for all those who are curious about the link, forget it, it's a broken link which brings you to a page that isn't even related to this guy's channel.

While im not a two stroke expert, im trying to learn some stuff about motorized bicycles before i build one.....and all i see in the comment section is... "your doing it wrong"... so i went to there sights to look for there 2 stroke engine work and all i saw was videos of other people doing stuff ,how to get through video game levels & shit....trolls...good work.

Remember these are crude chinese engines and his port work od excellent. This isnt rocket science. Stop hating.

hi i just wanted to thank you for all your helpful advice.. this video helped me gain 10 mph.... i did exactly what you suggested with the exception of deburing the transfer ports.... i only had a file at my disposal....

I would like to see some examples of these mods running.

The best tools to port with are from FOREDOM. There is a company called C & C enterprises who sell all the porting tools you'll ever need. Start w/ a 90 and a straight. I have been porting all my adult life. I have set 14 Land Speed Records on small bore 2 stroke engines I have built. I 've done karts, GP Road Race motorcycles and am currently doing drag race V8 engines. It's a good idea to study the mechanics and theory on how the gasses flow through the engine. You need to get a real grasp as to what happens in each port as the crank turns.Do the gasses flow front to back or back to front? How to build a pipe that is going to help you achieve the powerband and over rev...porting to that pipe. What about the head and squish velocity? A good pipe and good head work...along with jetting the carb correctly will net you more power than a port job. The porting is just icing on the cake. I hope this helps. In college, I studied flow dynamics. I fell in love with physics from 2 stroke motor building. Good luck! And chamfer those ports!

I find that porting and polishing does increase overall performance based of of my own personal experience and the videos I’ve seen on KZfaq. Another benefit to these motors would be to ensure that the cylinders have been honed for a more advanced oil saturation on the metal surface to increase overall lubrication since you’re increasing the surface area by using a honing device.

What a fine tutorial on 2-stroke porting.

Your knowledge is so extensive it is RIDICULOUS.

Great video, but " Taking meat off the top of the piston" Squish is mega important and so is a crisp edge on that piston to control port timing.

Come on guys. Cut him some slack. I get the strong reactions but who was perfect the first few times? I fully understand its best to be precise and have proper tools. However give credit where credit is due! Hes at least trying. The difference between my first build and my 3rd and current build is unbelieveable. Some of us are self taught. Take it with a grain of salt. Or leave it. Better question why did you finish the vid then waste more time leaving mean comments? I may be female and self taught but i bet my bike is faster than yours!! ;)

Thanks a lot Daniel! Means a lot to US and we are always glad to help out with any problems you may have! Good luck!

lower the in take raise the exhaust ramp the transfers and chamfer to avoid ring breakage buy the window piston and the reed cage

Holy [Bleep]! Get Juiced! I final wash jugs (especially 2 stroke) with scalding soapy water. It dries fast. Pistons too! Two Stroke is Heaven!

Measure from the bottom of the stroke to the top of the cylinder. The top of the exhaust port should be lifted to about 2.5 mm under half way. Do Not go to half way !. The flatter the top of the exhaust port is the better but for longevity it is a compromise, so keep a little radius here. Lift the transfer ports by the same amount that you lifted the Ex Port. You can if you are able to do it, make the tops of the transfer ports where you lift them into a Y shape. When your engine starts to crackle you know that you are on the right track. Loads of experimental work here. Loads of work and expense as well. Make the expansion chamber out of thin material so it can "flex" under the + ve and -ve return pulses. Return pulses at high revs are supersonic so get your ear protection on !!. Good luck.

I believe i saw one of those before on KZfaq. some guys made a prototype with two carburetors wired to one throttle. It was pretty cool.

you have one thing mistaken: although making the intake port rough will increase fuel atomization and may slightly increase efficiency, it will actually hurt power because it decreases volumetric efficiency (breathing capability) of the engine

Thats a nice trick.....with beveling the pistion and cutting out portion to increase fuel delivery.....Id like to make the changes when I put my new piston in after some use.....

