2-Stroke Racing Go Kart Expansion Pipe Shootout!

In this video we finally get to have some fun hooping our racing go kart. We were given a set of miscellaneous expansion pipes with the purchase of this kt100 kart so we figured that we would put them to good use and make a video out of how they changed the performance.
We were able to narrow it down to a couple of choices and found that there were 2 different types of pipe. One for low end power band and one for a more aggressive driving, higher end power band. Either way both types are great and it really just depends on how you would like to drive or what track you are one.
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Gas Tank used in this video
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[@cubanob247]

Karting Enthusiast here🤙🏻. I would say if you cant go to a track just do a point to point 👍🏻. There are endless aspects of Karting to learn about but its awesome you guys are getting into it and teaching yourselves. Look forward to seeing ur progress!

[@nashguy207]

Great video guys. When racing 2 stroke go karts the different pipes are for different style tracks basically as mentioned in one comment becareful with high rpm's on long pulls you can stick the piston. Enjoyed watching the video. Hope you have a great week. God Bless!!!

[@conner1938]

Now I have to admit I’m not a big fan of 2 strokes and i never mess with them but the fact that you guys are doing something different besides a 4 stroke is awesome keep it up

[@pkuudsk9927]

ok so you kids are learning, now you can't just slap a different pipe on without re jetting the carb . To get the maximum power you need to consider temps of daily air and exhaust. Keep records so you can tune for the day and pipe . If you were to go to a real race track you would tune for a short or long track , a track with alot of slow corners or fast ones. Keep having fun while learning .

[@lukashamrin5689]

P Kuudsk its a diaphragm carb, there are no jets

[@Customwinder1]

Good stuff fellas. Bit of R and D is cool. The two strokes sre awesome. 👍

[@34bartm]

That looks like it was a lot fun. Great video.

[@colindavis2322]

Love the videos keep up the good work

[@JohnWheels]

Awesome! Love the 2-stroke. I didn’t know that exhaust could make such a difference in a 2-stroke. If it were a 4-stroke, you would just straight pipe it.

[@logiebearlrm]

I need to get caught up 😂 y’all are hilarious

[@danhambrick6331]

Two stroke madness!!!!!

[@ProfessorIgor]

within 1 second of seeing the pipes you had to choose from, I knew the winner. It is the one you picked. The Hartman Blimp with the small can-over. This was THE pipe to have for the KT100 and most any other 100cc engine from the late 70's, through the 80's and even today. The only real issue with this is that many track, including my home track of Badger Raceway had sound limits. This pipe was LOUD , but worked everywhere in the rev range. We would play with the flex-pipe length depending on the track. Longer for torque, shorter for hi-speed. This is literally the sound of my youth. Now.. Set your damn clutch up to 9500rpm, get some good fuel in it and just run a foam sock filter. You're WAY too lean up top. You're gonna stick it.

[@1MACVSOG1]

I'm just got a kt100 kart and I'm getting ready to start it up are there any tips you could give me on not fucking it up and running to lean like they are I need to let it warm up for 10 mins? And how to set hi low ideal??? 4074483959 thxs

[@garypeterson9083]

The length of pipe before it is crucial too. Try different lengths to fine tune the power band.

[@thedud3]

Nice video👍💯

[@sdgames6598]

aye keep up the vids man i just got a go kart! :)

[@bighomieJ5X]

Keep up the good work guys, did u do a comoression test yet to see the life of the engine. Generally 2 strokes eat rings with age , but a top end rebuild kit is easier than making a hot pocket w/ a 1100w microwave.. 😂🤣

[@Mad-Duk_Machine_Werkes]

Up in the front of the pipe where the springs are, you can change the length of that short header that the expansion chamber goes on and alter the powerband as well, the main reason to change pipes has a LOT to do with gearing and sprocket changes, and also when you adjust the weights in the lock-up clutch, each different setup requires a different pipe and header-

[@MOTOCKOT]

8:37 love that sound

[@crystalperez3026]

Nice video next time make them longer!!!👍🏻😆

[@jacksonsinflatablechannel]

cool video

[@Leek2x]

Lol like the race track

[@aleceshowe]

Very entertaining videos. Don't worry about the octane too much. If your ignition timing is fixed then boosting the octane is pointless.

[@lexRTD.]

Cool video. Add in one of the go cars a big wing (wang gang)

[@4793bigdaddy]

B1 is a low end pipe, the second pipe looks like a classic Blimpie pipe. The higher the number the higher the power band in relation to rpm's. G4 or L4 would be a high end pipe etc.

[@benitoguiterrez4651]

Cool

[@samurboi8007]

Did i ever tell you guys that you have a cool intro

[@robormiston2841]

I have the same kart. Emmick kart with the Yamaha KT 100 motor. Mine is a mid 1980's it will go 86 at 14,000 rpm. You can change the power band by shortening the header pipe too. I have the same steering cowl and electronics. I will look next time to see if it has an M in the seat. But I think it does. If had a few big racers want to buy my race pipe.

