That hose connection on the bottom isn't a vent, it's JUST a bowl drain. Unless you open the drain screw, nothing will ever come out of that hose. The carb is entirely internally vented.
@@SmartCarbFuelSystems lmao, yeah.. After finally getting a gorgeous 2smoke 250 husqvarna and realizing its scary as f, I couldnt yet imagine cranking on a 300 WOT! I grew up on bikes and had fast stuff as a teen (89 yz 125). I hadnt had a bike for over a decade though and nice bikes were out of reach. I ended up going from a klx140 with 17/14 to a 2013 WR250 thats lightly built! Its lovely but taking some getting used to. I thought it was hillarious when kyle said "you cant" and snickered, we all knew what he was thinking!
- Really nice review! I'm using the SC2 36mm for my KTM EXC 300 2017 and I didn't have to touch the airbox boot (also asked the SC support if I should). - Regarding the adjusting rod dial - it's leaning or reaching the mixture only for the low-to-mid portion of the RPM and so even if you'll set it to a very lean setting when you'll WOT it you don't need to worry about the cylinder not getting enough lubrication (According to their support after I was a bit concerned about that). - It doesn't drop fuel because it's a closed system so the fuel that supposed to be dropped is actually returns to the bowl :)
I run supermoto I was worried about not being able to tune the top end like with the lectron I have I adjust the power jet for the top end. I literally sent smart carb a message today about this. . does the top end get enough fuel regardless of weather , altitude etc? .Also How does the top end feel (powerful, mushy and flat,) ?
@@SupermotoBuild That's the answer I got from the SC2 team back then when I asked them that: "The clicker only affects the bottom end, yes. The higher the throttle position the less the clicker has an effect and the fueling is more controlled by the selection or choice of metering rod. That being said, the clicker will affect the top end but only slightly. It affects the bottom end much more. Changing the top end fueling characteristics requires a change of metering rod. If you are still feeling that the top end is lean then I would suggest trying the step richer A-Q09 metering rod that shipped with your SmartCarb." Now, regarding the feeling on the top end - the bike feels very responsive and really wants to pull me away from the handlebars (I'm riding a 300 2T). I hope it helps.
One of the best tuning tests you can do is the fuel off and idle to off. There was a gentlemen who figured this all out and made a nice manual for the adjustment. A little searching and you can find it. Basically, If the bike surges as it runs out of fuel, it is too rich. If it just idles and then just dies, you are probably right on the money. I have this on my CR500 and it was awesome. I also have a Lectron on my KTM300. Both are great, both function as designed. The Smart carb is much easier to tune but it does cost a bit more.
This looks to me to be 1 of the best 2 stroke carbs to date especially for old timers that prefer carbs over TPI. The wheels in my head are turning and figuring when I can afford to buy one.
Interesting idea I learned when considering the hassle of carburetor tuning: Speed Density vs. MAF fuel injection tuning are two main fueling strategies for fuel injection. OEM calibration of Speed Density always takes more hours and effort to refine compared to MAF tuning, however it has proven reliability, the AK47 of fuel injection.
I for one.. can not wait for the Lectron vs Smartcarb review!! was a difficult decision when I went with my Lectron. I just went with the lectron from there stronger history
I took the 38mm for my 2020 300RR RE. Bike is stupid lean with a huge bog in the mid no matter which direction I went (rich or lean). Went 17 clicks richer just to be able to ride at a decent pace. But even the top end is lacking compared to the stock carb. Then I had the throttle get stuck WO mid moto! They're sending me a richer needle, so I'm praying my $750 is not out the door!
Better would be to see if you can't find decent E-free fuel in your area. Right now it could be anywhere from 10 to 15% ethanol. Maybe even 20% depending on what they can get away with.
Fuel line inlet barb at the carburetor should be 90 degrees and able to swivel. This would tuck the fuel line in better and minimize it from getting snagged on something.
Something I’ve discovered, riding a gasgas mc250, with a smart carb 2, is after tip overs or dropping the bike, it doesn’t easily restart. I should say it’s more difficult to restart than with the oem Mikuni junk, and much more difficult than a Keihin….
Hard starting after a tip-over may be related to a slightly richer than ideal setting or a float level that's a bit too high. We've revised our standard float level lower over time. Please reach out to us direct with your serial number and we'd be happy to discuss your settings and perhaps lowering the float level 1-2mm.
Integrated, internal float bowl venting in the SmartCarb from the airbox right at the venturi bell-mouth communicates not only the same air density that the venturi sees but also its velocity (pressure). The result is maximum proportional air/fuel metering and it's the only way to properly implement a single-circuit, metering rod carburetor fuel system.
The reason for the price difference is because they're fully CNC machined, not castings from a tool made in the 70s and long-since paid for. Over time the price will come down, perhaps with castings or advanced plastics or simply volume.
Nathan Dyess I’m still riding my 38mm cast SmartCarb from the APT days. Would be nice to have a carb in that price range again. I believe it was $400 shipped to my door. $700 will certainly make me second guess it when I get a second bike.
Two things about this bother me: 1) For what a guy pays for a KTM......shouldn't the carburetion be perfect? 2) Why, for Pete's sake, did you not compare to a Lectron? There would never be a more perfect time or place!
I agree... When a rider forks out over 10 grand for a freaking dirt bike, you shouldn't have to put another $800 to $1200 or more into it just to get it to run the way it should anyway.
All these reviews etc on real new bikes. It's like going into any brand motorcycle shop, the parts dept is manned by 14 to 23 year olds that only know about a 1 to 3 year old bike, because that's what daddy bought for them. Has anyone tried one on an older bike? Lets go so far as to ask if anyone has tried one on a piston port bike, a vintage bike.? Sorry Kyle, not everyone rides brand new bikes.
