Alex, I'm sure I speak for everyone when I say every video of yours is definately a win!

^Woooow an Hour Video how nice is that, i gonna make me some popcorn now and enjoy the vid

Almost an hour of madness, this week just getting better and better. Keep up the good work sir! I love it❤

The fact that all this is just to test the cylinder design And if it didn't work there is a big chance alex will try a whole new design until he will reach his goal Just shows the dedication this man have ❤

When I was playing with my Ehrlich boost port engine I was surprised at how sensitive it was to port height. I could not get it running at all until I lifted the barrel. Fussy things 2 strokes.

We called those "wrist pin buttons". We used them in naturally aspirated and blown applications. They were made of Teflon, I believe.. We did have recessed buttons, 0.35mm per side. Room for lateral heat expansion of the wrist pin.

Onnittelut lienee paikallaan. En ymmärrä miten kenelläkään voi olla noin hyvät hermot, että jaksaa jatkaa vaikka menee viikkoja että mikään ei auta. Onnittelut ja paljon kiitoksia aivan loistavasta kanavasta. Innolla aina odotan👍

In the '60s, we ALWAYS used polyurethane buttons in the wristpin cavities, outside of the circlips, to prevent the deadly "double-tap" of a loose wristpin hammering it's way through the cylinder wall. Oftentimes, some eager beaver would widen a port too far and one or two rings would bow out of round, letting the charge leak past at the chord where it hugged the piston. One fella put in a third ring on the skirt, more to compensate for the very rich oil/gas ratio he used than anything else, and received much better burn rates, as the still pressurized fuel could not escape up the side of the piston and out the exhaust port. Just some food for thought, as if you would need any more. Never forget that we are all rooting for your success and if it takes forever, we'll still be there.

Those 49 minutes just flew by in a moment. Well done 👍 😊

can't argue with a 50% improvement, even if it's short of where it should be. Well done! I enjoyed the longer video. Now go celebrate a win!

Underbart med långfilm! Loving the content🔥

my favorite mad scinetist does not dissapoint, the "wood router adventure" seamed bit sketchy ngl but cudos for the idea, i would not think of it :D it looks like it will make some power

last time i saw this engine, it was bolted to a bicycle and was just mainly ideas. So awwesome to see this kind of progress nad hear her scream like a banshee!

Be careful about assuming the Exhaust temp is low due to the probe being close to the piston. Remember there is overscavenged mixture being pushed back into the cylinder that is sitting in the duct , thus the probe will read low due to this - not high. Also yes you are correct , if there is linking between the Exhaust ducts and the case at TDC it will run like shit with no power , same effect as having the piston skirt too short and the case being exposed at TDC . We are running quite alot of port linking overlap thru the pin bore in current race engines , yes the pin caps do help power , but its not a huge issue like the TDC one. - Cheers Wobbly.

Really pleased to see Alex has got through the doldrums (a nautical thing!) and is well motivated again. I’m so inspired by this I’ve upped my Patreon payment according to the BHP increase (around 50% 😁). Great work Alex, but don’t get too obsessed 🧘

I think that the flange welded onto the belly of the pipe creates a harmful volume that strongly disturbs resonance... I suggest restoring the pipe as it was originally, in order to exclude a further negative factor. Keep working man, I feel you're in the right way 💪

"It's the next day and i've changed my mind" Man! Change one thing at a time!

I'm running a 96% of bore bridged exhaust in a 265cc ATV engine. Specifically an '88-'92 Suzuki LT250r. 69.5mm/70mm B/S 125.5mm rod. Lots of welding and reprofiling of the ducts and entry angles. It makes good power and torque with a good pipe.

Absolutely amazing. Great video. And so much fun watching. You had fun as well. It was all just awesome.

As usual brilliant content, fascinating to see you working through all the possibilities.Cannot wait for the next update !!!

11:45 "Just gotta figure out what's going on" ,...mate never have truer words been spoken

Another incredible video, and with the added bonus of being feature length……your levels of patience and perseverance are something to be admired along with your knowledge of 2 stroke design and function.

