Smart Carb vs Keihin Carb - Better than Fuel Injection?!

[@SmartCarbFuelSystems]

Thanks James! A word on the smooth power delivery: SmartCarbs are single circuit carburetors. The fueling is controlled by a single circuit idle to WOT using a metering rod which means there are no transitions between multiple circuits (pilot, main, needle) like in the Keihin or other conventional carbs. You get one smooth, linear, fuel curve designed specifically for the fueling needs and combustion efficiency of your 300 2T, or any other 2T we equip. All you have to do is adjust it for the best idle and off idle response using the top clicker - takes seconds to do trailside. The specific grind of the metering rod and the SmartCarb’s integrated float bowl venting handle fueling through the mid to top. Regarding the power, smoother doesn’t necessarily mean less. The “hit” of the Keihin is just one way to perceive it - how we feel it while riding and for most people it’s a familiar thing they’ve experienced on their bikes for years. With the SmartCarb you’re getting the same grunt, only it’s smoothed out. The claimed power gains present themselves in other more telling ways, like being able to run taller gearing, short shifting, tractoring through in a higher gear than you could before, and of course by throwing the bike on the dyno. It’s worth noting that Cody and Keith both used the SmartCarb in competition throughout this last AMA Extreme season. We believe that this fuel system rivals FI, or more specifically TPI/TBI in terms of performance, fuel economy, and ease of use. Stay tuned while we continue to prove that out!

[@1armenduro]

I'm going to be racing enduro this year (my first season) and having only one arm I drop my bike soooo much! Every time I do that I lose a ton of fuel! Can wait to get one of these beauts on my Sherco.....unfortunately I need to find £6,500 for a bespoke arm brace first so I won't be fitting one any time soon but kudos on a fantastic piece of kit Smart Carb! And as always, great video James!💪

[@SmartCarbFuelSystems]

@@1armenduro thank you for your comment and kind words. Please reach out to us directly.

[@1armenduro]

@@SmartCarbFuelSystems what's the best email to reach you guys on?

[@mbalunovic]

1st of, stop pushing the misconception that a circuit in a conventional carb "kicks in" at any setting. All are effective at all of the time. You don't believe the Main jet effects Idle, well adjust for prefect idle and than take out the main jet. Report back what you have found. Same goes for every circuit component. Yes a main jet will effect idle to much less degree than it will effect WOT but it is effecting it. already from 1/4 throttle he MJ has significant influence on jetting. You say that the carb handles the top and mid range, yet there are multiple metering rod types with different WOT richness specs. also not al displacements will need the same on a single carb. Yet you forget to mention that the metering rod has to be selected for a particular bike in order for it to work properly. When I enquired for a specific bike that's not "off he mill" you haven't even responded at all, let alone with appropriate metering rod range what was the enquiry.

[@SmartCarbFuelSystems]

@@mbalunovic you misunderstand us. Yes all circuits are active at all times in a conventional jet/needle carburetor, but their effectiveness varies throughout the throttle range with circuits going into and out of their maximum effect. That was our point as it compares to the SmartCarb which uses one single circuit. Omission isn't deception. Of course we pre-select the correct metering rod for the applications needs, taking into account the engine's characteristics, engine/exhaust modifications, riding style(s), and fuel selection/oil mix ratio. We require that information from every customer and are always happy to advise users on correct metering rod selection for their needs, even offering an exchange program for metering rods for new or second-hand owners. We have never claimed that one metering rod will sufficiently fuel any application. We have series of metering rods with varying grind angles (fuel profiles) to handle the fueling needs of a wide variety of applications. With the correct fuel profile in place the customer needs only position it for the best idle/off-idle response, tuning from the bottom up. Provided that has happened then yes, the metering rod and internal float bowl venting will handle fueling mid to top. At that point the only reason to change the metering rod out to change the top end fueling would be for major engine modification (compression in particular) and/or changing to race fuels, particularly oxygenated race fuels. Lastly, we can't find your name in any of our email accounts or social media messages. Regret that you may have been left unanswered, but we encourage you to try again. Happy to tell you whether or not we have a SmartCarb solution developed yet for your application.

[@jeffhartman7545]

I put a Smart Carb on my Sherco 300 as well. I played the tuning game with my OEM Kehin and tho I feel it was good, the SC2 was hands down better. Butter smooth bottom end and nice linear transition to the top end while losing nothing over the Kehin. In fact I'd bet the power increased everywhere in the rpm range. It's a cleaner setup and range should be better but I cannot confirm that. I really like the exterior adjustability. It's been set since installed and never needed to be touched again regardless of temperature or altitude. I love mine!