If u want to port make sure to also stuff and flow your case. Also index the spark plug.

hey man the link doesnt work?are you able to fix this.really keen to do this

Something that needs to be looked at if you are going to do any porting or casting flaw touch up is to port match the intake tube to the cylinder. On a lot of those motors the intake tube shape and port on the cylinder don't match, killing the flow from the carb, rendering a lot of the work to the cylinder ineffective. And port match the boost ports to the base gasket match the gasket to the ports on the engine case and then match the boost ports on the base of the cylinder to the gasket

Wow, this guy is a genius, I anticipate a comeback of two strokes due to the improvements that this one person has made towards an otherwise defective engine (obviously manufactured by complacent hacks). Is it possible that he has deferred from NASA to pioneer in his own expertise (the blue gloves were a giveaway). Gremlins are the cause of the scoring in the cylinder and shoddy workmanship, also the cold and flu medication he is taking is responsible for making him sound like he is completely clueless. All that aside, the man is truly advanced in 2 stroke engineering.

I'm learning too. Thank you!! Good video.

at some point i will post my personal bike and it surely purrrrrrrrrs!

just a little porting makes magic 💥💢💫✨🌟

chamfering the ports and the skirt of the piston on the induction side will also will rising the compression by having the head skimmed also might be worth finding out if you can get a reed valve set a tuned exhaust would help a lot

it's the best vid about the porting that i ever seen

Lol people are so butt hurt about this video. Complaining about everything. But people remind yourselves! These motors are $100 from damn China....... Anything you do is going to help increase power and efficiency. These motors are not freaken Porsches.. they are dirt cheap toys.... They don't need rocket science to run better.....

dont take anything off the crown of the piston... bad bad bad you have just unbalanced it, do it all via ports.same as the skirt.. it provides stability on a 2 stroke piston. intake ports should be smooth, you want to reduce turbulence in the ports. the a/f mix hitting the crank counter weights is more than enough atomization. if these cylinders were plated you would of destroyed them. if you guys want power, look into timing advance, REAL porting, shaved heads and bored carbs. then jet right and put a good tune pipe on it and your rocking.

just wanted to say thank you for postion this video the bike gained power all around and now revs more like a chainsaw than a bogged down P.O.S ......lol...... i look forward to any new videos you might post..... especially one of a running bike you upgraded and a top mph.

you can raise the piston to the top of its stroke and look through the cylinder intake and the piston ports will be slightly smaller. I take an awl and scribe a line directly inline with the piston, then I simply grind the piston port to the size of the cylinder port.

this is GREAT! thank you! Now our customers wont have to bother buying them from me, arrow motorized cycles, CR machine, or DAX! what a great thing you're doing here! and we wont have any work to do!! woo hoo! like a vacation from all that awful work! now, do you have a video on not having to continue paying our bills?

Very interesting. I can't imagine that I'd need more power out of my 66cc but it's still good to know.

do you have a video of building 2stroke bicycle motor to being faster

Right on thanks man! Now I wont have to dish out the cash for a jug from arrow! Haha

How well can the transfer ports be reached with such setup (dremel's flexshaft) and what tip to use when doing that? Ps,you shouldn't raise the intake port,you should lower it so fuel mixture can reach the cranckcase earlier :P

HEY THANKS 1 MILLION FOR THE INFORMATION MAN I'M ABOUT TO MAKE MY MOTOR BIKE STUPID FAST!!!!

Porting and polishing is very important in achieving a crisp rpm sweep in any high compression engine weather it be 2or 4 stroke the small pitting in the intake port can and will collect fule wich will cause premature defamation and if this occurs during the exhaust stroke this can lead to premature ware of the rings and cause blow by and cause bearing and or lower end of the case to become brittle and crack never remove material from a piston as this will cause week spots in the piston and more then likely cause the conecting rod to push up and threw the piston and can cause poor combustion cloging the intake and exhaust. Ports causing even more Los of power if u want to gain power there are dished pistons for these motors that will give you more power and best to upgrade to a exapantion chamber and go up a size or to in ur jet size also to adomize the gas just go to ur local hardware store and buy small fine copper mesh and use between intake manifold and jug with porting and polishing both ports will make noticble and reliable power

you can also deck the cylinder to

Great video, excellent attention to detail.

Dwainpipe 21 is right, raising the exhaust port lenghtens the exhaust port cycle.. and btw Dwainpipe raising will "always" give you more power ,but your right ..you can raise it so much, than you hit the limit of what your exhaust can correct.. and you lose compression by raising the exhaust port.. So there is a limit! And the guy complaining about giving secrets away.. boy i would not like a cylinder ported by your company..

personally I was just wondering about the transfer port casting burrs, 2 stroke have not been my forte I have had other engines that have similar castings but were made that way on purpose for swirl flow or hard roll fuel patterns weird but true. so this answered my question it is just crappy QC on the transfer port

Another way if your on a bug and don't have the tools for porting. Add an extra gasket or two to where the jug meets the crank case witch will raise both the intake and exhaust but then you need to save the top of the jug and head a bit so the piston come back to the top of the jug. I didn't explain that well sorry

Spot on Christopher

You should clean all your individual engine parts, with warm soapy water, before assembly. This will get all the dirt, dust, metal, and grease off; which prevents damage, and gives the oil a nice clean surface to stick to. Never use solvents, as they can penetrate into the metal, with several negative side-effects.

