Відео

all the wizards and sages in s1 go karts that build their own and offer porting to mates have a couple things to say: u want the area where the spark plug is to be exagerated and the area around the edge as close to the piston as possible they port elephant ears in the transfer ports too seems to help a lot when u have low engine v/e down the revs, less likely to stall and bog boring is natural but they reckon if u overbore past 54.5 u are asking for trouble with port angle and height yamaha kt100s

Air-cooled two stroke engine! Very, very interesting!

Also, fill the holes in the crank webs with cork, "corking (or stuffing) the crankcase".

In my experience, raising the exhaust makes low rpm torque drop slightly but extend the high rpm. For a simple mod that gives a bigger difference, take 15mm off the piston skirt on the inlet side. My 125 would lift the front wheel with just a twist on the throttle.

Could be interesting to saw a exhaust in half and add acrylic layer to it to show what's going on in the rest of the system

1year ago then the result of the test under real conditions after .

well at 600 C the test that will show.

Looks super generic

All hail the w ite English bloke , inventor of EVERYTHING. unfortunatly I cant get all that on a usable chain saw .

yeah man iv always fancied seeing a 2 strokester tuned to the eyeballs

Had no idea the ports were so BIG.

I once worked for a guy who built his own inertia engine dyno for only about 3 grand. It was about 20 years ago. He used software from a company called 'performance trends", and built the direct drive dyno and mounted it in a piece of 1" thick aluminum jig plate (ground flat on both sides is jig plate), and he used it for 26 cc model gas boat racing engines (a engine he was developing, but never came out with.). I used it when starting my business, and it fit in the front seat of my car. it was simply an engine mount hooked to a drive cable (could use shaft), into a 4000 rpm centrifugal clutch, (used on 1'5th scale gas rc cars), into a disconnect "in shaft" devise that he designed (clutch size, 2 piece that disconnected the flywheel weight from the engine when you let off the gas), and to the flywheel. If you do the math for the flywheel inertia, (small diameter so high rpm will not blow it up), it will be very accurate, as there are only a few bearings in the drive shaft system that are not included for drag. The engines I started working on (Zenoah G260 engines) has a manufacture claim of 2.8 hp at 12,000 rpm stock, with no exhaust or air filter. After I jetted the carb as well as I could, I measured that same stock engine on that dyno to read 2.78 hp. I can do a lot of cool things with my water brake dyno that yo can not do on a inertia dyno, but I have to say,---that thing was accurate and repeatable to a degree that most dyno's are not.

The most advanced engines are those of racing scooters. With the exhaust at less than 200° they easily exceed 15k rpm. The main performance is made by the shapes of the transfers and their total area. If you are looking for maximum performance, the cylinder and the exhaust are the ones that dictate the law. Surely you already know that

I started thinking who is this chop but now i am humbled sir thank you

Love vic Reeves as Russ mael from sparks👍 ( is it Ron mael ?)

Matt at bdk is the guy

Been missing your videos, sorry to hear of your dad's passing , look forward to seeing this come together, should be fantastic.

Good vid! This may be ok with this small bore motors with no power valve, however be cautious with your dirt bikes that do have power valves. For my motocross bikes I always liked to clean the casting flaws and polish the exhaust port to a mirror shine, without changing the deck height or the port height which affects the power curve timing. Exhaust port polishing also disallows carbon to build-up as easily. I would also make sure that there’s no lip at the exhaust port flap/valve that could deflect air. Make it smooth. This basic modification really helps with low-end torque without compromising the midrange or upper power curve in relation to HP and Tq. I would also clean the casting flaws at the intake side and the transfer ports, however, I would not polish these parts but you can, just remove the bigger casting flaws that you can feel with your skin, or flick your fingernail off of. In addition, if you ever have the engine apart with crank removed, it’s a good idea to be sure the cases match the cylinder head (case matching). So basically what you want to check is be sure where the cases line up to the head and there’s no lip that can be felt to the touch, or you can flick your fingernail off of. Basically, anything that can deflect air get rid of it. Be sure to trim the gaskets too if they overhang any airflow or air transfer areas. Gaskets defect air too if they overhang into areas they don’t need to be. Here’s some good advice… If you really feel like you have to mess with the port height or shave heads try this first. Install a thinner base gasket which will drop the jug creating more squish, and dropping the overall deck height which lowers the exhaust and transfer ports, let’s say 0.015” (15 thousands of an inch) for example. Start there. In addition, I always like to use Vertex pistons and rings for a few reasons. Vertex pistons typically have a coating of molybdenum disulfide (MoS2) on the piston skirt, which acts as an anti-friction coating to aid in the break-in process and reduce wear during operation; this coating is often referred to as a "hi-tech molybdenum disulfide" coating in product descriptions. Vertex's latest generation “piston rings” are nitride coated or chrome plated, increasing wear resistance and extending durability. Also, Vertex “pistons” have pre-drilled hole or holes at the exhaust side of the piston that allows oil to flow through the inner side of the piston to aid lubrication at the exhaust bridge. Small bores such as the one in this video may not have an exhaust bridge, however a larger bore two-stroke probably will. I’m not a pro engine tuner or builder, however I know how to build solid good running motors that run for hundreds of hours with great reliability and smooth operation. Lastly, always use bearings that are Made in Japan, Koyo bearings are a good option.

