RC-One : Port Matching And Smoothing The Cylinder, Cases And Piston : RC1 : Part 03

[@Benjamin-xv2hg]

Won't lie about 2 years ago I came across your channel trying to learn about scooters. And to be honest I was like who is this nerd I just need some simple info. We'll I am back and very thankful for this nerd as I am trying to get a bit more power out of my scooter. There is a whole bunch of just let's try this part in my scooter. Thanks for actually going into detail, just here to learn more about small engines.

[@49ccscoot]

As I've told many people, you can skip or fast forward as needed... but no button will put info in that's not there.

[@matthewmoilanen787]

As a former designer/drafter I can tell you that with all case castings like that there are "allowances" that must be made during the casting process. That is why tuners like you can do some matching to eke out those final little power gains by matching the parts together. You would be surprised by the amount of shrinkage (yes I said shrinkage) that must be allowed for in aluminum castings.

[@oimpastato]

Believe it or not, this video helped me with a 80cc engine. Granted it’s a different engine, but the principle of porting you had shown also reflects on these engines too. So thank you for that.

[@49ccscoot]

If you haven't seen it, maybe check this one out : kzbin.info/www/bejne/jpTKd3xvZZqIfbcsi=u8jDeHfLNn0TsYmL

[@ryandeweese363]

Nice video man!! I have a yamaha 1977 400cc 2 stroke I'll be doing this stuff too, after new bearings and seals... in 77 they has some pretty knarly castings so there is deff room for improvement!! Thanks for the video, super thorough!!

[@kylevoss208]

I'm about to dig into my son's kx65, and this video just gave me confidence thank you

[@zamilnoor5736]

thanks for your teaching

[@MX-fo2nu]

Very good and akkurat done, i do it very close to yours, that works good for all as base or top improved.

[@Jeekinz]

The proper way to port match is to assemble the case halves to the cylinder. Then remove only one case half, this will expose the case to cylinder porting. Blend those ports, assemble the other case half then remove the first case half you just modified. Blend the second case half to the cylinder. Also, assemble just the cases together and blend them to each other. You may need to use dykem (sharpie) for other ports depending on the design. Do not base the port matching to a gasket. Match the components, then modify the base gasket to fit your engine.

[@julianjennings4638]

Those "grooves" or machine marks will help with fuel atomization, just before the piston cloases the transfer ports. "Supposed to" create turbulance in the combustion chamber. Thanks! Great video. Try coke cac tube shims around studs to minimise movements. Or cnc studs

[@4wdglampingaustralia102]

I have just watched every vid since the 86cc build beginning. Being new to 2Ts I have learned so much from your vids. Cheers.

[@49ccscoot]

Thanks for watching! Here are a couple before the TPR series that may be good for general info. 2T Case Porting/Trenching kzbin.info/www/bejne/jpTKd3xvZZqIfbc Compression Ratio kzbin.info/www/bejne/bmjEeYecrcanl8k

[@4wdglampingaustralia102]

@@49ccscoot exactly what I’m after 👍

[@meatcreap]

As always, an incredible and sufficiently in-depth video for a complicated process. Thank you! I have had the same experience with Malossi bores and other parts that I've received from them - the QC just seems like it's not there at all. When I first started modifying scooters, I kept reading that Malossi was, if not the gold standard for aftermarket parts, very close. So I splurged for critical parts here and there and expected a lot more than I got. I always chalked it up to either a fluke or just the fact that I wasn't buying from what I assumed was their higher quality racing line. It's more than a little disappointing that these problems persist even in their highest tier of products! My experience shows that the parts are very high quality but they cut corners on finishing for whatever reason. Negativity aside, I'm really excited to see how this RC-One turns out because you are committed to squeezing all of the potential out of these less than ideal parts -- and boy do they have potential! Plus, now this engine will feel fully *yours* every time you fire it up! Thanks again for all you've taught me!!