[@djkidd3814]

Just an fyi guys your grearing will also help ,for the area your playing in a mid tooth gear/sprocket will help but keep an eye your tack

[@michaelteeple8704]

The cone shape should send a stronger shorter pulse as oposed to a longer weaker pulse. Its the same thing you can do with port shapes and like you said top end power or low end power,what you want more.

[@michaelvangundy226]

My 2 cents. Use the leftover fuel in the weedeater. Always mix fresh and measure both the fuel and oil. Just buy premium without alcohol from the same store. Octane booster is only needed if you have shaved the head, check compression. Adding it will change the ratio and will make you leaner on top end causing ring wear. Lastly, every pipe needs different tuning to get the full potential. Have fun making a lot of laps, test and tune.

[@mikeroberts7775]

The expansion chambers move the power band around for racing on tight or open tracks. 4 strokes do not have linear torque curves in the racing world. Drag cars have a much different torque curve compared to a show room Honda Civic. Make sure you keep an eye on those long pulls on straights you may stick it.

[@blakemahowald3269]

Mike Roberts Obviously power is never perfectly linear. When compared to a 2 stroke, however, a 4 stroke has much less of an exaggerated power band. That was the point of the diagram.

[@EdWolfram]

She is running much cleaner was it the fuel or did you spend some time dialing the carb in?

[@gagerollins5810]

I have the same exact go kart. They were 1600 dollars in 1998 and it's a "margay kt100 Yamaha kart" is what it said in the sales paper

[@hunterpotter8609]

I love your videos by Hunter😎😎😎😎😎😎😁😁😁😁🎅🎅🎅🎅

[@weedsmith9317]

The gas can just stick in the tank, catch that nub on the cap stem no mess it's actually easier lol

[@MrTheHillfolk]

weedsmith 93 And then you slip and dent the fender on your car. No thanks I’ll keep the old nozzles.

[@lanetanzey5031]

U should use the dominator oil instead of the interceptor works way better imo from experience

[@aiouoctachu7273]

Pô xe nghe hay 👍

[@dirty1511]

what kind of header are yall usin

[@mickeynismocat]

Hey there, what mixture were you running?

[@elijahcormier5239]

2 stokes need back pressure, I believe that the exhaust you put on was creating more back pressure which may have added more power all around.

[@lachlanvandermeer1971]

Don’t run a paper filter! Get a fine mesh filter 👍 these engines need good fuel flow. Personally I run no filter as I pre filter my fuel and clean the filter inside the carby after every run

[@GumpterCrayon]

hey i recently bought a shifter kart with a 1997 RM80 6 speed and you seem pretty knowledgable. what are your main tips on keeping a healthy engine!

[@dylantavcar4869]

Thank god for the notifications !

[@mikeroberts7775]

All they do is change the power band around for different sizes or types of tracks. Slow tight tracks require a different pipe to fast open tracks. As for your comment on 4 strokes having a linear power band they don’t. Just think of the difference between the power band or torque curve of a drag car and a show room Honda Civic. And watch the temp on those long straights you are pulling you may stick it.

[@davidmurphy7081]

i have a problem but when my kt100 was running I took off the spark plug cover and got a massive shock but in the last video you did the same thing and didnt get elctrociuted. any ideas as to why this is happeneing?

[@AJs-Projects]

David Murphy same here. I only ever covered up the air filter or let it cut out on its own after that.

[@Mark-jw2vz]

if your talking about the spark plug boot (the rubber piece) while its running it will shock you. Thats normal lol

[@mottorcycle2559]

David Murphy don’t touch the engine, that grounds through you. Just grab the rubber boot and twist a little while you pull

[@bmxscape]

u were grounded. no ground, no electrocution

[@colindavis2322]

Never clicked so fast

[@BuildBreakRepeat]

Colin Davis Haha, thanks....this one is pretty good.

[@bdogg1010]

Please please please tell me what type of go-kart that is looked up 2 stroke go-kart and couldn't find anything..

[@lukashamrin5689]

bdogg1010 random chassie with Yamaha kt100 engine

[@SolarWolfRoblox]

hey i have a budget of 500 and i found a 196cc drift kart for 350 is that a good investment everything seems to work on it?

[@langlang1909]

SoLaR wolf yes

[@yellowbendyman8275]

Why don't you do timed laps?

[@DeliciousDeBlair]

It is still amazing that they only asked you 400$ for that thing! >0.0

[@ShiftYoutube]

The shorter the exhaust flex the better top speed and the longer the flex the better the bottom end speed

[@jlucasound]

BTW. It's called an "Expansion Chamber". ;-) At least that is what we called them in the '70's.