Well done keep it up

In the 80's I remember using balsa wood glued with epoxy to fill the piston pin was a common practice in 2 stroke racing engines.

That was a nice episode! I had almost lost hope with your rotary valve. It was really funny seeing how the piston pin plug didn't make a difference either despite strong assumptions and even simulation 😁 Also the transfer hooks seem to do nothing either. I was planning to try adding the hooks but now I lost hope for that theory too. I think it has to be the exhaust. Wobblys theories have led us to make the exhaust duct too small. It is compounded by the length of the duct following from the duct cooling idea. Measure the duct outlet area, I say it has to be 25mm circular at a bare minimum and no restrictions in the middle. The pipe header is probably better to be at least 28mm. Think about the 80-90cc cylinder kits that are pushing 20hp+, they all have about 30mm exhaust flanges and the mass of the outflow is not going to be any different in a 50cc cylinder if you are going to push the same amount of power.

I have found for getting to far hard to reach locations that if you get sticky back 5" DA disc sand papers and make your own much longer spiral spun porting sand paper cartriges that is mostly spun outward around of itself works pretty decently still slower than a carbide burr for sure but probably more controlable and quicker than a file work! The router idea looked like it was certainly pushing of ones controlability limits for sure! Im glad to see that you didnt end up having to file13 of the entire cyclinder! As always I very much enjoy following your progress and am very glad that you take of your time to share of it as you do! Cheers and thank you!

So excited for this one! What could possibly go wrong?

15:31 i love that you explain the thoughs. More videos im exited Amazing video!

When you were brainstorming you mentioned every conceivable potential power robbing problem known to man, but it seems to me that most of them would be the kind of things you would consider when you were trying to tweak the last half horsepower out of an engine. One thing I didn't hear you mention is the possibility that your dyno readings might be faulty. Compared with previous runs, the engine now sounds so robust and frisky, so to speak. It starts, idles, and revs to high rpm rather nicely now like a healthy engine should. It's hard to believe you're not making more than 9 hp. Could it be the dyno data?

Hell yeah, any progress is good progress! Go to see a really positive outcome in this video!

Plugs on either side of the gudgeon pin are used in many aviation engines.

Honestly. Keep the longer videos coming. Watching you trial and error, and error and trial is great. I know it’s a lot of editing, and 10x as much physical work just doing the work to make the videos. But we will watch them. This video is a close second to your Frits germany tour video. Great work. A win indeed my friend.

Just remembered from college the double diameter piston 2stroke, large piston skirt with a step reducing the piston crown. Useless because of long term friction, weight and cost, but maybe for the world's most powerful 2stroke ? Maybe.this would make your large crank volume work. I think your pip engine is more rewarding long term. Good luck.

What an awesome episode👏 I’ve been following this crazy channel for a bunch of years now and I’m still glued to every up and down, and up and down… and up… Love it!

50min? Långfilm förfan! 😎😎👍👍

Congratulations Alex 👍🏻 easy is worth nothing and good results come after hard work and persisting through all those hard times your getting there. I would say 9 HP from a naturally aspirated 50cc engine is a good output. Love the channel Alex 👍🏻

Many people say that adding a thin coating of grease to both sides of the new lower cylinder gasket will make it not stick, and thus reusable in future disassembly

Feel like this was your true first video back from time off ❤ great content brother

jazz and 2-stroke madness. what a marvelous combo

Dear Alex, I can't imagine that your engine does an almost insane 19,000 revolutions and only produces 5.5 hp at 15,000. I assume there's something wrong with the dyno.

Thanks for this update! What a good way to start the weekend 👍

Congratulations on your WIN mate! On the upswing now. Thanks for keeping me amused last few years.

Blimey! I was glued to Alex's video. Except a small pause to take a piss and catch my breath. Love thus stuff, thanks Alex.

“I think I’m on to something, I always think I’m on to something” - Two Stroke Stuffing

Keep on fighting the 2 stroke gremlins.

