Why all negative comments? Kids trying different things. Engines are cheap. He is figuring how stuff works/ and what doesnt. I give him props!!! 90% of the fun of a 2 stroke is modifying them and see what happens. A+++
Son I must correct you on something. Cutting your piston skirt that high hurt you more than helped. You are looking at more flow entering the engine because the skirt is not restricting flow coming in to the lower end of engine, well fine. But what you are forgetting the piston skirt also closes off the intake port to keep the crank case pressure high. What you are doing is blowing the extra fuel air mix out the intake port on the down stroke. That is why the factory racing piston is not cut as high. Those guys know much more than you. Try raising that skirt around .050. Believe me on that, I worked for Yamaha racing for many year. But I like seeing a young man like you applying your thinking on stuff as this instead of playing computer game s.
Mr Fitzgibbon, I started my engineering journey as an apprentice, now only 30 years l am still learning, I am glad that my mentors had the same understanding as you sir, and ALL that make a comment here, should read yours First. 🕎🌎🌏🌍✝️
No mention of upgrading the brakes on his bicycle. A friend of mine installed a lawnmower engine on his bike. It went really fast, but didn’t stop so well, which was not surprising, since it had bicycle brakes meant for bicycle speeds. Anyway, he loaded his girlfriend on his bike and they went for a ride. They got going pretty fast, but when he was unable to slow down in time, he hit a parked car. He sustained some permanent brain damage, and his girlfriend was killed. If you want to go faster, learn to pedal faster. Then, if you still want to go faster, get a bike with brakes that can slow from those speeds. As for using sandpaper to remove noticeable amounts of material from the head or cylinder, those are mated surfaces that have to be very flat in order to seal against the high pressures in the combustion chamber. To keep the flat surfaces that the engine came with flat, proper machine shop tools are required, or at least use a piece of very flat plate glass to put the emery paper on. That will be much more likely to give you flat surfaces when you’re finished.
Mirror polishing the face of the piston and combustion chamber helps too. Especially when you're running high compression. It resists carbon buildup, which will keep your compression from getting too high over time, and it'll help prevent pre-detonation (pinging/knocking), by preventing hot spots. It also think it makes the engine run a little cooler, because it reflects heat, making more of it leave through the exhaust.
Don't use a windowed piston unless you have a reed valve... For the piston skirt a couple milimeters is probably fine but too much will make it just send fuel back out through the intake. At least pistons are super cheap so if you do get it wrong you can easily start again and dial it in. This is definitely how you learn what works for two stroke tuning, experimenting and trying all kinds of new ideas.
I'm glad RU-vid didn't exist when I was at this stage of learning, your getting there bud go buy some books on engine blue printing and porting and polishing
hi mate, the windowed piston is for applications where a reed valve is used on the intake. it gives the intake more duration but is no good without reeds.
lmao no idea what youre doing.. destroyed the squish band.. modified piston skirt without reed valves... pulse/diaphram pumper style carb requires a vacuum line that is tapped into the crank case. those carbs absolutely NEED that vacuum to operate the diaphram.
you have no idea what the fuck your talking about. you don't need reeds to alter port timing. reeds don't make power, they "make" throttle response. pumper carbs have the pulse fitting in the intake. you're basically aa moron that thinks 2 broke surfing knows shit. he doesnt. neither do you.
I have done various upgrades to my 80cc 2stroke, the dual window piston, 3 prong hot spark plug, bbr tuning high performance cylinder head, high performance carb with air filter. I added a boost bottle to help save fuel which thats all they are useful for xD, I also changed out the stock chain tensioner, and got BBR Tuning Billet Springer Chain Tensioner. Added a sprocket adapter instead of those trashy rubber stuff. Took out the stock hand brakes and switched over to blueshine MTB BB5 mechanical disk brakes. took out the stock exhaust and replaced with bbr tuning HP thrust F2 exhuast. being I added a boost bottle, I had to change out the intake manifold to one that had the inlet plug already placed. removed stock CDI and added a HP CDI. and to top it off, threw away that pointless .5L tank and got a 3L. next I will be thinking of doing a a change on the clutch flywheel
At least you tried but you clearly don’t know what your talking about. Just don’t talk if you don’t have knowledge to talk about. The thing is sanding down the head will give you more compression but create more heat and is more prone to engine knocking. With 87 octane fuel higher compression is dangerous to your engine. Everything you said about pistons is false. Windowed Piston is useless without a reed valve and a diaphragm carb is ridiculous.