[@InsideEnduro]

That is awesome! Keihin carb is great but the guys over at smart carb are doing something special.

[@JeremyFoytik]

Love my 36 SC2, been running her well over a year now on a 00 CR250. So smooth and great on fuel.

[@InsideEnduro]

Fuel mileage is a huge plus!!!

[@JeremyFoytik]

No doubt, I think I could almost go back to my stock tank for my XC races and Hard Enduros.

[@racesla]

Put a 36 sc2 on my 2019 Beta 300RR race, love it. Much better range, no loss of bottom end power that seems to come with the Lectrons. In fact I think it may have a little more botton end hit now. Just got my ticket, should look bitchin next to my 300 sef. Cheers James

[@InsideEnduro]

Ohh yeah add to the Sherco quiver!

[@andrewsoldan6050]

honestly I am very happy with stock carb on my sherco 300e. It has character.

[@InsideEnduro]

Stock carb is great!!!

[@rafy600]

Also adjust it self for different temp and altitude after is dial in. Have it on my Sherco 2021 working great. Fuel economy is real and the bike feels less powerful downd low which for hard Enduro its translate to more traction. Good video as always 👍 👌

[@InsideEnduro]

The fuel economy is sick!!!

[@danweldon3506]

I'm picturing myself tearing that beautiful Christmas wrapping off that awesome bike with kid like excitement! lol Thanks James and crew! Love what you're doing!!

[@InsideEnduro]

Thanks Dan!!!!!

[@thatfast3002]

I never tried a smart carb but the air striker is awesome I don't need to try anything else

[@Ozfreerider_adventures]

It’s Probbaly smoother because it doesn’t switch from one jet to another

[@Johnr37us]

Well thank you for putting that on my bike. Let’s hope that’s what I get to say to you in a few days . I purchased a ticket to try to win that sweet looking 2022 Sherco 300 on the 17th.

[@InsideEnduro]

Heck yeah John!!! One day away from knowing!!!

[@mrmauco]

Bought one and felt that the power delivery became too aggressive and had to be extra careful regarding throttle for traction, also felt like no difference at all between map 1 and 2 so I’m a bit confused if I like it or not for hard enduro… any tips ?

[@InsideEnduro]

Interesting! Personally I run my 300 on the low power mode - Matt. I can tell a big difference.

[@SmartCarbFuelSystems]

Hi Mauricio, have you tried leaning the clicker adjuster out a few clicks to soften the response a little bit? We tend to ship them a little rich which can make them more aggressive than some people prefer.

[@mrmauco]

@@SmartCarbFuelSystems I really appreciate your support… I think I found the culprit… I installed the Zero Resistance Throttle (ZRT) cam for ODI grips and I just learned that it is a quick turn cam design, so the bike is running so well that every throttle input was giving me too much of a response… I have since installed the ODI S cam (regular throttle travel) and find much more fine control for hard enduro and the bike runs so smooth and responds so well to throttle inputs that I might as well be on a completely different machine… wanted to share this data with you so you can continue providing such excellent customer service.

[@SmartCarbFuelSystems]

@@mrmauco thank you for sharing! Let us know if you need anything else, we're always happy to help.

[@scannorse]

@@SmartCarbFuelSystemsi just wanna have access to the SC in Europe …speaking as a dealer….contacted you guys, long response times, something about possible european setup by some scooter guy who dont respond well either

[@Adventuredriven]

Great video, Kande and I need these for our 300 Beta's thats for sure, have to add it to the list. BTW we are your neighbor with the army truck :)

[@sublime929]

Does the smart carb come in a size shmedium like that shirt?

[@InsideEnduro]

James wears XL or XXL. I wear a medium hehehe - Matt

[@chrisvozza6530]

I have a lectron that works similar to this smart carb on my yz and yea it keeps gas in the tank way better then my stock carb but I did sacrifice some low end torque

[@InsideEnduro]

We have not had the best experiences with Lectron

[@chrisvozza6530]

@@InsideEnduro what were those experiences with the lectron?

[@SmartCarbFuelSystems]

The SmartCarb has a variable throttle rate venturi (non-round) designed to keep a stronger signal at the metering rod down low (0-1/4 throttle). Makes for a more crisp, strong off-idle response.

[@chrisvozza6530]

@@SmartCarbFuelSystems dam I shoulda went with the smart carb cuz my lectron sux off idle. I'm thinking of slapping my stock carb back on. Thanks for the info keep those vids coming

[@dennismillus4581]

How about the Smartcarb vs the Keihin Stic?