[@49ccscoot]

It's nothing awful, but some of it is disappointing. The ports may be able to be blamed on allowing the end user to match to whatever cylinder... but they didn't leave metal flakes and burrs around for our benefit.

[@gungho6798]

Thanks for sharing. Awesome info.

[@Lord_Verminaard]

This was very interesting to watch. I am also with you, surprised at what I am seeing for the price and prestige that comes with this engine. Not saying it's junk by any means, but I would have also expected better matching and finishing. The Stage 6 aircooled Minarelli 70cc cylinder I used was pretty much perfect, even though I didn't split the case, the gasket matched and there were no sharp edges and the finishing was pristine. And it was a pretty cost-effective kit. I was also expecting my piston to go all the way to the bottom of the transfers and it was a few mm above the floor as well just like your RC-One. I wonder if everyone that gets an RC-One does this much prep like you are doing. The port job you did was really nice, I wonder if you will make more power than advertised. I am enjoying this series very much, thank you for your hard work and showing every part of your experience.

[@49ccscoot]

Thank you. I can tell you for sure that everyone doesn't do what you're seeing here. I have looked at other people's RC-One stuff and seen some cases go together untouched. They still seem to rip. On the flip side, there are some folks I've seen overseas that handle a lot of Malossi cases that do beautiful port work. I have to imagine that with access to dynos they aren't doing it strictly for show. You can never say for sure I guess because it's being done for profit and how many porters mirror polished intake ports for customers because it looked pretty and sold well. All of that said, I'd have to assume that Malossi's advertised numbers are more ideal scenarios than just bolting it all up.

[@MarkSmith-rc8bx]

Hi Brent... Another very informative video. I wish I had watched this before installing the BB Kits in our scooters...Probably wouldn't have gotten into the port matching part of it but smoothing all those sharp edges seems like a great idea...

[@49ccscoot]

If an engine is assembled, you have to be really careful with port matching. Metal flakes in the crankcase are not so good. Stuffing rags in the crankcase is often used. Generally followed with flushing with gasoline or kerosene to be sure it's clean. Ideally, flushing with the engine out and the conrod toward the ground.

[@julianjennings4638]

Use kids plastercine or playdough for clearance checks. Oil one part, press the putty onto the other part and turn. Disassemble, cut the putth and check. Thanks again. Knife edge the fins?

[@svenodsvik569]

This is how you go about it. You could even take on a high reving 18000 rpm gocart engine. The only thing is angular timing ports and volume "crank vs schnurle port vs cc" . You´re getting close. Best regards.

[@warrenfranklin7579]

I'm watching this for information to take to a baja engine

[@noahsvejstrupharre6857]

where do you get your small burrs from? 9:55 ... my f***ing god, 2sek later you say that theirs links in the description

[@dinxsy8069]

KZbin is an oddity, i used to work for PMTuning in the UK over 15 years ago now doing Cylinder/case port matching (flowed carters) from little Piaggio Zip's to Italjet Dragsters and all in between. So strange how KZbin recommends this, out of the loop on scooter products, now Malossi has their own half cases. Ped scene didn't burn out

[@49ccscoot]

There are still some of us out there that love our two-strokes. The scene certainly isn't what it once was. I thought the four-strokes could be kinda boring, but now more and more people just want a clean simple electric that they never think about other than charging.

[@user-kr6si1pl7v]

When I finally get round to buying a cylinder kit n carnk Can I bringy draggy to u to port it loll

[@Harold1312]

PMTuning is the best!

[@Zuckrevo]

U need to get hired by malossi man 💯

[@realjohnjones]

Many small fixes create big end result brothas

[@LukasW74]

Great vid. Your relly relly thourog withe your stuff, nice to se. 👍

[@kuzixu4855]

Great vid 👍😁

[@progaragechinskiemotorki]

tyle materiału że jest z czego zbierać :D nie to co oryginał minarelli cpi itp. :)

[@velcrodreams178]

Dude your awesome !

