Two Stroke Cylinder Porting Tips | WATCH THIS BEFORE YOU START CUTTING! 2 Stroke Tuning

Tips on how to port a two stroke cylinder, what to do/not do and how to do it right.
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[@ahbalone]

Always go for MAX porting on your paper weight.

[@MrTheHillfolk]

2:00 good tip on the glue. I had to surface an oil pump cover for one of those Chinese diesel clones as it was scored. I couldn’t hold my finger on it as it was about 1” or 25mm in diameter. So I used crazy glue to glue a short stick on it, and it worked like a charm on the lapping plate. Love those tips.

[@zomaardan]

Im really sad today. So i watch my favorite oploader old vids to cheer me up.

[@darrencolegold3642]

A good tip for using carbide burrs on aluminum is to keep them lubricated, a spray of RTD spray from time to time will keep the cutting tool clean and sharp, which makes for a consistent and predictable tool.

[@whirlybirdrc]

Three years later and this tip is as helpful as ever.. thanks!

[@wendellfugate9069]

Many thanks for your help. Truly appreciate. The higher velocity intake and exhaust in smaller diameter may just crispen-u my 7cc's throttle response and power.

[@AuMechanic]

Good tip with the ring boundary. Got a few porting tips for anyone starting out, maybe cover in a video some time. But 2 basics tips for anyone just starting out is 1 do your porting changes to the Exhaust only to begin with, transfers require a careful hand and eye and a mistake can send the power off a cliff. Exhaust timing is fairly straight forward and a small errors wont kill it. 2 is make the port height change on piston first, removing material from the crown so the edge of the piston only where the port is located is lowered to effect the new Ex port timing, Once that has been tested, copy that to the Exhaust port and fit a new piston. Pistons are cheaper than Cylinders so if you make a mistake by going too far it only cost you a piston and you can do the job again on another one without going too low and then run it and make sure that's getting the power curve you wanted and if all is good then transfer the same timing specs to the Ex port by porting it and fit a new piston.

[@2STROKESTUFFING]

+AuMechanic Great tips, thanks!

[@EarthSurferUSA]

I port small 2-stroke cylinders, ex, in, trans, (my living), with a Tormach CNC mill and finish them by hand. I now hate the "hand" part.

[@ezgaming8101]

How can I make my moped rev higher I have installed a 70cc kit and a bigger carb and can only get 50mph

[@davonmulder5272]

@@ezgaming8101 that's actually pretty good for a 70cc, what bike?

[@ezgaming8101]

@@davonmulder5272 it's an ajs firefox u can't buy any thing for them u have to get every thing form manufacturer it has a technigas exhaust on it from a vespa too

[@eduardodiaz5762]

Informative and I like that ending/intro music... Makes me feel like I'm in Fallout NV

[@jarikinnunen1718]

Someone found accitentally pipe-cylinder resonances in sixties. It is ruler of power.

[@hafiz20115057]

Thank you .your tips really help me much

[@noshirirani6685]

Yes i second that, port chamfer is important .

[@gibbyrockerhunter]

Greetings from the Blue Mountains U.S. long time watcher, first time comenter... I think. im about to do some work on an old chainsaw and wanted to get in the zone. I poured some vodka(out of rum), put on my flat brim cap from the local speed shop, and tuned to 2STROKE STUFFING. almost to the spot. I cant wait to see your new cast cylinder. I know it will be a while but the more videos along the way the better. thanks for your dedication to the art. ciao

[@BillyRillkratz]

Always great ideas! Cheers

[@RANKITRANKI]

I love your channel , grettings from Spain ,

[@2STROKESTUFFING]

+RANKITRANKI Thanks!

[@frankcrawford416]

Man some real porting tips. Thank you!

[@rayatech9721]

Jawa barat hadir mister.... Kapan kapan main ke ciamis. Ntar di kasih makan jengkol... Hahahaha

[@frankierutherford1888]

Good job thank you for the info .

[@2STROKESTUFFING]

+Frankie Rutherford Thanks!

[@crosslukas9952]

How come i really love this mechanic videos when i barely can change a piston om my 2 stroke engine . Im dreaming of learning myself to atleast averege at this .