[@tomschaerer7515]

The smart carb has NO jets and automatically adjusts its self for altitude and temp. Real cool. Would be excellent for ultralights

[@SmartCarbFuelSystems]

Exactly, which is why we're seeing a huge increase in interest from the paramotor market (Polini Thor & Vittorazi Moster owners primarily).

[@victordavies8285]

Do they have a 42m and canyou put 4 together.to work on a 4stroke.

[@InsideEnduro]

Smart Carb has carbs for almost every bike!

[@SpeedySpears]

Digging the stache! I think Matt needs to grow one to match 😉

[@InsideEnduro]

lol...some day

[@henryhawk978]

Know it's past but a very beautiful deal. Enjoyed the vid.

[@InsideEnduro]

Thanks for watching!

[@PNW_MX222]

Wish someone would fine tune each carb and dyno them for these videos. And Cody Webb doesn’t want more power, he even says he wants smooth torquey low to mid power and that’s why he runs the SC2.

[@SmartCarbFuelSystems]

We've already done that: smartcarb.com/wp-content/uploads/2024/04/AVG-SC2-VS-Keihin-New-Rod-Design.jpg 7 test averages performed same-day. Keihin tune confirmed for ambient conditions by Webb's former mechanic Cody Richelderfer. Smooth, torquey, AND more low to mid power doesn't come at the expense of any less on top. There are no downsides. That the SmartCarb outperforms the Keihin, dialed, on the top end wasn't in question. Our land speed records, youth MX champion racers, snowbikers (BRC endorsed), and more attest to that. Our latest tuning developments in metering rod fuel profiles based on Cody's feedback focused in on that low to mid range and the D-F series metering rods that came out of that process are what Cody and other top hard enduro racers compete with today including the other 3 top finishers at last Sunday's Moab Hard Enduro - not to mention Alfredo Gomez with Rieju.

[@properpools]

Would love to see a 2022 Sherco vs 2022 beta video!

[@InsideEnduro]

Great idea!!!

[@jamesself435]

Just ordered my ticket!!

[@InsideEnduro]

Awesome!!!

[@wadeb7536]

What was the weight difference between those two carbs with all hoses attached??

[@SmartCarbFuelSystems]

The SC2 is about 50% heavier, but it more than pulls its own weight 😉

[@erikeggenbakstad]

Nice, now, make one for my XR650R and I'll get one 😊👍

[@InsideEnduro]

I think Smart Carb may....Not entirely sure tho.

[@erikeggenbakstad]

@@InsideEnduro I couldn't find it on their site though.. I can send them an email and ask, thanks!

[@Ozfreerider_adventures]

Can these carbs be ran on a 90 degree angle ? I’m trying to fit one on my scooter and it fouls on the big bore larger cylinder ? I can either space out manifold or spin it sideways if it will work ?

[@SmartCarbFuelSystems]

The SmartCarb SC2 can be tilted up to 30 degrees down-draft and up to 15 degrees side-to-side, but no further. In your case a manifold may be required for proper mounting.

[@jeradbennett5030]

Great video thank you 👍

[@TuhoeTaniwha]

is there no 4 Stroke option ?

[@joshuavanzuydam5044]

When are we getting your Romaniacs footage ?

[@InsideEnduro]

James was not wearing a GoPro for Romaniacs. I posted Ditrocks GoPro vids from my helmet - Matt

[@mazzo2225]

Keihin!!!!!!!!!!!!!!!!

[@chrisvids1820]

My Kx250 chugs fuel. Whats better for an old KX, SC or Lectron?

[@InsideEnduro]

Shoot! I have no experience with those bikes

[@SmartCarbFuelSystems]

We've equipped many KX250s over the years and have solid tuning baselines. Feel free to reach out anytime.

[@deandee8082]

need to make em reasonably priced for inline 4's. 800ish range, before the chynese do

[@InsideEnduro]

Would be killer

[@Strict30]

where you buy the carbs?

[@InsideEnduro]

insideenduro.com

[@mlucasGrindstone]

But… would it work on a Vtwin… like the Yamaha Road Star 1700???

[@InsideEnduro]

Would need multiple carbs

[@mlucasGrindstone]

@@InsideEnduro it only has one carb

[@jonsainsbury8726]

"engine feels more electric" Meaning Jetting to lean...