[@popong_dtele1616]

Mohon pembahasan flow injection transfer port two-stroke mister I'm from Indonesia 😊😊😊

[@Team_Nico_Motorsport]

16:37 that is a common problem with the malossi blocks rc-one and c-one my race engines i also does the same thing as you do

[@justpauls]

Will port matching change the jetting requirement on a stock engine?

[@49ccscoot]

It could. If you're talking stock case and stock cylinder, then I don't think you'll remove that much.

[@franksavignac2788]

when gasket is moving like this.. i use to push it UP LEFT... tight on the bolt... so at the install you know that you just need to push it up left....

[@rosarioviola1045]

👍

[@IosuamacaMhadaidh]

B-dog is back, look out everyone! #scooterlife #49cc

[@cagr4249]

Also in case of this Malossi I wonder how "short" the cylinder sleeve is designed. I think additional 5 up to 10mm would improve the piston's life.

[@49ccscoot]

Possibly, but it's a tradeoff. It is a racing engine, and long protrusions would block some flow.

[@robertpierce1981]

Because I whined about the music in the last video I feel obliged to mention I noticed it’s absence inn this video. Personal preference. I prefer the easier to listen to dialog without filtering the music out. Since the videos lag behind real life I need to get onto the board and see where you are in this process.

[@SotirisPiloridis]

ΜΠΡΑΒΟ ΡΕ ΦΙΛΕ ΑΜΕΡΙΚΑΝΕ ΜΠΡΑΒΟ ΚΕΝΤΗΜΑ ΚΕΝΤΗΣΕΣ ΚΟΣΜΗΜΑ ΣΑΝ ΚΙΝΕΖΟΣ ΣΑΝ ΙΝΔΟΣ ΣΤΗΝ ΥΠΟΜΟΝΗ ΜΠΡΑΒΟ ΡΕ ΦΙΛΕ

[@Eduardo_Espinoza]

14:40 thx Hank :)

[@wanmuhammadfakhrullahwan8078]

👍👍

[@wiebrenvk8175]

3:50 “not the case” ha

[@AAs-vb7pv]

Are you going to do any allo welding brazing to graft different cillinder s and head s on engine s I'm trying to put a 500cc cr head on a lambretta case and need ideas lol

[@49ccscoot]

I doubt that I will anytime soon, but if you go on my forum and lookup member 190mech he has grafted MX cylinders to scooter cases. Stuff like milling the case and welding in an aluminum plate to be machined as a new base, mixing and matching bits to make hybrid cranks to get the stroke he wanted with compatibility for a variator, joining an MX case to a scooter CVT. No vids to my knowledge, but some forum posts. If you run into trouble or are looking for general help, post on the forum and he and some others may chime in. Sounds like a cool project and I'm sure myself and other 2T fanatics would love to check it out.

[@paulbudford]

Great vid as always. Is that you on the guitar track? 🎸

[@49ccscoot]

Thanks, and no. It's just KZbin Audio Library stuff that is allowed for use in vids.

[@dakine808shooter]

Awesome video. You ever build a honda dio? You'll port match alot lol. Can't wait till next video. This moto is going to be hammah!!

[@49ccscoot]

Thanks. Never built a Honda 2T. I've only watched them go together from some of the other guys on the forum.

[@dakine808shooter]

@@49ccscoot minarelli has soo much more performance parts hard to beat. But your a slave to that moto lol. So much up keep . Are you a teacher of the trade? Your videos are really that good. Can't wait for the next one bro.

[@49ccscoot]

@@dakine808shooter Some say the Honda strokers are the ones to beat with their large displacement capabilities. Seems like in HI you guys have a lot more Honda stuff.

[@dakine808shooter]

@@49ccscoot I'll say this about dio motos the vertical ones that's most common. For a bad design where as the intake flows across the crank , you can build a fast reliable stroker. Depends of builder of course. Minarelli just have way better bores already huge wide exhaust and transfer ports . Hard to find old skoo taiwan dio bores that come some what close to that.

[@supertedogpriken]

no lubrication holes on the piston for the exhaust bridge?? And why not?