Clearancing the piston on the bottom does nothing because air and fuel isn't drawn in on the bottom of the piston, it's drawn in on the top were combustion takes place. I get that you're trying but really..... know WTF you're talking about before making a video to inform or should I say misinform others. Anyway keep it up and eventually you'll get it right. 😁👍
I’m currently experimenting with a flat top piston and it’s excellent on paper but I still have my doubts. I can always save up more money and buy a piston in case I mess up but the ideal piston for these motors for me (without any scientific data) would be one with a skirt, a window or two on the intake side, and or a flat top to prevent blow by. If I were utilizing the videos I’ve re-searched over again for video comparison, I’d probably ad a ramp but I’m still looking around for information on the topic to increase overall power.
That Walbro type carb needs a crank case pulse to make it pump fuel. Somewhere on the engine side you will find one. Unless there is one on the carb body, you will need to mod it. You need to drill and tap a hole in the crank case and install a fitting to get that pulse.
1.) Windowed pistons are for use with reeds...the bottom of the skirt makes no difference at all as the windows keep the intake port open....without a reed then yes milling the bottom of the piston helps as it uncovers the full intake port at TDC allowing in more air and is also helping increase intake port timing by as much as 10 degrees. 2.) You absolutely destroyed your cylinder head as you completely ground off an important thing called the squish chamber...I highly advise against doing what he showed in this video with the head. The Oko carb is a great carb for use with the Dio Reed set up...it is not too big for such a set up but is for smaller or no reed set ups I'm sorry but this is not a very a very informative video on improving power.
Michael Hitt relax the pistons for the dio reed if i eber get my new cylinder lol, and the squish band was just widened by sanding down and befor it was ruff and uneven now its got more compression and a tighter seal
No...the squish is gone...all you have left is the chamber. The squish band is actually 44mm on a stock cylinder and not proper for use with a 47mm piston...you completely removed the squish band...if I could show you pics on here I would..you'll be sorry if you use that head in more than one way...good luck to you👍
100s don't have heads so you might have to check out the inside of the cylinder for lumps smooth everything down make sure your Pistons in correct they always come in backwards if nobody knows
Do it to the cylinder as well intake on the bottom mostly outtake on the top round off all the corners smooth off the top before you put it back on Sand it if you have to
Gas goes in under the piston and is fired downward to bottom dead centre and pushed up through the transfer ports to the top of the piston ready for the next cycle .. these bikes don't have a valve system they work by transfer ports. Anyways he is right with that bit. But the rest of it is a bit questionable. Fair play to him though if it feels faster to him then it worked. I'd suggest a nice expansion chamber exhaust, properly ported cylinder and don't mess up the port durations, and a nice high compression cylinder head with a hp carburettor. although none of them are free.. but then there's no such thing as free horse power in the real world.
Man I can't believe hard comments. Wow you have a horrible audience. Whether you're right or you're wrong either way you're learning you're having fun and you're staying out of trouble.👍👍👍👍☝️
Absolutely. Nice commentary, trying things out and learning. He's spot on that the 21mm carb and reed are too big. Jennings 2 stroke tuning book is old but relevant for this type of engine if anyone is interested.
Agreed on the learning factor I do not discourage him for that but u say come on people when he has ZERO knowledge and everything he said will mess up anyone’s engine who tries this.. not to mention flat out LYING as if trying to get people to destroy their engines on purpose!!
I like what you're saying already did the same thing but put it on a 29 inch bike you ought to try 29in I'm telling everybody don't knock it till you try at the top end amazing
No need to heat wrap that close to the exhaust port. Windowed piston only works well with reed valves. Even with a further down jet the 28mm oko is a waste of time. It's simply too large.
