Homemade DOUBLE GX200cc ENGINES !? 400cc 20hp

[@benjamincresswell3713]

When I was 14 a younger friend asked me to show him how to rebuild a small engine. So we got 2 Briggs and Stratton 3hp engines and pulled them apart. He did one, and I did the other. We did not bore them, just new piston rings, gaskets, spark plugs and cleaned everything up real nice. When done they both ran. Then I had 2 little 3hp engines that I didn't know what to do with. I had a Go-Kart, but it had a 5hp Briggs on it, so 1 puny 3hp did not interest me. Then I thought about combining them. I pulled the cranks back out and took them to school and in machine shop I threaded the outside of the pilot shaft for the recoil on one and inside the pto end on the other so the two crankshafts screwed together. I made up a common manifold and braised them together with something like Fonson or Phonson. ( I can't remember what it was, but it was not braising rod) When I got all done it worked and I really enjoyed the sound of a 2 cylinder engine on my Go-Kart. But, I got a lot of criticism for not timing the pistons. I had simply screwed the two engines together and wherever they were when it got tight was it. Some said the timing should have been so close that one coil could fire both for the most hp. Some said the two fought each other and it made far less than one by itself. Well, I had ridden my Go-Kart with a 5hp Briggs on it plenty, so I knew how much power that had, and I could dispel their criticism because my 2 engine Go-Kart had a lot more power than that single 5hp did. What do they say about proof is in the pudding? I had a lot of pudding time with my 5hp and this double engine had a lot more pudding. Also Too, I wonder: Did the engine in this video sound like an old John Deere B engine? I had a 2 cylinder engine on a two wheel walk behind tractor called a Standard Twin. BOTH PISTONS WENT UP AND DOWN AT THE SAME TIME TOGETHER. They fired alternately. It sounded perfect. I have had engineers tell me it couldn't have or it would vibrate itself apart. Well, somebody forgot to tell The Standard Engine Company of Minneapolis Minn. or just never bothered. Because they made a lot of them from the1930's to the 1950's and they didn't vibrate at all when running. John Deere I have read thought it would be too hard to balance their 2 cylinder engine if they had both pistons going up and down together at the same time firing alternately, so they did like the guy in this video. With the John Deere one piston fired at TDC while the other piston was at BDC so there were two power pulses 90°apart, then a long lag of 630°? ( something like that, do the math I may not have it right) until the first one hit again. What we hear at idle speed is the 1st one, it has to bring the engine speed back up from the long lag and pumping losses, and that makes the 2nd one inferior in sound, which is where they got the name "Johnny Popper.' Until the engine worked hard enough to have both power pulses working hard, to me, the John Deere B always sounded like it was misfiring. Hey, that was a long time ago and I'm gettin a headache from trying to remember it. ben/ michigan

[@DDC59805]

Odlicna stvar, eeee sad na to staviti turbinu :D

[@mazdamaniac4643]

Spark plugs with multiple electrodes doesn't make more spark, it forces the ignition coil to work harder than it should because it's trying to drive two spark 'plugs' from one coil output. You end up with either multiple weak sparks per plug, or the spark becomes unstable and ignores one electrode completely at random. Just use single plugs for a strong consistent spark. You may also want to think about timing the crankshafts so they work together, therefore each engine fires 360-degrees apart. It'll smooth out the fueling through the carburettor. That'll result in more consistent firing, less vibration from a more balanced power delivery, smoother overall torque...all of which is ultimately more reliable and lasting fun.

[@christiantrab6160]

Great job! On two 4 stroke engines, you could have timed the pistons, so they are both in tdc at the same time, and one fires and the other is in between exhaust and intake stroke, then the next time they are in tdc, the other will fire and opposite. Right now it is an oddfire engine, where you have uneven gaps between the fires - but I like it! :-)

[@platyperrin]

Would that vibrate more than having them balance each other? Genuine question, i really dont know

[@christiantrab6160]

@@platyperrin Good question, I don´t know really. But I have been tinkering with motorcycles many years, I know that a lot of the 2 cylinders are twin as they are called, where the pistons move side by side, so that the combustion strokes are one hole rotation from each other to make them run smooth. Anyway, it works :-)

[@W3c16B]

