@@littlereptilian7580 less parts to break though and no high pressure e pump as well. Never was a fan myself everything I own is air cooled and carbureted.
Awesome video, extremely well, and simple explanations! Used to run SmartCarb 2 in my last 300XC KTM, and was like magic! Couldn't explain how crisp the bike was compared to Mikuni and Keihin, no matter where I rode, doing nothing. 🙄🙄
Your diagrams are great, finally a video that allows me to understand how this carburetor works! I'm going to make some adjustments on my Keihin and why not try the SmartCarb later 😏
Listen man, THIS CHANNEL HAS THE BEST VISUAL EXPLANATIONS OUT OF ANY CHANNEL ON TH-cam! OUTSTANDING ANIMATIONS!! PLEASE KEEP THEM COMING! Do you have a PATREON page? I would love to support this channel!
Thank you so so much Tony!! 🙏❤ I really appreciate it 💪 I don't have one actually, but if you you'd like to get some merch, it would help the channel, for sure 🙌
The "scoop" as you call it serves a much more important purpose than you mention. It's purpose it to capture the dynamic pressure ("ram air" pressure) of the air entering the carb. Without it the carb would go lean at higher throttle openings. The Lectron uses a second, adjustable, jet and nozzle to deliver extra fuel at high throttle openings, the Smartcarb uses the dynamic pressure of the air's movement to pressurise the float bowl and deliver extra fuel.
Goddayumn this bro never disappoints! Leading the fore front of dirtbike engineering explanation on the world for sure! what a genius ideia this carb design is!
Great video, especially with the animated views and explanations of how the carbs function. To me, a big downside to the Smart Carb is that they recommend a complete servicing every year or two (for a cost of approx $200.00). The hassle and expense (as well as down time for shipping, etc) is a big drawback. I've never had to send in a standard carb for servicing, even with 10+ years and 350+ hours of ride time. The other negative is the installation process. Having to remove and then cut/trim the air boot is more than most people want to deal with (including myself). The Lectron carb does not require any of that for installation. Lectron also needs servicing once in a while, but I don't think as often as the Smart Carb.
Not sure where you're getting that information but SmartCarbs do not need to be sent in for servicing. We do recommend a thorough cleaning with hot, soapy water, carb cleaner, and compressed air once a year - especially if the carb has sat for some time without use. Rebuild kits containing all service parts (o-rings, gaskets, etc) are available and a rebuild is recommended every 2-3 years. That's something anyone can do with a handful of common tools. SmartCarbs have the smallest part count of any carburetor in this space and require no more maintenance or servicing than any other carburetor. What you may be thinking of is our Factory Refurbishing service which is $200. It's not typically recommended or required unless the carb is in really poor shape or is quite old. It involves a full tear-down, sonic cleaning, rebuild with all service parts replaced, and reset to any factory baseline tune specific to the bike it's to be installed into. That's a service we offer for any billet SmartCarb owner, new or used, and those choosing to use it can be sure that their SmartCarb has been thoroughly inspected and checked through by our technicians. You don't need to remove the airboot to perform the trim for proper internal venting in the SmartCarb. We recommend pivoting the subframe up and out of the way and the trim, if even required (Betas do not require it), can be made very easily in under 10 minutes. We recommend a dremel tool with a barrel sander. The trim doesn't compromise the integrity of the airboot nor does it affect the performance of any other carburetor - but it does ensure that the SmartCarb is venting properly, which is critical for top end fuel flow (SmartCarbs need no power jet like the Lectron does) and more complete air density compensation. The installation videos on our channel provide step-by-step instructions.
@@SmartCarbFuelSystems Thank you for clarifying this. I looked again at the SmartCarb website and realized that I misinterpreted the maintenance guidelines that were listed. I would still rather not have to do even a "basic servicing", considering that I've never had to do that on a stock carb, even with hundreds of hours on it. As for removing the airboot to perform the trimming, I got that from the video put out by SmartCarb, for a 2019 KTM 300XC. th-cam.com/video/qp7VNc3RhPI/w-d-xo.html All that said, I am still considering at some point trying the SmartCarb on my 2019 KTM 250XC. I recently installed the new Lectron Billetron carb, but might still try the SmartCarb one of these days to see if it performs better than the Lectron.
@@waynemodesitt3445 the maintenance guidelines we provide are merely suggestions. If you ride often and don’t let fuel sit in the carb and avoid ethanol if you can then there is minimal maintenance required. Just keep it clean and do that rebuild as needed (typically around 3 years depending on use). Your KTM would require the boot trim but again it’s very easy to do, you only do it once, and we are available to answer any questions you may have. Our Quick Start Guide, included with every purchase, provides a visual way to confirm proper trimming. Regarding the SmartCarb vs Billetron you might check out this recent video comparing the two on a Sherco 300 SE: th-cam.com/video/rPEBhnSyxbo/w-d-xo.html
@@SmartCarbFuelSystems I watched that video a few days ago (comparing the SmartCarb vs Billetron). I was having similar issues with the Billetron (leaking seals, plus several adjustments leaner on the metering rod, and I'm still getting some oil out the back of the silencer). That video is what made me consider trying out the SmartCarb, especially if it really does perform better than the Billetron, particularly at low rpm (I ride a lot of tight/technical singletrack). How does one go about avoiding ethanol here in California? Other than buying race gas, I don't see a way around it. I do drain the carb if my bike is going to sit for more than a week or two.
@@waynemodesitt3445 Hard to avoid ethanol in CA no doubt. If you can't avoid it then we simply recommend that you ride frequently and cycle new fuel through the fuel system. Don't let it sit for too long. If you store the bike long-term then either using a stabilizer or draining the carb are recommended, though we tend to want to leave fuel in it to prolong the life of the o-rings.
Per SmartCarbs recommendations; when transporting or if you lay the bike over for more than a few seconds, turn off the fuel petcock to avoid the possibility of fuel running into the crankcase via the fuel nozzle/slide. This is no big deal and should be done on a traditional carb as well or else it will piss fuel out the overflow vents. I just ordered a SC2 for my 18 TE 250, and am looking forward to getting to know it. 👍🏻
@@TubolMotoadventures I just did a fresh top end and mounted the SC2. I’ve only got about 30-40 minutes on it so far and as expected it is a bit rich. I’m gradually leaning it out. I only have a few heat cycles on the new top end so I haven’t ran the motor hard yet.
Any update on SmartCarb? How do you like it? I’m considering it for my 2012 XCW 300 but it’s a crazy investment for a bike of that age so not sure if it’s worth it. I’d appreciate your review.
Looks like Smart Carb designers have had a very close look at the operating principle of both SUs and Stromberg Zenith CD carburettors. SUs design principle goes back to 1906 when they were first patented.
Not so much. Both the SU and the Stromberg Zenith use entirely different operating principles compared to the modern SmartCarb (butterfly throttling and constant velocity piston actuation vs flat slide/metering rod fueling). SmartCarb integrated venting isn't used for throttling, but rather fuel flow assist inside of the float bowl. We hold our own patents for that and other proprietary technologies used in our fuel systems.