[@cistokrvnibosanac1266]

easy,start fucking up engines until you do it

[@FRANZOLLI144]

Alguma dica básica para o cilindro da ktm 50 ano 2015???

[@zagrepcanin82]

great advices for me....i have a ruined cylinder of morini ac....my crank was out of balance....so i will hone it for o1st or 2nd oversided piston and do the port thing too...

[@LMCtubokuChannel]

Nice working....good job mike

[@Robodriller]

I like my port timing right at 210° exhaust, 135 on transfers and raised the boost port a bit more

[@2STROKESTUFFING]

+Nick Mieloszyk Try lowering the transfers to 130-132, you might be surprised... Only works with very good transfer geometry.

[@dustinmoore4336]

I learned alot of tricks close to what he shows from my dad we built a 2002 banshee together back in 2011 and stock there about 34 hp. After porting, the cylinders, slightly modifying the piston. The stock bore and stroke It ran about 38 on the dyno, and the change it made for when I hit the powerband was amazing It was like spraying nitrous to it while it hit the powerband. The only negative was it ran hot alot, and about 10 hours you were putting rings in it because of the heat

[@zakn3954]

Sounds Lean

[@lifeononeweel3008]

Only 34hp wtf its a two cylinder two stroke it should have alot more right?

[@BasVossen]

nice one! ps they call it 'can of worms'. Many old timer Tomos 4L and Puch cylinders have been upgraded by me, after I destroyed a bunch to learn. I didn't decrease the compression timing, just worked inlet (Venturi) and transfers. Sometimes I made extra ports and cut little holes in the piston that connected with them. Best of luck with your porting projects!

[@lilman1796]

Great info ,thank you, keep up the great work ☆☆☆☆☆ .

[@gwo7610]

your braver than me.. those iame 39cc motors are super expensive, everyone in the british mini bike championship has them, very quick

[@wornknobby]

Very good video. Helpful and informative. Thank you. Can you do a piece on air cooled two strokes,especially big bores?

[@christopherknee5756]

I heard that plated Kawasaki engine cylinders that were damaged were easily repaired by boring the cylinder out 2 mm or 3 mm (on the radius) and then pressing in a cast iron liner. I am not sure how easy it is to cut holes to match up the port holes but I sure a trick can be thought out. This could give you more chances of getting the porting right. I am not sure if cast iron can be chromed or not. I know brass can be. Brass is soft and easy to cut. It is used by RC Nitro engines for the cylinder liner.

[@hoon12345]

Also I found dipping the item in 2t oil or another oil helpful in catching the metal bits and smoothing the process

[@eduardodiaz5762]

Cutting oil would work the same would it not?

[@bobanalyssa3932]

Do you do a vid on the basics of case stuffing, thanks!

[@JalapenoBrothers]

Good Tip,cool stuff

[@2STROKESTUFFING]

+JalapenoBrothers Thanks!

[@mattywollaston3996]

Bloody awesome!!!! Thanks heaps for sharing mate, you made a hell of a lot of sense, and made me understand porting way better than before. Cheers bro 🤙🤙🤙🙏🍺😎

[@reelphatties6426]

Great video

[@emilgaming8327]

Awesome great thanks 👍

[@2STROKESTUFFING]

Thanks!

[@CaptainCurt07]

You sound knowledgeable! I’d love to see a diagram to better understand n do my Husqvarna CR250

[@kevinavillain4616]

Kind of curious what you think of the two-stroke tuners handbook that you got. As a kid I got a hold of a copy of it when it first came out. By the mid-eighties I was discovering there were things that could be changed in the calculations to increase the power band width at only a slight cost to peak horsepower. These were in however relatively low RPM engines >10,000 compared to the insanity of your hyper tuning. Kudos. This old fart is he enjoying learning some of the new stuff going on as I kind of dropped out of things for the past 25 years.

[@colta51]

Good tips!

[@2STROKESTUFFING]

+Sean Fiba Thanks!

[@gislemark79]

More of this. Show us yor tools for porting.

[@2STROKESTUFFING]

+gislemark79 Coming! I'm going to take you along as I port the Spx cylinder.