I would try two carburetters instead and you need to adjust them 100% precisely. I don't know where to get it, but many many years ago I tried to adjust doubble caburators using a vaccum measuring system, on Audi 80, on the fly on a highway, we meassured the vaccum at 120km/h because they didnt work even at that speed.. In short terms we drove 120Kmh, notiched the vaccum differiencies and stopped at nexe haigway exit, adjusted, drove again.. VERY interresting how a very small difference, could give a huge result in engine performance. We adjusted the nozzels with very small round metal files. If the engines are not running at 100% precise torch, one engine will have to use power to turn the other. It's difficult to explain, but if you think about it it actually logical, IF you use a single caburetter, the distance to each cylinder must be 100% the same, polish the tubes on the inside as mush as you can, and the same goes for the exhaust system ( maybe two exhaust systems are better?) if not same lenght, one cylinder will sort of block the other cylinders outlet a little. Finally you could try to adjust the angle between them, eventually 45 degrees, and adjust the crank so it "kooks" like a Harley? just for fun :)... or buy a 400cc engine instead hahaha

[@orginyigam732]

How is it even possible.... Amazing.

[@MustafaAlemdaroglu-no5vi]

If only a turbo was added to this

[@FrustratedBaboon]

People stop comments of criticism of his work. He busted a theory every one of us had as a child growing up. I used to think if I could connect four of these I could make a car etc.. He just made a video to show it.

[@hankcuccina5260]

Don't forget his brilliant editing.

[@honeybadgeractual5734]

You should convert this to a draw through HCCI style engine, and use water injection just before the intake port where each case pulses it's own or each other's fuel pulse pumps, you may want to make sure the pumps will handle methanol or ethanol. Now you could use a butterfly as a throttle, and set it up to inject a small ethanol (vodka, 40% ethanol) boost each cycle. Homogenous charge carburetor runs better for a twin cyl than your carb, and the ethanol aka vodka injection system helps keep the engine clean, keep from overheating, and allows it to run very lean with less risk of issues, which is the main issue with HCCI carburetion. Could boost your low end torque and horse power higher, certainly will boost fuel economy.

[@МилошБрат]

Svaka cast! Mislim da je mogao jedan prekidac da gasi oba motora, samo ih povezi zajedno.

[@MetalStrength-]

Now we're talking, perfect job man, keep going ❤

[@liudon676]

The ignition switches can be integrated as single one by changing the wirings. Great job!

[@Rufusbully]

Masterclass! Very good bro!!! Greetings from Italy🇮🇹

[@support2587]

Finally a way to max out my Harbor Freight wood chipper! Seriously, nice work.

[@tkmad7470]

Fun project! An elastomeric shaft coupler might make life a little easier on the engines as it dampens the impulses a bit.

[@facereader99]

Wow! That is a lot of work. Thanks to your ingenuity and hard work!

[@lise1255]

Surprisingly great sound it makes 👍

[@foxwhiskey]

The whole building-process looks really very accurate. Congrats !😊 great job, nice vid.

[@jamsvaganza5622]

Begitu banyak yang dipertaruhkan saat dua mesin dijadikan satu, tapi anda berhasil melakukannya, luar biasa👍👍🔥🔥

[@philipjonathanmanoharan445]

Very good sir. For demonstration please clamp the engine base plate to the work table by using a C-clamp. You are a genius.❤

[@YSLee-xg8eh]

Your dexterity is amazing.

[@brenathedadal9929]

Thanks verymuch for mechanic engine study.. success always Mr...

[@IbisOffgridLiving]

Put it in a go kart now 😅

[@ewanbaxter9199]

Your videos are great, no language barrier and easy to follow with a sense of humour thrown in, makes for very enjoyable video

[@VanillaGorilla145]

Your level of craftsmanship is incredible you make me want to get out in the shed

[@geo2cv6tron14]

Really really cool, looking forward to seeing what such an engine will be used for 🤩👍

[@miguelpagansr6128]

Nicely done doctor, can't wait to see what it's going into. You're an evil genius 😂.

[@kikilafrite09]

Do a double carburetor setup with a turbo charger, that would be your best bet at making powa

[@vinniedurrant]

That's sounds lovely! Good job 👍

[@hankcuccina5260]

Very clever and very entertaining.

[@gordononkyo2713]

I was hoping to see a solution for two motors combined when needed and single when only halve power is required. This would increase efficiency very much. Maybe three motors could combined too in a usefull way part time clutched together.