@@SmartCarbFuelSystems like to think that it is the exactly same principle at play, just done differently. and the end result is the same. the CV attempts to match the airspeed due to RPM, with the throttle and the load. by using the vacuum to control the slide lift it can maintain a constant velocity through the venturi, and that means it has a constant vacuum on the jet itself. regardless of RPM. or throttle setting. they still need all the tricky air circuits, and the emulsion passages, along with jets, needles, to maintain a reasonably linear fuel curve to air flow. in that regard theyre like all other carbs. from what i can tell, you guys use the vacuum in the venturi in communication with the bowl to balance the suction at the jet out, making it "constant vacuum" rather than "constant velocity". the vacuum on the needle jet reaches a certain level, and no more. regardless of how much air is sucked through or where the throttle is. that means that for any given throttle setting, with any given fuel orifice, it will always deliver the same amount of fuel in proportion to air mass, dictated by the fuel orifice and the fixed "vacuum". that is utterly different to how anyone else does it... but its still the same thing. and it will still bog if its pushed too hard and airspeed drops below a certain minimum... never had one, never torn one apart. can only assume for now. most people arent aware that the vacuum in a venturi, acting on the "jet", goes up on some log curve with airspeed, it isnt linear. but an engine, aside from VE concerns, wants a linear fueling curve. the same dose of fuel for the same amount of air, every time. yes, you dont call it a jet but for want of a better term i shall say its the same as the "needle jet". by pulling the main jet the advantage is that the fuel is far happier about being sucked up the needle jet, and the needle itself helps drag it up... big gallery to fill from a piddly little main jet... i may be wrong about all this but the fact i can bog an old mikuni up with epoxy and with some fiddling make them do what these do, tells me im on the right path.
Looked into getting one of their 4T carbs today. Said NOPE after i saw $900 😂 Cant wait to see these produced by more companies in the future at a better price point!!! Until then ill keep wrenching!
I would love to try one of these carbs and have wanted to for quite sometime, but unfortunately Lectron has scared me off. I ran their Lectron Mule with 4-1, 4-2m and 5-1 rods on my 2017 300XCW and the bottom end was terrible. Mid range and top end we’re amazing, fuel mileage was great and the bike ran clean but it just did not have the bottom end of a well tuned carb. I then bought in to their H series campaign stating 20% more power and again, that carb had no more bark off the bottom than the previous. So here we are. They have since come out with the Billetron and there’s no way I’d spend $1000CAD to test that thing despite claims of more bottom end. Smart carb has that 36mm Venturi though which is the only way I could see it being more tunable and have more bottom than the 38mm lectrons. Hard to say though. I’m a bit tainted with my experiences with Lectron and the $1000 is a lot of money to try the SC2. Wish there was more people with first hand reliable experience who could comment on the bottom end and how it compares to a well tuned Keihin 36mm. Great video though!
We're sorry to hear that Lectron has turned you off of the metering rod carburetor concept. Soft power down low has been something of a historical challenge for them. The SmartCarb's keyhole or inverted egg shaped venturi fixes that earlier design deficiency by altering the throttle rate of opening to promote stronger signal at the metering rod at lower throttle positions. The vast majority of our customers are hard enduro riders like Luis, where that bottom end power delivery is critical. Reach out with any questions - we'd be happy to put you into contact with one of our Canadian dealers as well who can share their personal experience with it.
@@SmartCarbFuelSystems appreciate the message. I like the idea of not having to rejet which allows me to focus more on riding, but part of me loves tuning a carb and getting it dialled in. I just don’t know how anything could compare to a dialled in keihin. I’ve had them all like I said and given them each ample opportunity. Lectron Mule and H series, mikuni TMX, Keihin 38mm and most recently keihin 36mm. I’ve ran JD kits and have my opinions on those but currently playing with Suzuki needles with great results. The Smart Carb would be nice to throw in there as well. We’ll see. I feel like I could write a pretty extensive reviews given all the hands on experience. PS - who is you’re Canadian dealer? Cheers
@@jaybird99100 the Keihin PWK, dialed in, is the standard by which other carbs are judged in this market/space, no doubt about that. You've tried them all except for the SmartCarb, and it doesn't compare to what you've tried. The tuning ability remains, only it's right there at your fingertips, tool-free, in seconds, trail-side, while your engine/pipe stays at operating temp. No easier carb to tune or tweak as needed. We hope you give it a try and share your experience. Send us an email or call in for contact info to our top Canadian dealer, happy to put you in touch. His name is Dan Boettger and he rides/races a KTM 250SX with 300cc top end using the SC2 SmartCarb 👌
Wouldn't mind one for my 99 model cr125 that i rebuilt and threw almost every single billet aftermarket part available on it aswell as treated her to some sm pro rim's on talon hubs, tried to build as close to a factory race bike as i could and it came out pretty nice
Parabéns por mais um excelente vídeo! Dia 10 de Abril no curso de suspensões vais dar umas dicas, já cá mora um destes para a minha Rieju ;) Grande abraço - Nuno Vidal
Muito obrigado Nuno!! E também por te juntares aos cursos 💪 tenho a certeza que vais ficar surpreendido com a ajustabilidade das tuas suspensões 😁 tens só das melhores suspensões do mercado, por isso não há como enganar 👌 E até te deixo aqui um desafio: se depois dos cursos ainda sentires a necessidade de mandar preparar suspensões, ofereço-te a mão de obra da revisão das tuas suspensões da frente 😏😁
I wish SC would publish some dyno tuning videos of their own to back up their claims, rather than relying on their sales brochure. (Corey promised this 'soon" over a year ago... In Australia, this carb is well over $1000 landed here, for a potential buyer in another country, its a lot of money to just trust some sales talk. I'm happy to run my tuned Keihin and wait for Sherco to release their EFI 2T 👍
@@StepstoPodium It's more that all a prospective buyer has to go off is somebodys word that it might be worth the money. I can appreciate the idea as a mechanic, I like that you can lay the bike down without fuel spill and it's pretty cool to look at, but I'm sure people would like to see some power pulls with the AFR readings shown to back up their claims.
Off course, it makes perfect sense. Again, that's way at the end I mentioned that I'll be doing tests to corroborate their claims, especially the mileage one, which is relatively easy to test. The performance ones I can only give a personal impression - which sometimes is more valuable than just number, imo! SmartCarb never mentions any figure about the bottom-end and I think it's where the carb shines the most, for example.