Excellent! You're extremely patient. Keep up the good work 👍😁

What a great video, great progress made. Could I re suggest plugging the B ports with oiled toilet paper to stop them working which will help give a definitive answer to their performance. The wrist pin could have being blocked in the same way. You are now obtaining enough revs to be able to get a good plug reading. Are you testing the engine from cold. Over a year ago I sent you a email about a video Mark Atkinson did on his land speed bike which had poor performance. The conclusion was the transfers were too large giving good flow but low velocity. I am still a firm believer in high primary compression. It was one of the major tuning area's of the 70/80's it worked! Lowering the exhaust port is a major step in the right direction, you know my feelings on that subject. As you said if the spent exhaust gas is not cleared totally it is re burning the left over spent gas which doesn't help perfofmance. Finally may I repeat the old saying " you have to get it out quicker than you put it in " It's nice to see you back in action! PS. Having watched the video again I can see the water temperature guage is working. I wish the temp guage would not jump about by upto 9C so rapidly.

now maybe experiment with more crankcase compression ratio to help the intake charge enter the cylinder at a higher velocity so it won't get sucked out the exhaust auxiliaries.

Congratulations, i appreciate that you're willing to reevaluate the original calculations and concept to determine if the engine is going truly deliver on your promise. Can you put a cylinder off a known 50cc and see if the crank case is delivering as intended?

Great job Alex I’m sure you will crack it , glad didn’t play the music all though the video.

To reduce inner friction: Consider ceramic coating. CERIDUST 9205 F is highly recommended for this task. Clariant is the manufacturer. The results are significant. Personally using it for four-stroke Diesel and Gas-Engines and for Two-Stroke Diesel (Detroit-Diesel V6 Marine) and for Two-Stroke Motorcycles (50cc>750cc) with separate Oil-tanks. Works properly for +10years of experience.

Hej Alex! Just a thought. Har du testat bänken med en motor du vet effekten på? Alltså är du helt säker på att siffrorna du får ut är korrekta? Ta ”vilken motor som helst”, koppla den via växellådan i samma ram och se vilka resultat du får. Eller ta hela högen till nån annan med testbänk…

Awesome video Alex! I wonder have you had a known power bike on that dyno recently to baseline it? Your engine seemed to be running very sweet. I can't understand how it could run so well but not make any power, but I'm not any kind of 2t expert

Idk about the rest of scandinavia, but its J dag in Denmark. So happy J dag and drink responsibly.

It's like the inertia of the gasses is becoming an issue at these RPMs, like there's not enough time to start moving in the first place. It might be a good idea to start measuring intake mass air flow to rule out any obvious restrictions or your intake mix being shot out the exhaust. Edit: it could also be that port timing becomes an increasingly big issue with the unconventional exhaust duct design, it will take much longer for the pipe pulse to arrive at the edges of the exhaust port than the middle, this would make the port inherently bad at producing peak power (though excellent at making wide band torque).

For somebody that has watched almost all your videos can you please please try loctite 518 flange sealant when you reassemble your two-stroke please.

Your explanation@ 37 min about exhaust velocity sounds like it's designed perfectly for boost application. Boost pressure would keep the exhaust from contaminating the crankcase.

Yes! Success!! And it runs so cleanly.

Progress!!! Alex keep going. I’m finishing a 3 year rd 400 build right in time for winter!!😂😂😂😂😂

Im so happy thr music is back that i git my headphones for this video

To seal the pin find some aluminum freeze plugs in Europe I think you call them frost plugs And install them with some Red lock tight will retain an seal them then if possible cut a circlip groove in ID of the pin to make sure the can't come out. Maby shave the pin Length down very slightly so you could put a very thin steel shim Is behind The existing risk pin circlip Then don't use lock type maybe that'll be a bad idea if it melted That would make sure the frost plug Could not come out and do damage Something like that I don't know. Of the watch your videos because they definitely engage my mind. I admire your perseverance. That's from someone that has made a living working on automobiles motorcycles and internal combustion Engines for 26 years More than half my life keep up the good work buddy

Not sure what the changes are, but the latest ignitech firmware is 1.09 and you are still on 1.06. Might be worth updating in case there are any little bugs with the curve extrapolation or something like mentioned.