[@gislemark79]

Nice. But i don't even have a garage :(

[@chapogarcia3421]

@@gislemark79 same :( my moms living room is trashed lol

[@snafuequals]

I have a spare bedroom I used to use as an office. There are motorcycle parts all over my desk and pretty much every other surface now lol

[@Y2daT420]

i use a dremel with the flex cable attachment . for bits if hogging i use carbide toothed cutting bits. then sand paper barrels for smoothing and polishing.. **trick for polishing aluminum with sandpaper barrel . is to immediately apply heavy enough pressure to slow the dremel significantly. this slows the cutting action while creating heat that smoothes the surface,, ** wire brush attachments are good polish starters also. then i move to buffer attachments with buffing or valve lapping compound to achieve a mirror like finish.

[@rotazracing4635]

Hey great channel, I like your your content. When doing the radius on the port openings on the inside of the bore of the cylinder, I bend some chainsaw files to different angles and file from the inside of the cylinder to port opening. Takes longer but less chance of flaking the Nikasil.

[@2STROKESTUFFING]

+Rotaz Racing Thanks! That's a great tip and I've actually used the bent file method alot myself. It's safe, and sloooow..

[@SiboenChanel]

thank you for sharing very useful ...... in indonesian mechanic

[@perrypebriant506]

Eh ada kang siboen.. 😁 salam dari subscriber mu hehehe

[@k2rtechmanual690]

wihh kang bun jebule bisa bahasa nginggris hahah joss kang

[@muhammadmakhrufmmakhrufm9421]

ontong ketikan nak ngomong langsong paleng mueduok wkwkkw

[@diaryaz2973]

Wkwk dx sengaja nemu🤣

[@ayamtelur1337]

Oooo kang boen

[@Lord_Verminaard]

Wow, a lot of content in a short video! If I ever blow up my Stage6 cylinder I might buy a cheap-o cylinder and go at it myself just for funsies.

[@2STROKESTUFFING]

+Brendan Doyle You should, it's fun!

[@MrTheHillfolk]

2STROKE STUFFING DIY is a lot more rewarding.

[@1worldgaming18]

nice one but i'de like to see some demonstrations of this cause i don't have cylinders laying around to experiment on and port timing too , what are the calculations(and mesurements) one needs to do in order to have the right thickness of cylinder gasket(bottom) when mounting the cylinder , i use to know on my old scooter but its been 15-20 years since i did it last :) i used soldering tin of a certain thickness and put it in between the cylinder and the head and torque to spec(that i have also forgotten) then i turned the crank a full rotation and mesured the tin thickness afterwards 0.9mm was the target on that specifik cylinderkit on that engine , but it must vary from engine to engine and from cylinderkit to cylinder kit have a good one

[@raduandreidavidescu1833]

good info

[@TYGAMatt]

Good tip on the diamond burr. Another good reason is that the Nikasil can quickly wear our a carbide burr. So you end up with useless tools and a ruined cylinder

[@sowbalansowbalan3270]

2 stroke high speed tips

[@patrickmuller5223]

Helo this is a awsom video, i woud like to se more of this kind, cuz to get knowlidge is haaaard,

[@davidmorrill6740]

Thanks

[@frankcrawford416]

I have a 78 Yamaha Dt400 and have ported it. Along with other changes to the port timings I removed the sleeve separating the boost port from the intake as I redirected the boost to aim to the front (intake side) of the combustion chamber. I have heard somewhere that desert racers add a window in the intake side of the piston (above the original 2 windows) to aid in under crown cooling and add power. Can you tell me how it works and how far below the bottom ring land to cut the hole so that it does not cause any detriment?

[@warscarz5541]

I just use a bright color fine point sharpy And set the ring and mark it's easier cuz I mark transfer height and I can also mark boost port height and exhaust port as well and cut so I don't have to stop and remark

[@808pyroboom]

sup man I have a few question but I was curious would it affect power range or any stress to a wc bore. thinking of having it over size 54mm to a 55mm would it increase the power of great value?