@@Danger_mouse There are several TH-camrs on here that tested it. I think the fuel saving was around 20 percent for a dirtbike rider. Just search for it.
has anyone tried lowering the float level? mine are unsupported on the air filter side, i think i'm getting fuel splashing out of the bowl from vibration at idle
Gosto de saber que os videos novos ficam na lista das coisas por tratar 😁💪 Acredito que sim! Podes sempre contactar directamente a SmartCarb e perguntar-lhes que tipo de melhorias de consumos já conseguiram obter 🙂
TPI Killer? Common Luis, that does not require much, TPI engines pretty much kill themselves 😵 On a more serious note - EXCELLENT video and I really appreciate the added graphics, without them I'd be lost. And now, that you really got me intrigued, I am very much looking forward to your future review of the smart carb. Not just the flat figures and theory, but how it compares to the Keihin? Is it worth the extra dinero??? Can't wait...
Love it Ariel 🤣🤣🤣 Thank you so much and I really appreciate the feedback! 🙌 So far it's looking really good, specially for hard enduro. That bottom end... ☺ tractability & luggability (if they're either words) are the essence of this carb 👌 Will try to do the mileage test this Sunday!
@@StepstoPodium Top explanation. I was wondering why your bike behaves like a tractor with so low RPMs and not stalling at all, amazing. Do you know why carborated (Beta, Sherco) bikes don't use this tech? Does it flood spark plugs often riding like that?
Thank you Nair! No, I haven't fouled any spark plug since I have it! I guess other manufacturers are already developing their own injection systems for 2024 (EU regulations will pretty much require it). But it's a brilliant piece of kit the smartcarb! 👀🙌
@@StepstoPodium I think that some of us will not be letting go of their carb bikes anytime soon 🤔. Using KTM as an example, their 2017 carb models have actually increased in value over the years 💸. And on a related note, I recently saw a review of the XTNG Gen3 carb. It looks identical to the smart carb, with the addition of air and fuel circuits for idle. Would love to have your take on that if you get a chance
Wonderful vídeo!!...Thanks. I like SmartCarb2,but not easy find good and easy infotmation about It.Can you make a vídeo about how World SmartCarb2 on single four stroke motor?.....and i would like if you also speak spanish. Thanks and Congratutations !!
I wish there was a smaller size available that could service the large park of carburetted, especially 50cc engines (often tuned to 70cc, especially by people who would buy a Smartcarb) and also 125cc's around Europe. These usually run the Piaggio Hiper2 2t engine. Especially in the northern parts where the temperature and altitude changes a lot, Smartcarb would be a godsend. Hopefully, this would also get the prices down a bit if they manage to achieve a large production volume. Maybe a joint venture with Malossi or Polini - who produce a lot of parts for these bikes - could be of benefit to both parties? But sadly, after eagerly waiting for a few years, there doesn't seem to be any indication that there is anything happening. They seem to be more geared towards dirt bikes. Sad.
@@SmartCarbFuelSystems Wow, that is some amazing news! Can't wait to see how it performs. I hope you also are able to work on cost lowering measures as well, as it would widen the market substantially in this class of MCs.
All carburetors need to vent their floatbowls to facilitate fuel driving pressure differentials. Conventional carburetors use external vent lines that serve two functions: they vent the float bowl and ideally they provide a way for fuel to spill in the event of a tip-over instead of flooding the engine. External vent lines, however, are longer and therefore laggier in their fluid communication into the bowl. SmartCarbs use integrated venting from right at the carb manifold, resulting in not only more proportional density communication into the float bowl but faster communication as well which is why SmartCarbs don't require accelerator pumps in 4-stroke applications.
@@StepstoPodium Okey, the shipping to Sweden is $125 from the US. Might try to get a hold of a European dealership. Maybe has more reasonable shipping fees
SC is great if you run a stock - stock ish setup with already developed engine setups by SC. they cannot accommodate heavy porting or racing pipes (cannot in sense that you need to tune from scratch) The selection of needles is limited (very) and they are very expensive. Also not all engines will be happy with a straight needles. Some need richer jetting on part throttle, some need lean and/or they need a a leaner part throttle etc... a lot of options offered no solution. They are focused on new-ish bikes, ie last 15-20 years of production where the specs haven't changed for 8-10 years. When I contacted them for an offer / assistance on purchase for a bike, and their best guess 3 needles to chose from as starting point. I got NO answer (2 years ago).
Sounds like the SmartCarb wasn't set up properly. If you still have it and wish to get the most out of it, definitely reach out to us directly for installation and tuning advice. We're happy to help.
@@SmartCarbFuelSystems I had reached out and followed all instruction. It ran well, but I didn’t like it on the bottom end and it didn’t run well with a head.
Man, it’s a shame you don’t post much anymore. This channel really should have taken off. The content is really good. I think if you played with your opening and your presentation style/energy, a little bit, did some more grinding, I really think you have talent and knowledge for a channel to really grow big.
Thank you so much for the kind words man! I really appreciate it 🙌 I'm ok with that, as long as people get the value out of them, I don't care of the channel is big or not 😄🫡
Most conventional carbs have the float chamber vent within the air inlet, this isn't an innovation. With no emulsion tube I am also suspicious of the improved atomisation claims. This design is very similar to the Blixt carbs used on speedway bikes for a number of years.
I don't get it If it's simpler in construction and does the same job much better plus has a few extra features and quality of life improvements, not to mention completely mechanical. Why don't all carbs get shipped like that from the factory?
That is precisely the question! The answer is that new technologies take time to understand, accept, and adopt at the OEM level; not to mention that any efforts like ours are met with skepticism due to a long history of other "miracle carburetors" and fuel system gizmos and gimmicks claiming to do the same thing without actually doing so, and regulatory headwinds pushing everyone to EFI. SmartCarb technology is quite new relative to prior, conventional carburetor design/function. Furthermore our technologies are patent protected, meaning only we are able to manufacture and sell carburetors like ours. And to Luis' comment, SmartCarbs are currently manufactured using CNC billet aluminum construction in the USA - a process necessary for optimal performance but also one that is rather expensive.
@@SmartCarbFuelSystems Cool so basically you guys have the patent on the tech. You should license it out to the big guys, maybe we could save carbs from going extinct. It's just a carburettor, I'm sure it doesn't have to be billet aluminum to function right.