Those holes in that piston does a couple things. The first being its lighter . The second being increased intake charge & lubrication but without a reed for timing the intake charge they dont work . Reedless 2 stroke engines dont use ported pistons This kid is incorrect about a bunch of his comments but he will learn just like the rest of us
MATTHEW STEVA, as an automotive technician, my training tells me that a ram-air intake should actually hurt performance. It reduces vacuum the faster you go, so your engine will run leaner as speed increases. The reason why you're noticing better performance is probably just because that intake is much less restrictive than the one you replaced. A high-flow rear-facing intake is the best you're going to get.
Get a shit chrome,steel hub rear wheel ,then weld sprocket to it, also my Dawes frame has no need for horrible chain rerouter, that make bad vibes, also rubber mount exhaust,these three things will make your bike not fail, probably catch fire instead !!!
Yeah, he doesnt know what hes doing, but at least hes doing something. It is way more fun to try stupid shit on your bike that doesn't do much than it is to just let it sit there. You dont learn unless you make mistakes, he should be encouraged to try more stupid shit.
On 2-stroke engines the gases are pulled through an inlet port under the piston, then cycle through the crankcase.Then on the down stroke, as the top of the piston drops below the opening of the transfer port the gases enter the combustion chamber. Then as the piston rises on the up stroke compressing the gases the bottom of the piston passes the inlet port allowing new gases to enter the crankcase.
Im not trying to be rude or mean but when you say that the windowed piston doesn't help with anything your wrong! By removing material it lessens vibration on the high end. Also with reed valves there is an additional bennefit as well! Like i said im not trying to be mean or rude. Trust me im subscribed and enjoy your vidios!
no such thing as free hp unless you have the tools already for a good port job , and you are 70% wrong , that certainly passes the threshold for keeping this video on your computer and not posting it on the internet
Caden Braun the piston is "out of service lol" its just for demonstrations i wouldnt use it the way it is, but shaving the head creates more compression and more pressure inside the motor= more torque and a lil power
I'll also add that with more compression means more heat, which means it's good to run a rich mixture (in a 2 stroke), for 2 reasons... the excess heat means you want more lubrication to protect against the friction of the metal expanding (and in a 2 stroke, your lubrication is through the fuel), and likewise with more heat you want more oil available to cool it (again, the oil is in the fuel).
by sanding the top head back you loose compression only sanding the block you gain compression u can can compression with a fater spark plug or longer one
Jake Tsaikos you don't it's only if you shave the middle down but if you shave it all over your spark plug will be closer cause more compression, sometimes I don't explain myself properly, English isn't my best subject.
Dirt Boys umm no it goes under the piston around the crankshaft and up through the transfer ports then ontop off the piston thats why the pistons skirt is shave so more gas will end up on top of it
I would highly recomemd doing proper research before doing ANY of these mods.. the gentleman in this video might not know as much about 2 stroke engines as he thinks, thank me later :]
These chinese OKO Carbys are nothing but rubbish and are not made for 2 strokes. Fact of the matter is, they 4 stroke your bike and refuse to reach the optimal top end powerband. Mine came with these two Jets that were just unnessesary and would give you no control over your idling and the Air + Fuel mixture was impossible to regulate and contain. Stick the the simplest of carbys starting from the stock Black Cap or Performance Red Cap. Most extreme i'd be going would be the Dio Reed Setup souley because they provide you with everything you need in the kit.
A young man once hollered at my daddy... Old man I've been doing this all my! My dad asked, how old are you son? He replied 18! He was laughed to scorn!
Can I ask you a serious question why would you do so much work onto a Magna bike Magna is such a piece of crap I'm being honest getting old bike with a real chromoly frame you'll be happy
Yeah TRUE But I suggest you go to Craigslist and buy an old safe and stable bike my bike that I rode for 4 years every day was a Taiwan built kuwahara and the frame never failed I'm over 200 lb and I of road a lot