Hey, dude, you need to teach them jack the cylinder up via a shim between cylinder barrel and the crankcase and only clean the ports not raise them by cutting you raise the exhaust you must always raise the transfer ports too b y the same amount as you had the Exhaust by nearly half the difference this the real world facts, not just theory. Example: stock exhaust port timing was 155 and @ 102.5 degrees after TDC. Then you are raising the exhaust port to 180 degrees and @ 90 degrees after TDC. Stock transfer port timing was 77.5 degrees and @ 141.25 degrees after TDC, Then you raise the transfer port to 90 degrees and @135 degrees after TDC Getting these three to five ports dead on the money { respective degrees } is really super hard to do, all the while polishing these to not cause twisting of the piston ring causing fails on the piston anti spin pin, HEY Dude! You are Super lucky or you are the best cylinder port polisher I've ever seen. All in and said I've been doing ports on "Two Stroke Spark Ignited Brayton Cycle engine" some 20 years. And I have not been able to keep from spinning a piston ring at some time after years of trying I found taking up the cylinder is the only way not to spin a piston ring Oh yes the rings do have pins that keep them from spinning but that only works when you are really well experienced at doing the porting stuff otherwise it just keeps pushing on the piston's antispin pin until it loosens up and drops out now you've got a little pin floating around the engine if it goes out the exhaust port that three times air pressure and three times volume will, at some time or another push that pin right back in to the cylinder which will either hang a port edge smash into cylinder head and piston crown. none of these are good for engine life and the safety of the rider. I've had a cycle to lock up at high speeds but this was due to spark plug insulators breakage which was caused by the detonation also being the cause of not high enough octane but early on I had piston pins get loose and hang in the transfer port and piston this was a motocross track and was going about half T this kill the engine anyway. even bent the rod too. You want to test an engine run it while then look at the piston antispin pin in those ring groves if it is a good builder it will show "NO! WARE" on the piston ring ends right where the piston antispin pins contact the ring. If there is were there then the engines just do not last long either. This also the real reason the not use hard cutting stones hones on to cylinder rebuilds you must only use soft cutting stones on all two-cycle engine yes this means same types of diesel engines too.

but was able to do 90 percent of the things covered in the video.... i even widened the gap on the piston where it opens up for the transfer ports directly below the pin on both sides.... i port matched my intake and exhaust as well as widened my gaskets to better fit the flange for both intake and exhaust....

Nice job

So if gas go in crank case better make smood intake so fuel go easy in and lub parts when finish it will be atomized i think but we need to see some tests

Beware, carbide bits will chip nikasil off cylinder wall

The main benefit to raising the exhaust port is that it offers more of the spent exhaust gasses to be redirected back through the exhaust port allowing for higher dynamic compression.

Good info. And all in one take!

I wonder if raising the exhaust port could damage the cylinder at high revs per minute, as it gets so close to the limit.. I suppose you must not file so close to the limit.. Am I right, and does porting force the engine to use more gasoline??

Thanks for the info, and trying things out. Wouldn't an easy thing to do just be adding a bigger carb and tuning it? Like put an 80cc or 100cc carb on a 50cc engine, to get more fuel and open inlet port crossection too?

Then students need only to port the "inlet port" of "piston inlet ported engines" where you can grind and almost leave it in an unpolished state for test reasons until you have done then finish the polishing of the cylinder edges. This place is not ring touched In almost every engine I've ever seen. But always Clean the metal particles out before starting the rebuild your engine. For that matter just clean the whole engine's part completely, then "Do the whole Rebuild" completely.

Hey man that link in the description isn’t any good anymore

Instead of modifying the ports I would just shave a little off the bottom of the piston so the ports are actually exposed all the way. Messing with the cylinder seems overkill and you can easily lose compression and ruin the engine if you don't know what you're doing.

read power tuning two stroke engines,.....it will explain all

If someone did this to a true race 2 stroke I would cringe. I'm not sure if air cooled weedeater engines are nikasil plated, but race bikes cylinders are. You round the port edge at the cylinder side and you're going to start running into HUGE problems.

subscribed. first video thats actually taught me how to port and polish the two stroke. ive got a 1990 Yamaha RX-S 100 that i want to chop down and modify into a dual purpose scrambler/cafe racer. do you know anything about modifying forks,swing arm. upgrading shocks and raising seat height?

first of all you NEVER raise an intake port you lower it. secondly you said raising the exhaust lowers the duration that its open that's backwards. you can raise the exhaust but you should also widen it. look your reading and learning but you have a long way to go so please don't be giving people advice until you learn more and really know.