@@1719pankaj it's not just a carburetor - it's easier. We have the smallest part count of any carb design in this space. That said the SC2 does have highly specific manufacturing/tolerancing requirements that CNC billet construction serves well; but that's no disqualification for alternative manufacturing processes if done right. There are SmartCarbs in factory engineers' hands already. Up to the big players to pick up the phone. We're waiting.
like all carb explanations, it skips past the most important aspect of all... then explains the smartcarb/elektron as vaguely as possible. emulsion tubes. the air speed through a carb is RPM dependent. the suction on a jet on a venturi increases at some logarithmic rate with air speed. engines dont tend to run at one fixed RPM. basically... at WOT, your engine can go from idle, 1200rpm or so, all the way to iunno... i got 250 i4s... 18,000rpm. the air speed from 1200 rpm to just 12000 RPM is a substantial increase for a given throat size. the fixed jet that delivers the right amount of fuel at 1200 delivers far too much at 12000. so they throw the extra circuit on, with a little tube into the throat that rams air into a little chamber around the jet and emulsion tube. as the rpm increases, and air speed increases, the fuel is forced lower and lower, uncovering more and more holes. some carbs like webers etc use an air jet and its a ratio between air leaking through the air jet and fuel from the main jet. either way, as the air speed rises from RPM, the increasing suction through the venturi is counteracted by leaking more and more air through the jet itself. that is the main puporse of the emulsion tube. its got nothing to do with "assisting atomisation". carbs work perfectly fine without emulsion tubes in fixed load and rpm situations... (anyone do control line model planes?) if you get a really underpowerd bike, load it down as much as possible, and start playing around with the holes on the emulsion tube, rather than touch the jets... you WILL feel the stumbles and bogs and hesitations through the RPM range, at any given throttle setting. throw a wideband on and do some data logs and you will start seeing how the mixture changes at various RPM depending on the size of the air jet and the position/diameter of the emulsion holes. for anyone really keen on learning this stuff, get a cheap engine on a stand, run a water pump, heavy flywheel, like a car tyre full of water, etc... really LOAD them up, so they barely accelerate... throw a mikuni VM22 on and start playing with EVERYTHING. buy a bag of jets, parts... and go to town with a soldering iron and micro drills... really hard to tune emulsion jets. theres the standard challenge of selecting the ideal jest in the first place, but this is an extra level, a "blending" of all the separate circuits, along with an unavoidable part of aerodynamics... trying to modify a log curve to match a linear one... reliably. simply. a carb is really amazing... the elektrons work on a different principle, they rely on air flow rather than air speed... tradition has always used a venturi to register air flow, but in a carb it isnt the ideal way to do it as you then rely on that vacuum to deliver the fuel... whereas working on air flow itself... pitot tubes, static and dynamic pressures... you deliver the fuel precisely as per the air mass per second...
When your oil injection messes up and completely seizes your engine and it's way more expensive to fix that and find the oil issue with it you'll reconsider a carb again.
Coming from a Mikuni TMX, you have to spend minimum $400 for a Keihin anyway. And in hard Enduro your bike loses fuel when it tips over which could leave you stranded... An extra couple hundred dollars on top of owning a dirt bike (and actually riding it, not just staring at it in the garage) in the first place really isn't that much money.
CNC billet machining in the United States is not a cheap manufacturing process but it does allow us to maintain the very tight and consistent tolerances necessary to make the best carburetor on the market.
No, in fact the SmartCarb has very little in common with the Fish. Rather it's the culmination of 50+ years of metering rod carburetor concept development pioneered by the late William "Red" Edmonston starting in the late 60s. Major differences from the Fish include the use of a dual-gate flat slide (not a butterfly with in-built emulsion tube) and patented features including the metering rod (single circuit with no additional circuits or pumpers), variable throttle rate venturi (algorithmically derived), and integrated float bowl venting communicating at-manifold air density and velocity into the float bowl (not a simple vent tube).
It's very different from the SU. Unlike the SU the SmartCarb is directly throttled using a flat slide, not a butterfly/constant velocity piston setup. Unlike the SU it vents what is essentially MAP density communication from inside of the airboot into the float bowl to drive fuel flow - not to throttle the carb. If there are similarities they begin and end at the use of a float bowl and they both mix air and fuel for internal combustion applications.
This just shows that carburetors are not outdated they just need improvement. Thanks for the vid my friend.
See the price. You can convert to fuel injection it's cheaper lol
@@littlereptilian7580 less parts to break though and no high pressure e pump as well. Never was a fan myself everything I own is air cooled and carbureted.
@@andystoolbox I wanted to Install two of these on my dr800. They are more expensive than my bike hahahaha. But if I win the lottery I will to it
Awesome video, extremely well, and simple explanations! Used to run SmartCarb 2 in my last 300XC KTM, and was like magic! Couldn't explain how crisp the bike was compared to Mikuni and Keihin, no matter where I rode, doing nothing. 🙄🙄
Thank you so much! 😄🙌
Couldn't agree with you more!
Awesome video! The best I've seen on any carb! Good job with the animations also!
Thank you so much! 🙏
Your diagrams are great, finally a video that allows me to understand how this carburetor works!
I'm going to make some adjustments on my Keihin and why not try the SmartCarb later 😏
Thank you so much!!
I have a video for that that well eheh 😁
Listen man, THIS CHANNEL HAS THE BEST VISUAL EXPLANATIONS OUT OF ANY CHANNEL ON TH-cam! OUTSTANDING ANIMATIONS!!
PLEASE KEEP THEM COMING!
Do you have a PATREON page? I would love to support this channel!
Thank you so so much Tony!! 🙏❤
I really appreciate it 💪
I don't have one actually, but if you you'd like to get some merch, it would help the channel, for sure 🙌
That's a complete video on how it works .. could not add anything else. Great job !
Appreciate the good word Daniel!😄
That's why I choose carburetor over Fuel injection...
The "scoop" as you call it serves a much more important purpose than you mention.
It's purpose it to capture the dynamic pressure ("ram air" pressure) of the air entering the carb. Without it the carb would go lean at higher throttle openings. The Lectron uses a second, adjustable, jet and nozzle to deliver extra fuel at high throttle openings, the Smartcarb uses the dynamic pressure of the air's movement to pressurise the float bowl and deliver extra fuel.
I did mention but I appreciate the comment! 😄💪
@@StepstoPodium You mentioned it as part of the altitude compensation mechanism but it's integral to the way the carb works.
@@Surestick88 well said!
Thanks dude, that clears that up 4 me in my mind
Excelente video, como sempre!! Qualquer um consegue ficar a perceber como funciona, espetacular!
Fico mesmo contente por ouvir isso!! Muito obrigado 💪💪
Another excellent video. I really wish they would make a drop-in replacement for older 4 strokes like the XR250R and XR400R. I'd buy one in a minute.
Thank you!!
I wait to make one for Suzuki 650dr ❤
Great explanation, thank you. I need one of these for my GasGas.
Para quem gosta de ver com legendas em Português, carreguem no icone do lado esquerdo das "Definições" :)
These videos are amazing 👏🏻 so well done and really well explained. Thanks
Thank you so so much benny! I really appreciate it 💪😃
Your videos are always high quality material! 💪
Thank you so much Nuno!! Always a pleasure to have you here! 😄🙌
Excellent job my friend. Very well documented.
Thank youuu!! 🙌🙂
Goddayumn this bro never disappoints! Leading the fore front of dirtbike engineering explanation on the world for sure! what a genius ideia this carb design is!
Thank you João!!! 🙌🙌🙌
Great video, especially with the animated views and explanations of how the carbs function. To me, a big downside to the Smart Carb is that they recommend a complete servicing every year or two (for a cost of approx $200.00). The hassle and expense (as well as down time for shipping, etc) is a big drawback. I've never had to send in a standard carb for servicing, even with 10+ years and 350+ hours of ride time.