[@matthewgilmore5307]

3 new cylinders to the trash, bike still apart and waiting on my 4th cyl. i need more schooling , and thank you for your information (the ring trick i didnt know) lots more im sure i dont know. 2 stroke and 4 stroke is night and day

[@shawndubay4050]

Sounds like it's going to be a powerful beast of an engine. Speaking of 2 strokes. I just got a brand new husqvarna lawn trimmer. It was quite a bit pricey but worth it. I was wondering what would be the best way to "break in/wear in" the new engine as everything feels pretty tight and has a lot of cylinder compression. I want to keep this machine for as long as possible and want to do the best I can to break it in correctly for a long engine life. I have not had it past half throttle yet as the power was not needed. One tank has been ran through it. Thank you in advance for any help or advice that you can give. It is very much appreciated. You do great and amazing work with engines and trust your advice highly. Have a great and blessed day.

[@cistokrvnibosanac1266]

let engine warm up for 5 mins before working,change choke position accordingly,use high quality 2 stroke oil within range :1:30-1:40(atleasr what i use) every now and then clean out the carb filter.Check for spark plug gap and compression every few months.Look if there is any leak like on carb gasket(means torn gasket or carb is curved-fix it by removing all excessive things off of it and put sand paper on glass and do circles until its fully flat. Every year check if bearings are ok and if seals are torn appart or they let mixture run out.Check your differential head if it has any play and sometimes put grease in it.

[@minnah22a]

💙💙💙🔥🔥🔥 thank a lot

[@ronalddaub3789]

it's all about physics and stuffing the holes in a crankshaft will move more air and gas mixture

[@DiabloStuntTeam]

Hi! Very good information gaid! Why u cut the sleeves on the bottom? I just broke one of them by dropping it by mistake. Can i cut them like you and test it or i must make some changes to the carter too?

[@wreckedrc5137]

Have you tried single cut carbide burs? Haven't tried myself but grind alot and My guess is that would work. Very in-depth explanation good video

[@2STROKESTUFFING]

Thanks! I used single cut burs to rough shape the Spc crankcase, works great!

[@brakhayhurst9214]

How do you come up with the port exit geometry / or where to aim the port what does what ?

[@erikeggenbakstad]

Ikke så vanskelig å gjenkjenne en nordmann her (No offence ;) ) Thumbs up and subbed!

[@donnywalker4691]

Very good I see a lot of guys hog out so much material thinking it better most of them wreck the cylinders

[@user-nq8nf1fs2i]

Hi, man. Very good job! I have an Arctic cat Cougar 440 tell me if you know if you can waste cylinder liners? If it is possible to up to what size? 70 mm? For example?. Will the cylinder wall be too thin

[@jahasmitasmitas3338]

That's funny to see finnish text on brake parts cleaner can :D

[@RegulareoldNorseBoy]

Why ? It's Biltema. Many Norwegian Comodities coemes woth Dk,SE,No and Norwegian declerations and names

[@jahasmitasmitas3338]

@@RegulareoldNorseBoy It is just funny, so why not?

[@tunturimies84]

Niimpä :DD

[@JonasSagli]

What`s your thoughts regarding matchporting? Saw that you were talking about the angle of the transchannels and stuff there.. I allways match the transfer channels to the engine block (or visa versa) but usually avoids to do any more work up the ducts, exept grinding off "cast beard" and such..

[@2STROKESTUFFING]

+Jonas Sagli I do it the same way you do. If I need more crankcase volume I grind out the ducts tho.

[@yudhithekid]

I have a 5-ports peculiar LML 150 cylinder with a pair of main transfer ports significantly smaller than a pair of auxillary transfer ports; do You have some tips to fix the ports flow in this kind of cylinder?

[@timokenful]

We need a new video, with the extra experiance you got❤️🙌

[@ericellquist7007]

I hope that you can answer this for me, you seem to know what you're talking about and I genuinely want to know. Back in the day, some builders of British custom bikes would reverse the head on the Triumph 650 twins so that the exhaust was at the rear and the carburettors were up front. I believe that the cam timing had to be changed as well, although I'm not sure of the details; I have seen pictures of bikes with this mod. With a couple of velocity stacks attached, this acted as a sort of "ram air" setup at speed. What I wonder is this, can this be done on a bicycle two stroke kit, can one reverse the piston and the cylinder and have the same effect?