[@49ccscoot]

I wanted to see how it did without. 3,000 miles later, it seems to work fine.

[@joshuadulaney5559]

Use plasty gauge or wax?

[@patriksmartinsmonahans6601]

15:40 Whats the diameter of the outer exhaust end and outer Flange end?

[@bradleyyounger8499]

Dang.. any chance you would want to build my am6 stroke? Lol. Finding it near impossible to find someone near me. I've built several scooters but they don't have the trans. I wish everything had a divorced trans like my Harley and cars.

[@49ccscoot]

I've never messed with any of the manual gearbox 2Ts either.

[@HunceyOSRS]

The base gasket wont change the piston position relative to the case clearence ?

[@49ccscoot]

It will. The difference in gaskets supplied is not great.

[@HunceyOSRS]

⁠39:25 The base gasket will change the piston position relative to the ports in the cilinder wall (or transferports). I wont change the piston position relative to the case. 😂 Great vids by the way love the indept content. ❤

[@49ccscoot]

@@HunceyOSRS You are correct. Worst part is I said it twice. LOL I should know better than that, but get wrapped up in the moment or don't really think about it and it's easy enough to slip up.

[@HunceyOSRS]

No worries, we are still all human. Its obvious you know what you are talking about. 💪🏼

[@julianjennings4638]

The sharp edges on the piston are fo scraping the bore.

[@hosac99]

is there a way i can match my case if the crank is already inside so i dont have to split the cases

[@49ccscoot]

Some people do it that way. You need to do anything you can to keep debris out of the crank and case bearings. Stuffing rags in there and using masking tape to shield the area are a couple of ideas. Even then, it would be a good idea to flush the cases thoroughly with kerosene or gasoline after.

[@Jeekinz]

No!

[@robertponsford8493]

Looks to me like you should of been issued a b piston as the clearance should be 0.05 mm

[@49ccscoot]

I just ordered a "replacement piston", expecting an A to measure. To meet their published spec, I'd need to go straight to C. 0.07mm is my smallest clearance.

[@robertponsford8493]

@@49ccscoot good that your going to get that clearance corrected as they do over hone sometimes and skip the re measure so if it’s a c you need then it’s a c you should run 👍🏻

[@49ccscoot]

@@robertponsford8493 I'm putting the A in there. I don't want to pay out a bunch of money or have a long wait for it. Others seem to think this is normal for Malossi and the spec is off. Unfortunately, there just aren't many people to ask because most don't bother with measurements. I was even looking at one scooter parts site that just recommends A for x miles and then switch to B at x miles. To me, you'd always decide that based on measurements vs miles or hours. Miles/hours would be inspection intervals.

[@robertpierce1981]

A ledge Ed Lee

[@TEAMVISKAT81]

the reason it does not fit is because the malossi rc-one is cast in china. it is written in very small print. by the transmissin cover. cast in china ... then it will be shipped to italy. malossi check it out. and send it around to their malossi dealer. that is why malossi is the cheapest in the class... if you want the best, then choose polini p.r.e 100cc. but then you need to find a piaggio zip sp1 or sp2 good luck with that in the usa :(

[@nazzytpr]

Sarai italiano, non ho mai sentito fossero fusi in Cina, è vero? Non ne vedrei il senso dato che il costo per le fusioni varia di poco e hanno numerose fonderie che lavorano per loro per i cilindri

[@TEAMVISKAT81]

@@nazzytpr it's true, i even have a malossi rc-one engine on my nrg mc2.

[@guidosamson682]

I would like to send you the videos of the scoots racing here in Surinsme

[@49ccscoot]

Have you got a KZbin link? Just post it here.

[@bravo1412]

nice video! but ther 1 or 2 things made thats not perfekt. one thing is the piston clearene in the case! 35:48 best is 0 but for 40-50mm stroke 0.4- 0.5mm is perfect for savtesy 0.6-0.7mm. Why ??: you want the case volume tdc als big als posible. but you want your bdc volumen als small als posible. Crankcase absolut pressur! a higher absolut pressur is better for the flow in the cylinder do to exhaustgas back pressur. the other thing is 38:40 that not matching is what you wont the the 1mm piston is for tourbulrnce, so the gas is rolling over the piston and the gas is colling it better.