The other negative is the installation process. Having to remove and then cut/trim the air boot is more than most people want to deal with (including myself). The Lectron carb does not require any of that for installation. Lectron also needs servicing once in a while, but I don't think as often as the Smart Carb.
Not sure where you're getting that information but SmartCarbs do not need to be sent in for servicing. We do recommend a thorough cleaning with hot, soapy water, carb cleaner, and compressed air once a year - especially if the carb has sat for some time without use. Rebuild kits containing all service parts (o-rings, gaskets, etc) are available and a rebuild is recommended every 2-3 years. That's something anyone can do with a handful of common tools. SmartCarbs have the smallest part count of any carburetor in this space and require no more maintenance or servicing than any other carburetor.
What you may be thinking of is our Factory Refurbishing service which is $200. It's not typically recommended or required unless the carb is in really poor shape or is quite old. It involves a full tear-down, sonic cleaning, rebuild with all service parts replaced, and reset to any factory baseline tune specific to the bike it's to be installed into. That's a service we offer for any billet SmartCarb owner, new or used, and those choosing to use it can be sure that their SmartCarb has been thoroughly inspected and checked through by our technicians.
You don't need to remove the airboot to perform the trim for proper internal venting in the SmartCarb. We recommend pivoting the subframe up and out of the way and the trim, if even required (Betas do not require it), can be made very easily in under 10 minutes. We recommend a dremel tool with a barrel sander. The trim doesn't compromise the integrity of the airboot nor does it affect the performance of any other carburetor - but it does ensure that the SmartCarb is venting properly, which is critical for top end fuel flow (SmartCarbs need no power jet like the Lectron does) and more complete air density compensation. The installation videos on our channel provide step-by-step instructions.
@@SmartCarbFuelSystems Thank you for clarifying this. I looked again at the SmartCarb website and realized that I misinterpreted the maintenance guidelines that were listed. I would still rather not have to do even a "basic servicing", considering that I've never had to do that on a stock carb, even with hundreds of hours on it.
As for removing the airboot to perform the trimming, I got that from the video put out by SmartCarb, for a 2019 KTM 300XC.
th-cam.com/video/qp7VNc3RhPI/w-d-xo.html
All that said, I am still considering at some point trying the SmartCarb on my 2019 KTM 250XC. I recently installed the new Lectron Billetron carb, but might still try the SmartCarb one of these days to see if it performs better than the Lectron.
@@waynemodesitt3445 the maintenance guidelines we provide are merely suggestions. If you ride often and don’t let fuel sit in the carb and avoid ethanol if you can then there is minimal maintenance required. Just keep it clean and do that rebuild as needed (typically around 3 years depending on use).
Your KTM would require the boot trim but again it’s very easy to do, you only do it once, and we are available to answer any questions you may have. Our Quick Start Guide, included with every purchase, provides a visual way to confirm proper trimming.
Regarding the SmartCarb vs Billetron you might check out this recent video comparing the two on a Sherco 300 SE: th-cam.com/video/rPEBhnSyxbo/w-d-xo.html
@@SmartCarbFuelSystems I watched that video a few days ago (comparing the SmartCarb vs Billetron). I was having similar issues with the Billetron (leaking seals, plus several adjustments leaner on the metering rod, and I'm still getting some oil out the back of the silencer). That video is what made me consider trying out the SmartCarb, especially if it really does perform better than the Billetron, particularly at low rpm (I ride a lot of tight/technical singletrack).
How does one go about avoiding ethanol here in California? Other than buying race gas, I don't see a way around it. I do drain the carb if my bike is going to sit for more than a week or two.
@@waynemodesitt3445 Hard to avoid ethanol in CA no doubt. If you can't avoid it then we simply recommend that you ride frequently and cycle new fuel through the fuel system. Don't let it sit for too long. If you store the bike long-term then either using a stabilizer or draining the carb are recommended, though we tend to want to leave fuel in it to prolong the life of the o-rings.
Per SmartCarbs recommendations; when transporting or if you lay the bike over for more than a few seconds, turn off the fuel petcock to avoid the possibility of fuel running into the crankcase via the fuel nozzle/slide. This is no big deal and should be done on a traditional carb as well or else it will piss fuel out the overflow vents. I just ordered a SC2 for my 18 TE 250, and am looking forward to getting to know it. 👍🏻
How is it going with sc2?
@@TubolMotoadventures I just did a fresh top end and mounted the SC2. I’ve only got about 30-40 minutes on it so far and as expected it is a bit rich. I’m gradually leaning it out. I only have a few heat cycles on the new top end so I haven’t ran the motor hard yet.
@@evr-mr3cpwhat are your opinions about it now?
Any update on SmartCarb? How do you like it? I’m considering it for my 2012 XCW 300 but it’s a crazy investment for a bike of that age so not sure if it’s worth it. I’d appreciate your review.
I have a couple of videos talking about the smartcarb pn the channel :)
Wow! Excellent description!
Thank you!! 😄🙌
Excellent explanation.
Thank you!!
Looks like Smart Carb designers have had a very close look at the operating principle of both SUs and Stromberg Zenith CD carburettors. SUs design principle goes back to 1906 when they were first patented.
Not so much. Both the SU and the Stromberg Zenith use entirely different operating principles compared to the modern SmartCarb (butterfly throttling and constant velocity piston actuation vs flat slide/metering rod fueling). SmartCarb integrated venting isn't used for throttling, but rather fuel flow assist inside of the float bowl. We hold our own patents for that and other proprietary technologies used in our fuel systems.
@@SmartCarbFuelSystems like to think that it is the exactly same principle at play, just done differently.
and the end result is the same.
the CV attempts to match the airspeed due to RPM, with the throttle and the load. by using the vacuum to control the slide lift it can maintain a constant velocity through the venturi, and that means it has a constant vacuum on the jet itself. regardless of RPM. or throttle setting.
they still need all the tricky air circuits, and the emulsion passages, along with jets, needles, to maintain a reasonably linear fuel curve to air flow. in that regard theyre like all other carbs.
from what i can tell, you guys use the vacuum in the venturi in communication with the bowl to balance the suction at the jet out, making it "constant vacuum" rather than "constant velocity". the vacuum on the needle jet reaches a certain level, and no more. regardless of how much air is sucked through or where the throttle is. that means that for any given throttle setting, with any given fuel orifice, it will always deliver the same amount of fuel in proportion to air mass, dictated by the fuel orifice and the fixed "vacuum".
that is utterly different to how anyone else does it... but its still the same thing.
and it will still bog if its pushed too hard and airspeed drops below a certain minimum...
never had one, never torn one apart. can only assume for now. most people arent aware that the vacuum in a venturi, acting on the "jet", goes up on some log curve with airspeed, it isnt linear. but an engine, aside from VE concerns, wants a linear fueling curve. the same dose of fuel for the same amount of air, every time.
yes, you dont call it a jet but for want of a better term i shall say its the same as the "needle jet".
by pulling the main jet the advantage is that the fuel is far happier about being sucked up the needle jet, and the needle itself helps drag it up... big gallery to fill from a piddly little main jet...
i may be wrong about all this but the fact i can bog an old mikuni up with epoxy and with some fiddling make them do what these do, tells me im on the right path.