[@Neoscae]

I am ver impressed , I honestly though it will not work since the length of the gasoline feed was to long, now I learn something new , thanks !!!

[@PPG_Kielce]

bro, I'm giving you a challenge: build a paramotor with this engine.

[@wuttichairc]

In my think, for 4 stroke engine must balance timing at TDC for each engine but one at Comparison stroke and other one at Exhaust stroke

[@disintegration83]

Exactly... Like a Fiat 500 / 126

[@coreysmith2774]

My idea has always been to make an engine mounting plate for however many engines you want (2, 4, 6). Instead of physically connecting the engines, they would each be connected by chain and a centrifugal clutch to a shaft mounted to the bottom side of the engine plate with pillow block bearings. The bottom shaft would act as a crankshaft in a sense, but you could run however many engines you wanted based on the centrifugal clutches.

[@ganprottas6259]

that is super cool! looking forward to seeing what it will power! perhaps an airplane?

[@victorriceroni8455]

That is sweet. Some of the best fab on youtube.

[@ABT14.MF-000]

Un travail extraordinaire Vous êtes génie doctor Excellente modification Me5👍👍👍

[@35gilton]

The engines runs very well together!!! What is the next level.. Create an V8 engine out of single engines??? 👍

[@JamesLuther-q6h]

Svaka cast ja bi mu stavio Hladnjak jer ima vise od 1 cilindra i sigurno ce se pregrijati

[@TheRCAProgram]

now put a turbo on it

[@TheRCAProgram]

@@OK75 Maximum power

[@damnyiffers]

Hope you've staggered the ignition strokes. One engine needs to be exhausting while one is fueling or your gonna have one engine taxing the other

[@andybes237]

You are such a clever young man.

[@rubberduck4966]

Having only one carburator you should use 360° as then the airflow is symetric to the two engines and therefore both engine-halves would produce the same ammount of power. At the moment you loose some power of the non-perfect airflow in the intake behind the carburator.

[@stevaughngammon1175]

I truly loved and appreciate the engineering and look to build on soon qnd can't wait to see wat beast u make with that monster unit..

[@Kieranzxt1]

Would be interesting to play with different crank phasing, 360 degree crank, 270 degree etc.

[@clayhunna7357]

brilliant, well done!!

[@sylkelster]

Now gang 4 engines together and add fuel injection. Fuel injection might be a tad easier to implement in that configuration. I hereby challenge you! I might try it one day myself. I have machine skills, but need to polish my fab skills. Well done sir.

[@surfkite1622]

We also manufactured general-purpose engines for 2-wheeled bikes and 4-wheeled vehicles, such as GX200cc ENGINES.

[@horstszibulski19]

Just get a "Y" spark cable and get rid of the other coil, the piston that is at bottom dead centre gets just a waste spark, but you minimize the hassle with two sets of spark contacts etc...great job, the decision against the governor and for a bigger carb will pay out... 😉👍👍

[@MissRepairmanLixa]

I really like the way you decorate your office, it's so beautiful, I wish you good health, God will always bless you

[@YTRYGamingTripZz]

Just going to put it out there but mounting 2 10hp motors together isn't going to push 20hp it'll probably be pushing 12-14hp at max, but Torq would be more of an advantage.

[@siyabulelankumane9760]

Only a technician can do that your work is a master piece a theory of an experienced engineer dream

[@_CRAZY_-lt1vn]

haha it sounds so nice

[@Polvoranca]

bravooo este señor es todo un profesional y madre mia que herramientas mas buenas tiene son el sueño de cualquier hombre qu ele guste estas cosas

[@jaszvjoroh2077]

It was brilliant.. bravo 👏

[@quietprolink5322]

Awesome entertainment. I am not fully equip neither tools or knowledge but have basic understanding. Very satisfying to watch. Great work on VDO editing and the hands on portion .

[@stevangubik6668]

Svaka cast👌😎

[@องอาจกันยาประสอทธิ์]

.

[@chrisosti]

I salute you! You, sir, are an absolute GENIUS!!! Now, you must follow the inventors rule...if one is good...two are better...if two are better...FOUR WILL KICK ASS!!! Get to it sir!