[@SmartCarbFuelSystems]

Not true. SmartCarbs are a single circuit fuel system bottom to top. No multiple circuits signing on and off through the range. That's the electric feel - optimum fueling and atomization at every throttle position with no transitions, not lean running. SmartCarbs increase economy by improving combustion efficiency, meaning they put less fuel/oil unburnt charges out of the exhaust. That and they don't spill fuel. Haven't ridden anything that feels better you say. Well you should really try a SmartCarb sometime. They pair excellently with Apex heads. And don't lump the SC2 in with the Lectron, they're not the same thing.

[@dowboykfx470]

Can this run on a KFx 400

[@InsideEnduro]

I am not sure. Check with Smart Carb

[@onestripevert]

Are these made for 4 strokes too?

[@InsideEnduro]

I am not sure about that.

[@SmartCarbFuelSystems]

@@InsideEnduro it depends on the 4-stroke and the fitment challenges it provides whether or not we can equip them with our current top-pull throttled SC2 models. Kits are in heavy development and we'll have more information about 4-stroke kits in the coming months.

[@robertbaker9329]

What happens if the floats ever stick? It just dumps fuel into the engine?

[@InsideEnduro]

yes!

[@robertbaker9329]

@@InsideEnduro well crap oh well your videos have convinced me to buy one for my yz250x

[@SmartCarbFuelSystems]

@@robertbaker9329, if the floats stick causing a loss of float control, check-valves in the internal vent passages prevent fuel flow out of them and into the venturi but fuel may still flow past the metering rod (main and only circuit). At idle position that opening is very small and any fuel flow is highly restricted. The vent passage check-valves are intended only for short-term or tip over protection. We recommend keeping the fuel turned off at the tank petcock unless actively riding the bike (turn it off in the pits, if laying it down to clean it, during transportation or overnight storage, etc). Every SC2 ships with an in-line fuel filter included to keep the fuel free and clear of debris entering the SC2. Keep the fuel clean, keep it off while not riding, clean the carb annually, and replace service parts including the float needle seat & o-ring every 2-3 years and you're set.

[@robertbaker9329]

@@SmartCarbFuelSystems ok that all makes sense just turn off the fuel and you won’t have a problem but I ended up ordering a smartcarb from you last Tuesday I’m hoping it ships soon I’m pretty excited I ordered a black one so I’m not sure if there made to order or not but the wait is killing me but I’ve also noticed how often you guys reply to people on KZbin and that’s amazing I never see a company reaching out to people directly like this you guys are seriously awesome I really do appreciate it

[@1991enduro]

I got a xr250r old school carb is a bitch honestly had so many problems tuning it thay do make a carb for my bike would my problems go away with this as it's a pricey but of kit

[@InsideEnduro]

Maybe, I have never ridden an XR250r with a smart carb installed.

[@my2cents395]

You may not think of this but with better fuel economy you can run less fuel to save weight.

[@SmartCarbFuelSystems]

Absolutely. The SC2 gives about the same range increase as the typical IMS oversized tank does, only without the added weight, higher center of gravity, and fuel cost savings. Another way to look at it is to do what Cody Webb did at round 1 of the 2024 US Hard Enduro Series at King of the Motos in January. The fuel economy gains the SmartCarb gave him allowed him to skip the final fuel stop headed into the last lap, giving him the advantage of breaking away from fuel injected KTM/Husqvarna racers Trystan Hart and Ryder LeBlond to take the win.

[@vanzaitv2775]

Can i buy smart carb. From you?

[@InsideEnduro]

Yes! Head to insideenduro.com

[@jonsainsbury8726]

YZ250x Apex SX Head and Apex Keihin jetting chart Haven't ridden anything that feels better .. Lectron/SC2....no thanks

[@richardcranium5393]

You could keep the 1000 dollar carb.

[@InsideEnduro]

Happily!!!

[@marty_on_30s]

Spooge

[@InsideEnduro]

messy

[@neelsuys4181]

Unfortunately there is a lot of misinformation in this video. Apart from the obvious, this dude needs to learn his terminology. Not a rant but know what you are talking about when doing a video like this.

[@cd1168]

Not a very informative video. Mpg and made in USA ? This guy has no business making a performance video without verifiable facts such as performance charts Reminds me of a snake oil salesman

[@InsideEnduro]

I run the stock carb on my 2 strokes for now - Matt But...I have quite a bit of experience with the smart carbs and they are legit. I still run the stock carb because I am always perfecting our jetting for customers that buy new 2 strokes from us.

[@mazzo2225]

Keihin!!!!!!!!!!!!!!!!