[@ebeneZr]

Eric Ellquist that would be a interesting video

[@11sjv]

if u start it backwards it runs backwards

[@sverrehoumb]

I know this mod have been used at old pre-unit Triumph, but then with a blower/compressor. Not sure If it would actually give any measurable effect by just turning the head. One of the old flat track racers buildt by Von Dutch back in the day had this. Pictures exist. Cheers!

[@acurarl9929]

Can you do a video on ports. An blow down an such an how the ports wrk exactly an when an how an wat. I’m fairly knowledgeable an when you said a wider exhaust is as good or better then a raised one got me interested an asking more questions to myself then I have answers. Also you said if I raise cylinder then I need to raise exhaust port. Why? An blow down is very important ? Why how. I’m interested very much I guess I just didn’t quite understand all I should. I have a 4cyl 2sttoke merc/force 120hp jet boat engine I’m tearing down to bore an rebuild. I’d like to do all the tricks I can like port it out. Just need more info I guess. Also the engine is all aluminum an the intake is as well an it’s cast but very smooth I was under impression that it should all be rough in there. Maybe you can touch on that as well. I think everyone would benefit an would love a port/porting video an the timing an blow down an wat it all means an how it all wrks. Thx love your wrk. Ps I know your busy but if an when you find time. Again great wrk

[@hosac99]

hey i purchased sleeve for my cr 250, and installed it and ports mismatch slightly on some edges bike runs great, should i match ports exhaust and transfers for increase in power?

[@goodfellasinc.5648]

Good video's

[@2STROKESTUFFING]

Thanks!

[@meskalin64]

When i was 15 and had a moped i did everything to be max size. Some worked some didnt.

[@samwalton4598]

Just bought a 70cc kit and crank for my Yamaha 50cc minarelli horizontal engine. I was thinking of just polishing the exhaust port side for better flow. I don’t intend to remove much metal just smoothing what’s there for efficiency. The casting is fairly rough. I’m thinking if it’s smoother there will be less carbon deposits over time? Thoughts? Love your channel👍

[@JawzProduction]

Exhaust smooth intake rough !

[@zainudinajaxajax]

Can u explain to mee,im from malaysia and using TXR 150 panther suzuki,japanese bikes,it a fenominal here arounds early 90ty,untill now ive still using it,so can u show me how to modify,pirting bore those bloks cylinders,

[@jimccc9467]

What was the Iame cylinder for? We did a lot of go karting and raced both 80cc air cooled and water cooled 125cc. I’m curious about their involvement in scooter builds. Thank you

[@xtremelefkas]

hello, what about cylinders wih the reed valve/intake port on it ? should i port the intake, downwards (opposite of the exhaust port) ???

[@rumbleglass4437]

My bike has been running good for a few days now besides that it runs hot if idle’ing but okay when running

[@joebidden4914]

What about just smoothing the ports out? Keeping original shape and size maybe slightly larger just want to clean up the extra metal? Also would you reccomend polishing the big port coming in and the chambers? Coming from where the cylinder meets the bottom half of the motor. Sorry I'm very new to two strokes. Thanks for your awesome videos!

[@mansikkamies9146]

Only polish exhaust not intake

[@wendellfugate9069]

*crispen-u. Sorry about the typos. My phone's screen has many black marks obscuring the letters and numerals, etc. Need a 1 iece intake to bolt my VM22 Mikuni directly to the Rest block. The 30mm intake and 28mm Oko in it now is blubbering and powerless.

[@julianlaustsen1991]

tar du på deg porteoppdrag av motorsager eller crossere?