Looked into getting one of their 4T carbs today. Said NOPE after i saw $900 😂
Cant wait to see these produced by more companies in the future at a better price point!!! Until then ill keep wrenching!
Keep on wrenching Phil!
really nice explanation, top graphics!!!
Thaaank you Max! 😄🙌
Keihin float bowl also communicate with atmosphere. Why doesn’t have elevation and temperature compensation?
They do, but they're not pressurised! That's why the SmartCarb compensates for air density variations :)
@@StepstoPodium I'm understand. thank you
I would love to try one of these carbs and have wanted to for quite sometime, but unfortunately Lectron has scared me off. I ran their Lectron Mule with 4-1, 4-2m and 5-1 rods on my 2017 300XCW and the bottom end was terrible. Mid range and top end we’re amazing, fuel mileage was great and the bike ran clean but it just did not have the bottom end of a well tuned carb. I then bought in to their H series campaign stating 20% more power and again, that carb had no more bark off the bottom than the previous. So here we are. They have since come out with the Billetron and there’s no way I’d spend $1000CAD to test that thing despite claims of more bottom end. Smart carb has that 36mm Venturi though which is the only way I could see it being more tunable and have more bottom than the 38mm lectrons. Hard to say though. I’m a bit tainted with my experiences with Lectron and the $1000 is a lot of money to try the SC2. Wish there was more people with first hand reliable experience who could comment on the bottom end and how it compares to a well tuned Keihin 36mm. Great video though!
Thank you! 🙏 You might be surprised with my next video giving some feedback while riding hard enduro 💪
We're sorry to hear that Lectron has turned you off of the metering rod carburetor concept. Soft power down low has been something of a historical challenge for them. The SmartCarb's keyhole or inverted egg shaped venturi fixes that earlier design deficiency by altering the throttle rate of opening to promote stronger signal at the metering rod at lower throttle positions. The vast majority of our customers are hard enduro riders like Luis, where that bottom end power delivery is critical.
Reach out with any questions - we'd be happy to put you into contact with one of our Canadian dealers as well who can share their personal experience with it.
@@StepstoPodium - I’m going to subscribe. I’m curious for sure. Cheers.
@@SmartCarbFuelSystems appreciate the message. I like the idea of not having to rejet which allows me to focus more on riding, but part of me loves tuning a carb and getting it dialled in. I just don’t know how anything could compare to a dialled in keihin. I’ve had them all like I said and given them each ample opportunity. Lectron Mule and H series, mikuni TMX, Keihin 38mm and most recently keihin 36mm. I’ve ran JD kits and have my opinions on those but currently playing with Suzuki needles with great results. The Smart Carb would be nice to throw in there as well. We’ll see. I feel like I could write a pretty extensive reviews given all the hands on experience. PS - who is you’re Canadian dealer? Cheers
@@jaybird99100 the Keihin PWK, dialed in, is the standard by which other carbs are judged in this market/space, no doubt about that. You've tried them all except for the SmartCarb, and it doesn't compare to what you've tried. The tuning ability remains, only it's right there at your fingertips, tool-free, in seconds, trail-side, while your engine/pipe stays at operating temp. No easier carb to tune or tweak as needed.
We hope you give it a try and share your experience. Send us an email or call in for contact info to our top Canadian dealer, happy to put you in touch. His name is Dan Boettger and he rides/races a KTM 250SX with 300cc top end using the SC2 SmartCarb 👌
I wonder if i could just 3d print some stuff and modify the carb a little to have a vent for a vacuum advance I could put it on an old car.
Wouldn't mind one for my 99 model cr125 that i rebuilt and threw almost every single billet aftermarket part available on it aswell as treated her to some sm pro rim's on talon hubs, tried to build as close to a factory race bike as i could and it came out pretty nice
Sweeeeet 👌
Looking forward on the stroke smart carb
Parabéns por mais um excelente vídeo! Dia 10 de Abril no curso de suspensões vais dar umas dicas, já cá mora um destes para a minha Rieju ;) Grande abraço - Nuno Vidal
Muito obrigado Nuno!!
E também por te juntares aos cursos 💪 tenho a certeza que vais ficar surpreendido com a ajustabilidade das tuas suspensões 😁 tens só das melhores suspensões do mercado, por isso não há como enganar 👌
E até te deixo aqui um desafio: se depois dos cursos ainda sentires a necessidade de mandar preparar suspensões, ofereço-te a mão de obra da revisão das tuas suspensões da frente 😏😁
Great invention 🇺🇸
I wish SC would publish some dyno tuning videos of their own to back up their claims, rather than relying on their sales brochure.
(Corey promised this 'soon" over a year ago...
In Australia, this carb is well over $1000 landed here, for a potential buyer in another country, its a lot of money to just trust some sales talk.
I'm happy to run my tuned Keihin and wait for Sherco to release their EFI 2T 👍
Fair enough! The custom taxes really hit the end customer and at the end, the company. That's how the world goes, but I feel you! 🙌
@@StepstoPodium
It's more that all a prospective buyer has to go off is somebodys word that it might be worth the money.
I can appreciate the idea as a mechanic, I like that you can lay the bike down without fuel spill and it's pretty cool to look at, but I'm sure people would like to see some power pulls with the AFR readings shown to back up their claims.
Off course, it makes perfect sense.
Again, that's way at the end I mentioned that I'll be doing tests to corroborate their claims, especially the mileage one, which is relatively easy to test. The performance ones I can only give a personal impression - which sometimes is more valuable than just number, imo!
SmartCarb never mentions any figure about the bottom-end and I think it's where the carb shines the most, for example.
@@Danger_mouse There are several TH-camrs on here that tested it. I think the fuel saving was around 20 percent for a dirtbike rider. Just search for it.
Nice video well explained. A comparison with the Lectron would be nice.
Thank you! I tried to reach them, but got no answer 🤷♂️
Simple but genius at the same time 👌🏻
True indeed!!
Was checking which is worth going for my Yamaha RZ350 with a 421cc upgrades for a Carburetor the Billetron or the Smart Carb
Now I want one!
Great video, keep up the good work!
Thank you John! I really appreciate it! 😄
The diagrams are awesome!!!
Thank you!!
already answered, thank you ❤️👍
has anyone tried lowering the float level? mine are unsupported on the air filter side, i think i'm getting fuel splashing out of the bowl from vibration at idle
Thanks
Tooooop your vídeo 👏🏻👏🏻👏🏻👏🏻i am Brasilian…👍
Obrigado!! 😄🙌
Vais me fazer gastar dinheiro :)
Vídeo top como sempre
Eu não quero nada 😅🤣
Muito obrigado grande Bruno 💪
Olá Luís !
Estava agora a ver este vídeo que tinha em atraso e isso de facto parece maravilhoso !