[@okxden]

Whats the intro song

[@dexter2433]

if you really want to make that 2 stroke sing use leaded race gas 110 oct ....2 strokes love leaded fuel ran my YZ 125 with the big bore kit 50/50 pump 93 and 110 leaded race gas and it is still easy to find in Texas I get mine out in crescent there is a gas station at the race track entrance/exit that allows the race cars to fill up the non street legal cars without having to take on public roads so you can buy all you want at the pump at half the price as the VP gas in cans.....the lead will ad a bit of ring and cylinder lube but you should do a top end on that 2 stroke about every 20 hrs (thats a full race motor ) of run time ...sounds crazy but it cheap and easy to do compared to a 4 stroke

[@nasanction]

You still haven't fixed the clutch?

[@xneqitx240]

Late gang

[@nooka6621]

Them 2-strokes can be dangerous because they can lock at times so just watch

[@lucamerauta1974]

You know that when you let go the throttle the engine is no more lubricating....

[@edgarslacis7842]

No you are not true

[@rushking19]

So what you supposed to do never let off lol?

[@kraigthirty4991]

get a no spill gas tank they are nice

[@dan_3843]

First like

[@jamesroberts4655]

Does anyone know this exact kart name??

[@lukashamrin5689]

James Roberts i dont know the chassie but its a Yamaha kt100 engine, about 17hp

[@DylanDenHaeseRacing]

That engine doesnt have apowerband

[@built2last31]

they are TUNED pipes

[@quarter_jap7270]

3 min late ❤️😥

[@bayl1065]

2 years late❤😥

[@DylanDenHaeseRacing]

That isnt supposed to idle it burns out the clutch

[@colindavis2322]

5th

[@edgarslacis7842]

Guys i think it has a 2 stroke

[@paulbxiv]

Motor cc? ?

[@smartin1732]

100cc. Kt100 Yamaha

[@crest2471]

3rd comment 4th view 4th like

[@elijahcormier5239]

122nd comment 42,426th view 639th like

[@fc3sboy1]

That poor motor. Yall are runnnin that full on lean. You can hear the point in the exhaust note where it leans out too. Its too rich off idle and goes flat lean high rpm. All pipes you can hear it. Richen the main jet a few till the motor cleans up high and adjust the idle mix and needle hieght

[@AJs-Projects]

Randy Slagle what do you mean “main jet”? There’s only a high and a low jet.

[@fc3sboy1]

Car Central Media there is a round slide carb on that motor. The main jet is what the needle slides into

[@dayyou]

It would be all the fuel booster they put in diluting the fuel oil mixture.

[@lukashamrin5689]

Randy Slagle no its a walbro carb, a diaphragm carburetor

[@bigcazza5260]

kts are generally smokey as shit at lower rpms, and they generally dont smoke when revving

[@DylanDenHaeseRacing]

Why is that thing so lean holy shit

[@bjakers6473]

Change pipe change the jets poor cart won't last long I'd love to buy it...

[@way2dumb]

THAT STUFF YOU SAY ABOUT THE POWER CURVE OF 2 STROKE MOTORS IS TOTALLY WRONG. bloody hate caps lock

[@avrahambrea1919]

Sounds a bit lean

[@AJs-Projects]

Budget Friendly RC how can you tell?

[@avrahambrea1919]

Car Central Media just listen to it

[@karl6823]

Budget friendly r.c , I totally agree it's running Lean she's screaming to hard. Two stokes oil runs through my veins, when you get air cooled two stroke dialed in she we hum with a tone like no other

[@timhancock64]

Adjust the hi end needle your gonna ruin that motor

[@davidsferrazzo]

I’m not a big fan of the opening song for the intro, the intro is good but the song kinda sucks

[@ryanclayton8818]

Its a shifter cart dude drift that shit spin it and 360 it

[@filipecunhadias5309]

God, bad clutch and bad tuning, that engine can run at much much higher RPM

[@lukashamrin5689]

Filipe Cunha Dias true, I raced these 2 years ago and my ears were bleeding when driving it lol

[@bigcazza5260]

no point going past 15 grand

[@lukashamrin5689]

Big Cazza what do you mean

[@bigcazza5260]

also look at his rear sprocket, looked like low 80s, we usually leave 86 on the rear and go between a 9 and a 10 on the front

[@lukashamrin5689]

Big Cazza i didnt change front ones, i was usually using a 78 rear

[@Wylie013]

Stop bumming around on deserted streets and take it to a real race track, also if you change the length of the insert between the header and the pipe it will alter the power from bottom end to top end

[@johnvessey1339]

Please educate yourself on two stroke motors,how expansion chambers work and carburetor jetting,your making me cringe

[@ichbineinebiene6234]

Do your homework first, before talking about things you clearly don't understand!!

[@blakemahowald3269]

ich bin eine Biene Care to elaborate?