The larger LA Sleeve will help with that and ypu can finish port the transfers much easier

Still doesn't behave the same without a head on there there's something called Scavenging which cant occure unless their is a head

Just thought, I've never seen tangential grooves in a 2 stroke squish head and I wonder if they would improve combustion flame propagation by creating horizontal swirl in the clearance volume gases. They probably only need to be 20 thou deep in the squish band. Worth trying?

...always wire feed .25" flux core, my pipes . Weld left to right and stay on top of the weld, stitch welding. No slag. inside no leaks .( oh yeah, gusset the stinger or they,ll vibrate off from pressure/ vibes. When you get it right you'll know because the power (range of useable power will astound you, and the exhaust note, (tuned exhaust) will deafen you) Best of all things to you. PEace grd

...sorry, you cannot, "Sneak up on it," it must all work together, but again, exaust port should be raised, not bizzarely widened (more area than the head pipe is pointless). Raise the exhaust, to race power spec (24mm From top os cylinder on a 220 cc cylinder, the exhaust restriction will literally act as a blower, to boost power. When it works, nobody will touch you. ( It's true) Again it's been fun. Thanks and PEACE GRD again,jet it fat, I ran 740 main jets w/ 7DH2 needle, in 46.5mm Mikunis.

Aku selalu memikirkan water injection, pasti seru memanfaatkan panas mesin untuk menambah daya dorong piston, hemat energi dan lebih bersih 👍

what is this "MSV" ??

Great video! Greetings from Greece. So i started experimenting with 2 strokes. There is an app on Google play that helped me a lot. I don't know if you know it it's called Engine calculator Pro. Its worth checking it out. Keep the good work!

Don't toss the heads ,I will buy them off you ! REPLY !

muchas gracias por no dejar morir la pasion por los motores 2 tiempos

I have a Honda PXR with various bigger barrels like 65cc Athena,Zeta,Polini but a proper exhaust is hard to come by off shelf so I took a Proma pipe from a Honda MB5 and welded it to fit the pxr and boy that pipe made this thing pull :D .also had it on a Honda MT5 with Malossi.it gave more torque than any of the other off shelf tuning pipes. exhaust design is very critical on 2 stroke ;)

Apologies to tthe DT80 guy who was in the live chat. I was gonna try designing an expansion chamber based on 125LC port maps and timings but there's gonna be far too much guesswork for it to work properly.

whats the 'pipe' called at 14:00

Mike.......some sort of 2t Jedi master

Which correction factors except for ambient temperature and air pressure do you use when running the dyno? It can give big difference comparing tests from different time of the year.

What is MSV?

What about a thinner base gasket ?

the first top with high compression 14/1 is good if you have an expansion chamber the pipe should be 32 mm inside soft bend down or up goes to a strut that is 32 mm inside big side 95 mm inside this joint should be 760 mm counted long way from the piston counted outside expansion chamber middle rear cone should be 95 mm inside 250 mm long cone 27 mm outside tail pipe 220 mm long 18 mm inside end silencer is mounted on it! intake 70 mm long 26 mm carburetor the intake should be narrowed so that it is only 9 mm high 34 mm wide the last 12 mm should be the size of the intake on the cylinder this system makes high speeds in the intake and exhaust chamber close to the speed of sound 1200 meters per second the carburetor will get so cold that ice forms -cold lye makes many horsepower -have pulled off the drive shaft the drive outside many times 50 cc 187 km per hour larger engine volume up to 250 km per hour

what exactly is the red mold stuff?

Infinite thumbs up

For testing could you not space the jug up the amount you want to raise the port then mill the head. to get compression back. A head is easier to replace than the jug.

Does ur lathe not do single point threading?? Only standard threads?? Or you haven’t gotten used to it yet?

tagboard and tin, G@d that brings back memories, before my retirement. PEACE thanks for sharing. Fun Watching. GRD

...water cooled cannot run as high a compression, the head gasket won't take it.Have you seen the 50cc-100cc, drag bikes run mid 9's? (on you tube) I beleive it was right at 100 mph, again 1/4 mile so your goal is very do-able. With proper porting, raise the transfers and exhaust, if you have reeds on intake you can still lower the port. The reeds limit ramming force, but my YZ250 was as quick , and as fast as my 750 Honda, bone stock in a lightened frame, and it, the YZ, was reed block, with slick in custom lay down frame ( I don't care for reeds, but cast my own head to get the plug back to the middle of the chamber). Don't overdo the compression (size of the chamber), but squish is essential to efficiency. Best of luck to you, PEACE GRD

Just found your channel, your videos are really well done and you’re doing all kinds of creative things, very cool. Well done! How’s the bike running these days? How many MPH are you up to? I did something similar as a kid with a minibike, it was a 4 stroke but I slowly got it from 23mph all the way up to 67mph from ages 13 to 18. It was so fun, still have it, hasn’t made noise in about 15 years at least.

Are you running a stroker if not think you need to watch a lad from USA Monzboys he got a tiny scooter CBT clutch doing 99mph it's insane the speed of it

You have got a lot of material to open up that bore

Have you ever had a go at melting Aliminum and pouring it out to make Aliminum rods /bars for rewelding the heads back up save scrapping them there's some very good videos on UA-cam there are Indian/ Pakistani that to it you would save a lot of money 💰 may be worth having a look into