Achas que numa Sherco 125 SE-R compensa ?
Gosto de saber que os videos novos ficam na lista das coisas por tratar 😁💪
Acredito que sim! Podes sempre contactar directamente a SmartCarb e perguntar-lhes que tipo de melhorias de consumos já conseguiram obter 🙂
Um luxo como sempre! Temos de falar sobre como e que fazes essas tuas animações 🤷♂🤯❤😅
Muito obrigado! 🙌💪
Faço tudo à mão após 100horas de edição e produção... só mesmo maluco é que faco 🤪
@@StepstoPodium e pah.. 🤯 tava convencido que tinhas ai um programa todo bonito.. afinal o programa és tu 😅
Se encontrares esse programa, avisa-me, pago peso de ouro po ele! 😅🤣
Aguardo entao pelos proximos videos para fazermos negocio 😁
TPI Killer? Common Luis, that does not require much, TPI engines pretty much kill themselves 😵
On a more serious note - EXCELLENT video and I really appreciate the added graphics, without them I'd be lost.
And now, that you really got me intrigued, I am very much looking forward to your future review of the smart carb. Not just the flat figures and theory, but how it compares to the Keihin? Is it worth the extra dinero??? Can't wait...
Love it Ariel 🤣🤣🤣
Thank you so much and I really appreciate the feedback! 🙌
So far it's looking really good, specially for hard enduro. That bottom end... ☺ tractability & luggability (if they're either words) are the essence of this carb 👌
Will try to do the mileage test this Sunday!
@@StepstoPodium Top explanation. I was wondering why your bike behaves like a tractor with so low RPMs and not stalling at all, amazing. Do you know why carborated (Beta, Sherco) bikes don't use this tech? Does it flood spark plugs often riding like that?
Thank you Nair!
No, I haven't fouled any spark plug since I have it!
I guess other manufacturers are already developing their own injection systems for 2024 (EU regulations will pretty much require it). But it's a brilliant piece of kit the smartcarb! 👀🙌
@@StepstoPodium I think that some of us will not be letting go of their carb bikes anytime soon 🤔. Using KTM as an example, their 2017 carb models have actually increased in value over the years 💸. And on a related note, I recently saw a review of the XTNG Gen3 carb. It looks identical to the smart carb, with the addition of air and fuel circuits for idle. Would love to have your take on that if you get a chance
Indeed! People still value simplicity in offroad.
I heard avout it and hope Ill tske a look some day 😆
Wonderful vídeo!!...Thanks.
I like SmartCarb2,but not easy find good and easy infotmation about It.Can you make a vídeo about how World SmartCarb2 on single four stroke motor?.....and i would like if you also speak spanish.
Thanks and Congratutations !!
Thank you!
Smartcarb doesn't have any carb for 4-strokes... 😬
I have a lil' question : Can it be adapted for car engines ?
It's a matter of contacting SmartCarb directly, they'll be able to answer that for sure :)
Now if they would get the price more affordable
💯
does this smart carb can be use to a 4stroke motorcycle?
Dont think so!
I wish there was a smaller size available that could service the large park of carburetted, especially 50cc engines (often tuned to 70cc, especially by people who would buy a Smartcarb) and also 125cc's around Europe. These usually run the Piaggio Hiper2 2t engine.
Especially in the northern parts where the temperature and altitude changes a lot, Smartcarb would be a godsend. Hopefully, this would also get the prices down a bit if they manage to achieve a large production volume. Maybe a joint venture with Malossi or Polini - who produce a lot of parts for these bikes - could be of benefit to both parties? But sadly, after eagerly waiting for a few years, there doesn't seem to be any indication that there is anything happening. They seem to be more geared towards dirt bikes. Sad.
We plan to have a 17-19-21mm size SC2 family in production this summer to serve 50-70cc applications. Stay tuned!
@@SmartCarbFuelSystems Wow, that is some amazing news! Can't wait to see how it performs.
I hope you also are able to work on cost lowering measures as well, as it would widen the market substantially in this class of MCs.
What is purpose of 4 spoilage hose in normal carburettor?how it works 6:41
It's to avoid flooding the engine
All carburetors need to vent their floatbowls to facilitate fuel driving pressure differentials. Conventional carburetors use external vent lines that serve two functions: they vent the float bowl and ideally they provide a way for fuel to spill in the event of a tip-over instead of flooding the engine. External vent lines, however, are longer and therefore laggier in their fluid communication into the bowl. SmartCarbs use integrated venting from right at the carb manifold, resulting in not only more proportional density communication into the float bowl but faster communication as well which is why SmartCarbs don't require accelerator pumps in 4-stroke applications.
Hey 👋🏼
Did you buy your smartcarb in Europe?
Hey! It was shipped from SmartCarb
@@StepstoPodium Okey, the shipping to Sweden is $125 from the US.
Might try to get a hold of a European dealership. Maybe has more reasonable shipping fees
Tem um grande defeito esses carburadores.
O Preço 😂
Yes)
Sobre isso já não me cabe a mim dizer 😶😆
Can’t I use this carburetor for four stroke bike
How much are they going for in usd i guess even though im in Australia
I have no idea 😬
Boa tarde,também dá para adaptar a uma DRZ400 E de 2002 e qual é o preço? Obrigado
Olá Miguel! Não faco ideia, mas se fores ao site deles (na descrição) podes ver se é compatível ou não 💪
@@StepstoPodium obrigado
Sooo would it work to put 8 of them on a V8?
Maybe! Get in touch with them 😄
SC is great if you run a stock - stock ish setup with already developed engine setups by SC. they cannot accommodate heavy porting or racing pipes (cannot in sense that you need to tune from scratch)
The selection of needles is limited (very) and they are very expensive. Also not all engines will be happy with a straight needles. Some need richer jetting on part throttle, some need lean and/or they need a a leaner part throttle etc... a lot of options offered no solution.
They are focused on new-ish bikes, ie last 15-20 years of production where the specs haven't changed for 8-10 years.
When I contacted them for an offer / assistance on purchase for a bike, and their best guess 3 needles to chose from as starting point. I got NO answer (2 years ago).
You should definitely hit them up again, they have one of the best customer support out there
Can I use it in an old VW Beetle?
You should contact smartcarb for those infos 😊
Its a spray gun haha love it
You should compare with lectron
For me, a 50 hour piston with a smartcarb looked much much worse than 100 hour with stock keihin.
Sounds like the SmartCarb wasn't set up properly. If you still have it and wish to get the most out of it, definitely reach out to us directly for installation and tuning advice. We're happy to help.
@@SmartCarbFuelSystems I had reached out and followed all instruction. It ran well, but I didn’t like it on the bottom end and it didn’t run well with a head.
Man, it’s a shame you don’t post much anymore. This channel really should have taken off. The content is really good. I think if you played with your opening and your presentation style/energy, a little bit, did some more grinding, I really think you have talent and knowledge for a channel to really grow big.