[@49ccscoot]

The case volume difference that came form the small amount of clearance for the piston doesn't worry me. There are people using enormous spacers for different reeds and huge carbs that create so much more volume than me and seem to be running well. Plus, I've ran trenched cases for years that so many people say is bad, but they seem to be working. If there's a plus to volume, my understanding is that greater volume can give an exhaust more to draw from. I have a feeling that with what change I made here, no dyno would show the difference between clearanced and not. Most likely the margin for error from run to run is larger. Regarding the transfers; I've always been told level or flush is good for flow and allows for good cooling. I see what you're saying though. Some of this stuff just isn't intuitive.

[@bravo1412]

@@49ccscoot it is a same that my englich is so pore and i need hours to explain you the real thing. but i love your videos! you dide so a good job tellinmg peoble. but i need a lot of time to translate it right. google translate ist fuckt up. all thinks hast to been in rersonate. most think the exhaust must rasonate to the cylinder! and year thats right but thats only one gas change. a 2 stoke hast more than 1 gas changes. what you wont is the perfect balance between area and gasflow. and that starts by the inlet in your air filter ( the filter if big ist out) than the way to the carb. the carb it self, than the inlet, than the reeds, than case volume, the case flow it self, than case flow in the cylinder, and after all that the flow in the axhoust and the shockwave back. you have to think this way, what does gas do in that time at this speed!!! what you thing and most people do is thinking gas is like a liquid!! perfect flow all eages are perfekt. but no thatsa not how it works speazali at high speed/ rpms . ther are areas you wont laminar flow and ther are aereas you wont toutbulence flow. sorry for thats fuckt up english!!!!!

[@49ccscoot]

@@bravo1412 I can only speak English and enough Spanish to find a bathroom, so you're doing better than me. I spoke to a trusted friend that has been a 2T racer, engine builder, aircraft mechanic and general enthusiast his entire life. He follows people like Jan Thiel, Frits Overmars, Wayne Wright and others that have devoted their lives to two-strokes. He says the same as I did about the transfers and directly quoted Jan Thiel as saying that the piston should be flush or level with transfer floors to allow incoming mixture to attach itself to the piston dome for better cooling than flow disrupted by a mismatch will allow. He also says, With a well designed cylinder with good transfer and exhaust ducting, a fat pipe and lots of case volume WILL make the best power over any other build out there. I mean no offense, but I'm clearly not going totally in the wrong direction if those folks are saying this stuff.

[@bravo1412]

@@49ccscoot He says the same as I did about the transfers and directly quoted Jan Thiel as saying that the piston should be flush or level with transfer floors to allow incoming mixture to attach itself to the piston dome for better cooling than flow disrupted by a mismatch will allow. thats since from the 1980-1995! the evolution on the 2 stoke in the moto gp for 125cc. goes to the early 200x years. THE rsa 125cc engine was and still is the most powerfull desing for 2 stike in the rannge 70 to 200cc!!! 125cc 45hp for display but i know the designer the dynoed the hand build racing engins with 53-55hp on the wheel!! and He also says, With a well designed cylinder with good transfer and exhaust ducting, a fat pipe and lots of case volume WILL make the best power over any other build out there. and no!! Yamaha dide that in the 1970s! they build bigger cases every year and made more power! but ther was a volume of the case who the power goes down even wit fat sucking pips. if your care resonats bei 10000 rpm with the carb good you get a lot auf feuel mix but they cylinder resonats higher! so always you need all in resonace1!!!