I loved your channel like 5 years ago, and still love 😅 well done 😌

Fantastic as always Alex! Keep at it, I’m confident you will get there!

Wrist pin buttons are common. Just go that route vrs them 2 piece pistons with buttons you don’t need wrist pin C-clips

Good to see you smiling at the end.

Very nice, congrants on that win i was anxious to see you with that long and deserved victory!!!!! Looking forward to ones that will follow!! You win every time you don't quit!!!

Did you ever think about tacking the Aprilia rsa 125 exhaust pipe (tubo 102) and scale dowm to a 50 cc ? Maybe it would be a bit longer for your engine rpm target, but if the ratio (engine cc/exhaust volume) is the same of tubo 102 ad also the angles, you will probably see some better results

I will not believe that its just 6,34 HP at this sound and 19.000 U/min.

Very nice to have the music back during the building segments! :) Makes it so much more watchable.

its sounds smooooth. good job.

Dang Alex, you are on a roll again. REALLY good stuff.

i barely understand everything about ports and timing and such, but your videos help me learn. im always happy to see you uploaded another video, especially after a long day of working on my bike

Really enjoyed this week's edition!

Ignition timing can make big gains or losses, but also you could be losing power through parasitic load through the engine case you're driving through

We used to fill the wristpin with simple cork. Worked perfect and super light weight

Keep going. There is an old South African saying "When at first you don't succeed, you just have to suck harder"

I can´t wait for the next video and I enjoy it so much every week a new video comes out. All the thinking, the trying and problem solving it just makes me smile. This week definitely a win after so many weeks but all weeks you are winning anyway. It is not a learning curve, but a winning curve 😊

You must have the patience of Job! I admire you.

Congratulations for the steps in the right direction. I really enjoy your journey with this little SOB.

brilliantly entertaining video, thank you, Alex.

YES! A long awaited progress and a happy ending to the video has finally arrived! Love it! ❤ Fast forward to next Friday please 😁

It might be a good idea to invest in a cheap FLIR camera so that if there are bearing or friction issues when you try other configurations they can be easily and quickly identified so they dont mess with results

I know i keep commenting, but i have an idea, what about casting air cooled test cylinder, with transfers that are capped externally with a sheetmetal and epoxy cover, to design the ports you know will work, then take a mold of them, and make a jewlers wax casting of the ports, and attach them to a 3D printed cylinder. Then cast that cylinder! It will be 99.8% perfect, just require sligt porting to smoothen up the ports!

Love the longer video and great to see some progress keep it up 😎👍

Alex your a very smart bloke and I'm sure you'll have it singing and pumping out the horses in no time

Thank you Sir!

I really like your videos. Please go on with your journey!

love it, fair play. you are working through problems. Huge hurdle passed with the seal heating issue.

I want you to succeed so badly, and you will. Stay Strong and Stay you.

Maybe you get a wrong egt reading, becose you are so close from the piston itself, that the probe actualy end up reading some mixture during the "extra" mixture pushed by exhaust until the wave kik that inside again... i think you get it.

yes

a big win yes. watching your content is aways a win just for the record

The most tenacious man on KZfaq.

I LOVE the new music! What a lovely smooth and calm jazz! ❤

Woo now its time to start adding one change you dreamt about at a time making that work the best it can and adding another invisioned change. I cant wait to keep following along with your project.

Sjukt mycket igenkänning på allt du gör! Uppskattar att du får med tankevurpor och småmissar. Varje video är en ”win”. Kämpa på 🎉

Recently I been thinking about reciprocating file setups. Don’t know of any. Like a file that fits a jigsaw or mini/full size reciprocating saw ( commonly referred to as a saws-all in the US ).

my bday was yesterday low-key was looking forward to your video more thanks for finally putting up the next in the sega

Recirulating exhaust gases into the combustion chamber will lower your exhaust temps. That’s how modern diesel and petrol engines meet high test standards.