[@biff1tannen]

My Suzuki ts50x from 96 will get a new 50 mm mallossi sylinder and porting next vinter🤩

[@BoostedVr5]

Can you use also alone the stone burs in the edges in the port without distroying the nikasil couting? 🤔

[@patrycklealoliveira8106]

Friend, good morning! From Brazil. I have a big problem with a Chinese Thorq 62cc chainsaw. I tried to start it and when I pulled the starter cord it was very hard. I removed the spark plug and it turned the engine free when I pulled the string, but if I put my finger in the hole where the spark plug goes, the piston is completely locked as if it were vacuum or excess compression. Do you have any idea what it could be? I disassembled it and the connecting rod, crankshaft and bearing, piston rings are good. The piston had carbonization on the top but I cleaned it and also decarbonized the cylinder. I can't find the new cylinder and piston for it, as they are 48mm in diameter. I only found 43mm and 45mm for sale. When I assembled it, I still had the same problem, as if it were a hydraulic wedge, an excess of compression that doesn't allow the piston to descend or ascend freely. Can you give me any tips on what is causing the problem?

[@breezetixmoto]

What was that tool you were using called in the thumbnail?

[@rustykrys888]

Omg u made me laugh at 5:10 with that comment 😂

[@intellectualgamers]

I saw in the last video your cylinder was scored. I have a similar scoring on my cr125 from a piston failure and just wanted to ask i you have ever honed a nikasil cylinder. I cant find any useful information on that online. Everyone says dont do it you have to replate it but noone seems to have actually tried. Thanks

[@2STROKESTUFFING]

+Karel Kraus A quick gentle hone won't hurt. Read through the comments on this video, there's a guy explaining it there.

[@shoominati23]

A little tip of what I do for quicker ring bed-in and less propensity to seize (especially on tight cylinders) is give you cylinder a quick hone with a diamond hone (I mean like less than 30 seconds) with not much outward spring tension and using plenty of WD40 sprayed repeatedly. It will run in quicker and also it helps to smooth out any sharp edges left from the porting. Just my 0.02

[@2STROKESTUFFING]

+shoominati23 Great tip, thanks!

[@sciewter]

That makes sense after a port job. I was told to never hone a Ni cylinder but doing very minimal to take off any burrs or rough edges makes sense.

[@shoominati23]

I should reiterate. Probably 30 seconds is excessive. Just get the drill turning slowly, not even quarter of a trigger pull. Do about 5 up and down strokes with plenty of wd40 or other lubricant such as 2t oil,, then turn the cylinder around and do it the other way. Make sure you don't pull the done out of the bores too much, as you risk burring the edges of the bore. WD40 is just convenient as you can have the cylinder in the vice and spray it in with one hand and hone with the other. I was just told this trick by old old racer who tuned Yamaha Rd400s and kawasaki triples, that this was just a little trick he used on brand new tight cylinders, especially single ring pistons with high compression and tight squish as a little safeguard against soft seizes, especially when you are pushing everything hard, every little caution helps. I use this hone, I don't like the dingleball type hones, they dont last long and are often too rough, better for car engines. : www.scooter-attack.com/cylinder-hone-motoforce-universal-mf99-00804-39.html (You can get the exact same tool much cheaper on FleaBay though F.Y.I.)

[@2STROKESTUFFING]

+shoominati23 Thanks for the clarification and tip! I've been using the dingleballs but have lost the one I had and need a replacement.

[@MrTheHillfolk]

Have you tried total seals dry film lubricant for new rings/fresh cylinders ? I’ve had great luck in automotive engines with it, I’ve never had a seating problem using it.

[@pedromarreiros7256]

Hey good video? Were i buy one dremmel 90°

[@charlesbyromhammiii2594]

What motor is that jug off of? Or name if motor so I can look into purchasing one. I have the 80cc/66cc china 2 stroke kit. I want to and try the motor your working on to see which I like better.

[@rumbleglass4437]

Best video ever I hade to try it!PLEASE HELP EXPLAIN MY BIKE I bought a long stroke100cc cylinder n piston and put it in my 80cc short stroke bike I cut 3/16 off the top of Cylinder,bottom of piston,bottom transfer ports,bottom of intake ports,and top of exhaust all were cut 3/16..HOW SHOULD I OF CUT IT?

[@connorssmallengines6663]

Port timing will be way off due to massive difference in stroke, rod, and your cuts

[@waynewright5504]

The duct exit area should be 75% of the Effective Exhaust chordal area ie x the Cosine of the roof down angle.