Hello I need help! The kit I purchased won't run right. I took off head and noticed that at BDC MY INTAKE ports are not visible. Is that normal? Did the wrong piston come from factory? I have the low hole piston. I can't find information on intake ports and BDC. Or pictures of BDC with piston relative to ports position.... The motor would start but not rev past 1000rpm felt like it was starving for everything.....

A few comming out in the upcoming week or so. Stay tuned!

Thanks for the video, great info. Keep up the great work everyone ☆☆☆☆☆☆☆☆☆☆☆☆

so u can round it and piston rings wont get caught?

What kind of solder would can you use for a crank case bolt . One of the threads that hold crank case prongs stripped.

What are your timing numbers? What is the bore and stroke for the cylinder you are working on?

i had to cut off and file them flat on the bottom of the jug to make it fit onto my motor, should it still work? it will only fire if i dump gas down the carb :(

Hey um wouldn't grinding away only one side of the piston make unbalanced which would result in wear and tear of the piston walls and rings? What is your opinion on slipper pistons?

what do you think about Lucas 2 stroke oil? is it really better? thanks, Great Videos. I liked and subbed, and viewed about 10. very informative. i'm the only one on KZfaq with Wheelchair wheels on a motorized bike.they work incredibly well. 8^)

You how to asssebly that exhast

whats the correct porting and upgrades needed for perfect hill climbing? (45º hills, rly steep ones) i wanted my 66 to be able to climb a hill without pedaling, in which is not the case, it cant in standard factory state

Thanks. I have a extra motor laying around. is it okay to use the top ring only? (I broke one)

listen my bike is running extremely good on the top end but my take off is kind of sluggish can you advise me on my next course of action to fix this please advise

Do i need make a third transfer port on the cylinder for my rse reed valve setup and windowed piston?

what is the song at the start? i like how it sounds!

I notice you are using a GT cylinder I only use the GT5A that has a 40 mm intake bolt spacing and a matching reed kit !What is the torque you use to torque down the head ? I was hearing 120 inch pounds and 80 inch pounds for the aluminum Fred head . what do you torque your heads down to?

Thank you

I'd like to see some work done,,,

great job.

Good work

very informative video ! great thanks

want to hear your opinion on this rod to ZMN80 I never seen one of these rods you know anything about him I got one on my engine

This is kinda like watching my toddler try to explain trigonometry lol

Awesome Info..Thanx Bro

Great tips, I LIKE IT

what if transfer port wall break

"Raise the intake port"....er no, if you want to increase the intake duration you need to lower the port. Having said that cutting the piston skirt like you did will increase the duration, not that you mentioned this. I think to sum up this video I would say that you don't have a clue, put your tools away and go and find something else to do.

When replacing the piston on a 49CC engine, does the "3" on the top of the piston come closest to the Exhaust Port?

guys, like what you are trying to do here, but looking at your cuts and work you need to pay a bit more attention. I know these are cheap cylinders, but the work is sloppy. There are also a LOT better tools out there than what you are using. Raising the piston skirt too much on piston ported cylinders can cause flooding at lower rpm, by letting the air fuel mixture do a double pass through the carb. And, no that is not how you chamfer of bevel the port window edges. You still got a lot to learn, but keep at it, experience will bring knowledge.

is widening the exhaust port going to make the piston ring dilate and gaught into it??

+JuiceMotoParts what if your exhaust port is round?

Next engine honing?

Great vid G

Wouldnt that unbalance the piston?

sounds good to me

hello is true when you porting you always go down never up

je l'est déja fait sur un peugeot 103 vml de 1985 , agrandir les transfers , l'echapement , admission , mais il y a des cotes a respecter , poncé la culasse a 1mm , carbu de 15 , pot sito chrome , 95 km/h elle a toujours fonctionné , essence huile 6/

so which side is it? exhaust or intake ....... ??

Can u plz tell me what the number on the piston means mine has a 3 on it ....i need to replace the cylinder i wanna make sure to get the rite stuff ....its a power king kit ....