbo jet two stroke hybrid.

Cylinder with only exhaust ports and have oxygen and fuelinjection. Pure oxygen contain three time more o2 then air = you can use three times more fuel = three time more power.

Direct injection could solve the fuel inefficiency problem since it could inject the fuel after the piston has passed the ports and then the blower can blow out remaining exhaust gasses without blowing fuel out the exhaust. Although i don't know if it is possible

With that kind of fuel which is not burned going thru your engine, your should problably try an afterburner too... ! Secondary ignition which again can fuel an jet engine...!

I love this series and your engineering skills! Very interesting! However I have a question. So, 2 stroke has the reed valves that control intake air flow(basically lol). So when the charger is forcing air in, how do you expect these reeds to work?

let me preface this with the fact that there should be a better preface here😅If you worm drive the blower, might that prevent back spinning it with the combustion pressure? Essentially, making it a valve. Could direct injection alleviate some efficiency concerns while still providing necessary air/fuel ratio?

Theoretically everything you explain is correct, but practically other factors come into play. 1. energy required to rotate the blower and the rotating valve. The theory claims the high hp, but the hp that the extra rotating parts will use, if you subtract that energy, you won't be left with much profit. I would advise you to continue with your previous project. Put the bridge how you like it and test it out. What you do now is that you create a 2 stoke puzzle for yourself, which will take a lot of energy to puzzle out in time. your previous project is a new 2 stoke base that can break a record .. ps keep up the good work

YOU ALWAYS SAY MORE POWER, BUT IN WHAT BAND? I FEEL LIKE YOU'RE CREATING A GRENADE LOL

I'm hearing he wrecked that cylinder with the second start up

You’re an absolute madman and I love it

Here you will get detonation in the exhaust which will be able to give back pressure, as the exhaust ports and intake ports are equally high, the filling line will be poor due to back pressure when the cylinder is to be filled??

100% of bore, on the back burner, or on the shelf, so to speak. Rock on.

Hi, i know nothing about 2stroke, but do the piston rings like this all sharp trasfer from open to closed att the same time, could you not use more organic design on inlets and outlets when yup have i blower. Sorry for this stupid questions. But i very much love your commitment and wounderful "slugger" spirit. You rock!

Man! Your mind is in fire 💪🏻💪🏻👌. Love this idea. No efficiency but we don’t care

This is amazing! Love what you are doing! 🙌🙌❤️🇦🇺

You should consider direct injection and time the event after the ports are closed.

Is there any chance of the combustion igniting the incoming charge since all the ports have the same "timing"? How about an option with a single intake valve in the head that opens right about the same time as the exhaust port is covered as the piston is on the compression stroke? Then again, your design could be the perfect solution haha! Awesome content regardless!!!

Now it's getting interesting! You may finally break my 27 crank horse power record! Dang...

That used to work just fine. It's a microscopic version of the EMD 567D3. Please build it, I simply MUST hear the sound of it.

what will happen to the trapped unburnt mixture in the exhaust ports when the combustion makes contact with it? huge exhaust flames at all times ? very interesting concept tho

Ambitious for sure.

In this design you can Use normal 4T oil for the crank, rod etc. nope?

Brilliant 👍really enjoying all this new content lots to learn, good job

That blower is going to take some power to drive. Question is will the engine produce so much more power than it otherwise would have to make it worth the extra parasitic losses from driving the blower. Also it'll be cranking out unburnt fuel through the exhaust like 45 bastards so that header is gonna get REAL hot! :) Can't wait to see the result.

Your filling the exhaust ports with fresh air and fuel and in the chamber behind the rotary valve? Surely this will ignite too?

What is the point of a reed valve when there will be always a pozitive pressure keeping the reed valves open?

Keen to see it ..build it

Why not transfers for entrance and valves on the head for exaust?

And when you start concerning about environment and fuel costs, you build some direct injection system? This is really a great design.

Wow sounds cool, but.... what about overpressure on the intake when everything is closed and the huge parasitic drag spinning that HUGE supercharger. BTW if you want that supercharger to last take it fully apart and clean all the crap they leave behind and put it a good set of bearings. If it should backfire with a draw through system you have to have a way to vent the explosion of the compressed A/F mixture unless your going with direct injection. Personally I think crossflow would scavenge better. If you can work out all the issues it will sound really cool. Hey instead of resonance of your current engine put the supercharger to work as the secondary induction system that comes in around 6000 rpm, just use a centrifugal clutch. I still think using no ring on the current engine is the way to go. Just lap the piston to the bore at operating temps so it fits perfectly. The only problem is you have warm the engine fully before it will move, just like a Formula 1 engine. The piston could be made much, much lighter so you can turn even more RPM's! Best of luck!