[@IosuamacaMhadaidh]

I need new forks. Anyone here have any success with say Honda scooter forks on a Chinese scoot? Or NCY forks? I'm working with the Tao ATM-50-1 style and would like an upgrade from OEM

[@49ccscoot]

Are you trying to swap out the entire tree or just the shocks? If it's the shocks only, I've seen some people that seem to be pretty happy with sorta no-name stuff sold on AliExpress too. Some of those sellers post quite a few measurements so you can try to match them up.

[@IosuamacaMhadaidh]

@@49ccscoot just the shocks for now, I'll check out Ali Ex, thanks for responding!

[@czerf1]

22:17 why not do the water port? better cooling is better right?.. realy strange to me that you didnt do the cooling port. i have a aerox 70CC and i added a 2de radiator to the existing system and the extra cooling did made the drive feel better. and you can push your setup in other configurations, like i did (higher RPM for example) would like to hear your opinion in the comments or next video. EDIT: after watching the video for the 2de time at 22:17 you are talking about meat of the cilinder and i can understand that. and the water cooling is not that high of a pressure right? ( dont know, never thought about how high that gets) but cant you atleast make them meet better then they are out of the box?

[@49ccscoot]

If you look into the port, you can see that where the base meets up is actually way larger than the tiny passages for coolant to flow elsewhere. I don't see it as a restriction. It wouldn't hurt to smooth it out, but there's no real reason to match it that I see. And yes, I preferred to leave that material for case strength vs matching that I'm not sure accomplishes much.

[@BrainHurricanes]

FYI better cooling is not allways better. You want a good working temp so all tolerances are close to perfect. Too cold and tolerances are too large, resulting in lower performance.

[@PietroFerrara-ql7ik]

Trazione itali

[@danburque7555]

All stock banshee are weak and slow. If you think putting pipes on them makes them fast they don't. The porting, head work and airbox mod is the RPM killer with banshees. Deliberately de-tuned to be sold in the USA. Guys like me know exactly what to do about this. Eat my dust.

[@claudeperron780]

too much overthinking.

[@49ccscoot]

I remember most of the books I've read or experts that I've listened to say the best way to build an engine is to slap it together however it comes. Assumptions are every bit as good as measurements. Top builders and tuners generally prefer to work in dark rooms with severe time constraints whenever possible to limit time to think or the ability to spot potential issues. It's like when you watch a race and see the crew chief is out to lunch because there's just no sense in fretting over the details.

[@claudeperron780]

@@49ccscoot Yeah, smart ass answer but, the day you will have a dyno handy, you will loose a lot of your illusions. ;-)

[@49ccscoot]

@@claudeperron780 I'm not saying that I really think I'm making much power here vs others, but I've seen these thrown together without ever touching the cases, leaving a full 3mm mismatch by multiple people. I just can't do it. I generally try to be nice/courteous, but if you ever post a lot of KZbin vids, you'll see that there are a lot of haters. I read negative remarks daily that range from totally incorrect to just plain mean. Sometimes I get enough of it. My apologies. I'm just trying to share my experiences, and I actually like doing checks and stuff like that in the assembly process sometimes. What can I say? I'm a nerd.

[@claudeperron780]

@@49ccscoot It's all good. I really enjoy your videos, the TPR ones were pretty nice and it will be my next setup. Thx for the good work!!

[@49ccscoot]

@@claudeperron780 I still enjoy the TPR. It's very hard to beat for the money. Lots of fun.

[@kevinstamp1776]

Why do people think rough surfaces itemizes fuel? I'll never get where that came from . Maybe a little if a carb was boosted . Turbo a little but the carbon build up for nothing. Might as well at least let the air pass a little easier. Rough surfaces have no fuel itemization improvements at all port match it and smooth as u want to go .

[@elizabethmcheffey8699]

This shit is the best 🛵🔥💨

[@japup1237]

As usual you make a great vid everything idiot proof I have a question how did you take a couple of foul off the crank set up bearings🛵😎👀👍

[@49ccscoot]

I used a grinder with sanding stuff. Flap wheel or drum sander for the ID and disc OD. If held with the right tension, I was able to let the bearings still spin, but not fast, so it was easier to remove material more evenly.