[@jakepethick6253]

Is there a ratio how wide the exhaust port can be to piston bore

[@sabraseraph3648]

Please make a video about how to get torque from lower RPM without having loss in HP and maximun RPM .

[@rumbleglass4437]

Hi I need help! I bought a 100cc kit on eBay for my 80cc motor bicycle kit and it didn’t work because the 100cc 50mm kit from eBay is a long stroke and the piston hits the crank!So I cut 3/16th inch off the bottom of the 50mm piston so now it won’t hit the crank and so that the piston is now the same size as the lower end of 80cc piston,but the top end of 50mm piston is 3/16th inch shorter than original 80cc piston so I cut off the top of 100cc cylinder that was 1/8th inch thick to try to make up for the loose in compression because new piston is shorter on top..MY QUESTION IS after seeing you video on raising your cylinder you said to then lower all ports and raise exhaust port but my 50mm piston is 3/16th inch lower on the top end So do I still lower all my port’s and raise exhaust port? What else do I need to do to make this 100cc 50mm long stroke cylinder and piston work on a 80cc short stroke bicycle kit besides cutting off bottom of piston and cutting off top of cylinder?

[@davidjordan4240]

After cleaning up the ports and not raising nor lowering the the in and out flow timing. Do you usually need to modify the carburation and is so, would you usually go leaner or richer. I am getting a bog when quickly hitting the throttle, but increases nicely is I slowly raise the slide. This is on Artic Cat Jag snowmobile. Twin cylinder and a single carb. Thanks.

[@cistokrvnibosanac1266]

if it bogs at start but not at end or mid its air mixture screw else it has to be main jet.With these port i would run it richer but would find idle gspot with adjustments (set it where it feels fastest rpm)

[@milindsathe4584]

Bro in block there is nicasil so, which material is used for making nicasil .if we make nicasil slewe and put in rx100 Yamaha block then is it successful. Plz guide me

[@ronniewilliz153]

Ive gont through 2 nitro rc engines so far with trying to mod them. 1 broke the wrost pin another wont run u less half throttle. Is it the same with nitro rc engines.

[@wilfrytoledo7233]

Hi, I would like to know what those tools are called

[@derknobit2616]

I would love to see what you could do to a cheap 66cc bicycle engine

[@2STROKESTUFFING]

+derk nobit Would be fun! When finances allow!

[@derknobit2616]

i will see what I can do to make this happen

[@2STROKESTUFFING]

+derk nobit 😀😀😀

[@derknobit2616]

Would be early next month

[@2STROKESTUFFING]

+derk nobit Awesome! No pressure tho😀

[@mattmaly2901]

Were u get the grinder thanks

[@miltonulm5102]

I a cylinder of a used bike with one exhaust port(duel port) lower/higher then the other

[@marioraja4229]

what port duration degrees are you running? (or what degrees are you recommending to have awesome power)

[@2STROKESTUFFING]

+Mario Raja I'm running 204 exhaust, 130/132 transfer. Recommended for awesome power! 😁

[@MrJolppy]

I have. A cast iron head it is scored on intake and exhaust, so how do I go about smoothing it out so I do not get the scores on my pistons for the new rebuild kit I can send you pictures if you PM me

[@Rodrigo-kc7mg]

quero muito ver seus videos,mas nao consigo entende pois eles sao ingles :(

[@EarthSurferUSA]

I don't know how much of a factor "blow down" is for performance, (other than being too short and forcing combustion down the transfers). If you raise the exhaust port, you are increasing both the exhaust port duration and the blow down phase, and will usually see an increase in higher RPM power. I would bet in most cases if you raided the transfers to have the stock blow down, (the same as the exhaust port change), you will usually see a decrease in power. I don't think it is the loss of blow down that hurts the power, (again, unless it is so short that the transfers don't flow well and mixing happens), but that the transfers just have too much duration. My opinion.

[@EarthSurferUSA]

I can't watch anymore. I just can't. Just remember, anybody can post a vid. Sorry man. I know better.

[@2STROKESTUFFING]

+EarthSurferUSA I'm sure you do...