[@SteveTheCanadian]

This is amazing! Well done

[@TheOriginalAndysGarage]

I can see your welding skills are about as good as mine

[@gilbertoarturofigueroaarit6225]

You did an awesome job, you got a new subscriber here , I have to see the all videos from your channel

[@massimofusillo]

È fantastico vedere i tuoi video grande Doc👍💪💪💪

[@leomenchey3726]

That was very cool I liked the build I would have put electric starter on the one and then I will use a Honda Key dignition but wire the kill into both engines so you didn't have to do the stop button twice

[@quadrant2005]

i would be interested in seing this with the GX200 electric start conversion fitted to see if it would be able to turn over the two engines, nice work...

[@qubrochanel1755]

Top markotop masse.. buat aku aja kwk kwk

[@propelerMlbb]

bjir

[@HighTech.360]

mass production machine, Fascinating! video!

[@Roko3131]

...very nice, congrats bro!

[@stephen3727]

Great job for better than most people could ever think about doing

[@speedybuggy1677]

Very true work I give you five stars ⭐⭐⭐⭐⭐

[@Vanni_stelrooij]

Are you May be Alien??? 😂😂😂 Amazing work, great. 💪👍

[@DaveWLeech]

absolutely awesome job.. now i have a project to do myself,,instant subscibed also . appreciate the posting. and ill go through your channel and check out other projects also . thanx again

[@AidenRisk]

I have questions, is the secondary flywheel necessary? could you just modify the female coupler to fit the second engine and use only one flywheel with opposing magnets for spark? Maybe use one for a two cylinder? I’m thinking, if you time it so that the engines are on different strokes and the magnets opposite, you could get away with using just one flywheel, I think you could get some more high end power, a more responsive engine and save some weight by doing so

[@benskai2475akurfishing]

Very genius, senior. I like your brilliant idea

[@sindo7672]

one of the most bad ass inline twins ever! sounds crazy

[@SiempreConTrasto]

You may now play a bit with crankpins angle offset. And make a 270 deg offset just like in new motorcycles of Yamaha.

[@ari_setyo.86]

Getarannya seperti mesin harley😂👌🏻👍🏻

[@ncopp4358]

Where do you learn your machining skills? I would kill have equipment like that, but it's way out of my price range. And Im young/broke. Repect to the machinist out there.

[@onskuponsku_11eo21]

same here

[@simonallan9941]

Maybe you should have had both pistons at the top like my Yamaha 650 twin 🤗 makes it sound like a Triumph 😮, that is one exhaust and one compression stroke.

[@Игорь-з1е5и]

Чëтко, эти движки очень уневерсальные, доктор маладец.

[@roberthpareira8510]

Amazing..

[@TrungTheMaker]

you should totally build a double wide mini bike

[@lauriperamaki5354]

Amazing. With you skill you could make something even more incredible

[@Midnightrider773]

Very cool, your very talented 🔧

[@theprisonernumbersix996]

Tres bon travail , bravo !

[@CalixtoCartilla]

Thats amazing job

[@philcrittendon7287]

I took the governor off a small engine once. I'll never do that again. Those cast flywheels will explode.

[@thorstenschreier7891]

Nice work.Have the same engine at home.Very interesting to me.

[@gmoac]

love the sound

[@aklana96]

Accurate number 99 top...thumbs up 100% cool my boss...extraordinary great

[@pyndapnk9466]

Excellent job bro 👍👍👍👍

[@elmarko9051]

Cranks are designed to carry power, among other things...would there be an issues with too much power snapping the crank if the motors are too heavily loaded?

[@ColorfulWorld-kq4lo]

Wow...your a master..😊😊😊

[@vladim473]

Привет!интересное решение,лайк 👍.это будет новый безумный картинг?

[@denda88]

I'm from Indonesia. Very impressed to see your ability to create

[@arthurdombroskie3083]

Try the crankshaft 270 degrees apart

[@robertciganovic965]

Wow great video

[@goranilic183]

Bravo majstore veoma mocno zvuci tvoj duo motor!😂 Imam jedno pitanje kakvo izkustvo imas sa Einhell tp-cd 18/50 li-i baterijska srafilica, uzeo sam sebi jednu za kucne potrebe, pozdrav!

[@StarDust-zo8gd]

Za kućne potrebe ili neke hobi stvari može proći, baterije im nisu nešto na kvaliteti..ali to je to..hobi alat.

[@78dwk]

thats cool ,Great work Godbless

[@juankisaka]

Muy buen trabajo👍🏼 Has provado de poner los dos pistones arriba y alternar los tiempos? Felicidades👏🏻👏🏻