Thank you so much for the kind words man! I really appreciate it 🙌
I'm ok with that, as long as people get the value out of them, I don't care of the channel is big or not 😄🫡
its a shame they dont sell these on a 4 carb set up for inline 4's
Most conventional carbs have the float chamber vent within the air inlet, this isn't an innovation.
With no emulsion tube I am also suspicious of the improved atomisation claims.
This design is very similar to the Blixt carbs used on speedway bikes for a number of years.
Friend, your Portuguese subtitles are marked as English. My translator is going crazy. Please fix it.
Damn! I'll take a look at it, thank you!
fixed :)
I don't get it
If it's simpler in construction and does the same job much better plus has a few extra features and quality of life improvements, not to mention completely mechanical.
Why don't all carbs get shipped like that from the factory?
Cost most likely!
That is precisely the question!
The answer is that new technologies take time to understand, accept, and adopt at the OEM level; not to mention that any efforts like ours are met with skepticism due to a long history of other "miracle carburetors" and fuel system gizmos and gimmicks claiming to do the same thing without actually doing so, and regulatory headwinds pushing everyone to EFI. SmartCarb technology is quite new relative to prior, conventional carburetor design/function. Furthermore our technologies are patent protected, meaning only we are able to manufacture and sell carburetors like ours.
And to Luis' comment, SmartCarbs are currently manufactured using CNC billet aluminum construction in the USA - a process necessary for optimal performance but also one that is rather expensive.
Thank you for chippin in Nathan 🙂
@@SmartCarbFuelSystems
Cool so basically you guys have the patent on the tech.
You should license it out to the big guys, maybe we could save carbs from going extinct.
It's just a carburettor, I'm sure it doesn't have to be billet aluminum to function right.
@@1719pankaj it's not just a carburetor - it's easier. We have the smallest part count of any carb design in this space. That said the SC2 does have highly specific manufacturing/tolerancing requirements that CNC billet construction serves well; but that's no disqualification for alternative manufacturing processes if done right. There are SmartCarbs in factory engineers' hands already. Up to the big players to pick up the phone. We're waiting.
Someone send me 8 larger versions of this smart carb so I can do individual throttle bodies on an ls motor 😂
Psi big air looks pretty much the same
Not exactly, but it was close enough to warrant legal action. We don't take kindly to infringement on our IP.
Acho q nem vou procurar o preço desse bichinho x)
U
like all carb explanations, it skips past the most important aspect of all... then explains the smartcarb/elektron as vaguely as possible.
emulsion tubes.
the air speed through a carb is RPM dependent. the suction on a jet on a venturi increases at some logarithmic rate with air speed.
engines dont tend to run at one fixed RPM.
basically... at WOT, your engine can go from idle, 1200rpm or so, all the way to iunno... i got 250 i4s... 18,000rpm. the air speed from 1200 rpm to just 12000 RPM is a substantial increase for a given throat size. the fixed jet that delivers the right amount of fuel at 1200 delivers far too much at 12000. so they throw the extra circuit on, with a little tube into the throat that rams air into a little chamber around the jet and emulsion tube. as the rpm increases, and air speed increases, the fuel is forced lower and lower, uncovering more and more holes. some carbs like webers etc use an air jet and its a ratio between air leaking through the air jet and fuel from the main jet.
either way, as the air speed rises from RPM, the increasing suction through the venturi is counteracted by leaking more and more air through the jet itself. that is the main puporse of the emulsion tube. its got nothing to do with "assisting atomisation". carbs work perfectly fine without emulsion tubes in fixed load and rpm situations... (anyone do control line model planes?)
if you get a really underpowerd bike, load it down as much as possible, and start playing around with the holes on the emulsion tube, rather than touch the jets... you WILL feel the stumbles and bogs and hesitations through the RPM range, at any given throttle setting. throw a wideband on and do some data logs and you will start seeing how the mixture changes at various RPM depending on the size of the air jet and the position/diameter of the emulsion holes.
for anyone really keen on learning this stuff, get a cheap engine on a stand, run a water pump, heavy flywheel, like a car tyre full of water, etc... really LOAD them up, so they barely accelerate... throw a mikuni VM22 on and start playing with EVERYTHING. buy a bag of jets, parts... and go to town with a soldering iron and micro drills...
really hard to tune emulsion jets. theres the standard challenge of selecting the ideal jest in the first place, but this is an extra level, a "blending" of all the separate circuits, along with an unavoidable part of aerodynamics... trying to modify a log curve to match a linear one... reliably. simply. a carb is really amazing...
the elektrons work on a different principle, they rely on air flow rather than air speed... tradition has always used a venturi to register air flow, but in a carb it isnt the ideal way to do it as you then rely on that vacuum to deliver the fuel... whereas working on air flow itself... pitot tubes, static and dynamic pressures... you deliver the fuel precisely as per the air mass per second...
im having a horrible time tuning mine.
I didn't have it easy as well, but contact them, they will help you a lot in getting it dialed!
Please contact SmartCarb Fuel Systems for assistance in tuning your SmartCarb. We're happy to help!
Had a 2019 TPI, and currently a 2022 TPI. I would never go back to carbs. Especially with a Coober ECU. It's not 1984 anymore
When your oil injection messes up and completely seizes your engine and it's way more expensive to fix that and find the oil issue with it you'll reconsider a carb again.
@@cheddarshredder6572 money isn't a concern broski
🤣🤣🤣🤣🤣🤣🤣🤣
$700 a piece. Pass.
Coming from a Mikuni TMX, you have to spend minimum $400 for a Keihin anyway. And in hard Enduro your bike loses fuel when it tips over which could leave you stranded... An extra couple hundred dollars on top of owning a dirt bike (and actually riding it, not just staring at it in the garage) in the first place really isn't that much money.
Can u now explain why it costs so much? Hahahaha
CNC billet machining in the United States is not a cheap manufacturing process but it does allow us to maintain the very tight and consistent tolerances necessary to make the best carburetor on the market.
Old concept dusted off.
en.wikipedia.org/wiki/Reece_Fish_Carburettor
No, in fact the SmartCarb has very little in common with the Fish. Rather it's the culmination of 50+ years of metering rod carburetor concept development pioneered by the late William "Red" Edmonston starting in the late 60s. Major differences from the Fish include the use of a dual-gate flat slide (not a butterfly with in-built emulsion tube) and patented features including the metering rod (single circuit with no additional circuits or pumpers), variable throttle rate venturi (algorithmically derived), and integrated float bowl venting communicating at-manifold air density and velocity into the float bowl (not a simple vent tube).
Knowledge shot right there.
Its not much different to an SU
It's very different from the SU. Unlike the SU the SmartCarb is directly throttled using a flat slide, not a butterfly/constant velocity piston setup. Unlike the SU it vents what is essentially MAP density communication from inside of the airboot into the float bowl to drive fuel flow - not to throttle the carb. If there are similarities they begin and end at the use of a float bowl and they both mix air and fuel for internal combustion applications.