It's just a shameless Lectron knockoff. So the same performance. They moved the choke to the correct side and stole the check-valve design from SmartCarb for their vent passages so I guess there's that.
That's correct. The blue hose at the bottom of the float bowl serves to direct fuel flow when draining the float bowl and it can also be used, via our drain hose float check method, to ballpark the float level externally without pulling anything apart.
This Beta is a Race Edition - not oil injected, so it doesn't need TPS. If it's not connected the light will come on but you can disable it by clipping the pink/purple wire per Beta's oi delete kit instructions. For oil injected Betas SmartCarbs are available with a TPS option.
Is this carburetor good for the winter because i installed a timbersled and i have to change jetting for shure but this carb could be make it much more simple. Thank for the video, very informative
Yes it is, though we recommend carb heating for snowbike applications. PST or Power Sports Tech out of Utah makes a clamp-on water jacket style heater specifically for our SC2 model SmartCarb. We can pre-tune specifically for your setup, taking into account engine mods, riding style, fuel selection/oil ratio, etc. Do not recommend the Timbersled filter. Reach out with any questions!
@@clementfortin4315 yes, no more jetting. No jets at all actually. Just a metering rod handling fueling through the throttle range. All adjustments are made externally, without tools, in seconds.
Because when you go high in elevation the air density decreases so you have less fuel pulled in the Venturi with the rod. I have a Lectron in my Husqvarna TE 2014 but instead of upgrading it to a Smartcarb would rather buy a TPI, have to save some $$$
@@rogermty1971bad choice. I'd take a smart carbs bombproof reliability and tunability over a tpi which WILL leave you stranded as soon as the battery dies on you, no kicking, no bumping, soon as voltage drops below the efi's needs you aren't getting ANY fuel. Fuck that, i dont trust being in the middle of nowhere on something that i cant even kick or bump if something goes wrong with the battery charging system.. accident waiting to happen.
@@MDM1992 I did replace my Lectron by a SmartCarb in my Husky 2014 and it ran great for year and a half. Then I replaced my Husky by a KTM 300 XC-W with TPI and installed an optional kick start kit. The TPI is smother and more repeatable than the SmartCarb, but not by much. This carburetor is the closest thing to a EFI you can buy, it is very good. Plus it is a mechanical device so it is not very complex. You can adjust it on the trail without tools! The only thing that worries my with the TPI machine is the oil injection, feel it can fail at any time and I won´t even notice.
Ffs 700 for a carb🙈most I ever paid was 20 euro for a old pitbike😂..never needed changing any on me mx bikes but 700 man.😂..hope yr wife doesn't watch this😂
He literally says he had stock, lectron, and Smart Carb on the bike. Also he said that the reason for switching is for different elevations when riding.
Why fuck around jetting when you can afford to try out something as great as this? Especially for a trail bike, i'd argue for racing a well tuned carb will probably be able to slightly edge it on power, barely though and thats assuming you can get the jetting absolutely perfect, its simple, and reliable in all conditions.. thats worth every penny in my opinion.
As far as I know, SmartCarb only makes carbs for 2 strokes while Lectron makes for four stroke as well. I have a Lectron carb in my Husqvarna TE 250 and it works ok, but would buy an Smartcarb too if had to buy another carb. But right now in my wish list TPI in on top, just need to save more cash.
After riding only on a motocross track for the past few months, I see no fun in woods and trail. You guys are really missing out. I find it much less dangerous riding in a controlled environment and rewarding after many laps you start to get the track. Just take it slowly if your ego will allow
it takes like 10 kicks to start my 2004 Cr 250 , i have the smart carb in mine , i feel like it floods by itself , i simply turn the gas on , turn the choke on and kick it . I had to bump start it the other night to get it started . I run my bike 32:1 mix .
You’re the only SC video I could find that actually explains the “click” metering rod adjustments and shows it. Thx for that! 🗽
That hose connection on the bottom isn't a vent, it's JUST a bowl drain. Unless you open the drain screw, nothing will ever come out of that hose. The carb is entirely internally vented.
Thanks for the correction.
being able to make rich or lean adjustments on the fly on a carby is next level !!!
Kyle says you cant adjust the carb wide open on the fly and chuckles... Challenge accepted!
@@SmartCarbFuelSystems lmao, yeah.. After finally getting a gorgeous 2smoke 250 husqvarna and realizing its scary as f, I couldnt yet imagine cranking on a 300 WOT! I grew up on bikes and had fast stuff as a teen (89 yz 125). I hadnt had a bike for over a decade though and nice bikes were out of reach. I ended up going from a klx140 with 17/14 to a 2013 WR250 thats lightly built! Its lovely but taking some getting used to. I thought it was hillarious when kyle said "you cant" and snickered, we all knew what he was thinking!
- Really nice review! I'm using the SC2 36mm for my KTM EXC 300 2017 and I didn't have to touch the airbox boot (also asked the SC support if I should).
- Regarding the adjusting rod dial - it's leaning or reaching the mixture only for the low-to-mid portion of the RPM and so even if you'll set it to a very lean setting when you'll WOT it you don't need to worry about the cylinder not getting enough lubrication (According to their support after I was a bit concerned about that).
- It doesn't drop fuel because it's a closed system so the fuel that supposed to be dropped is actually returns to the bowl :)
How much miles with a full tank did you do with the stock carburator and how much with the SC2?
I run supermoto I was worried about not being able to tune the top end like with the lectron I have I adjust the power jet for the top end. I literally sent smart carb a message today about this.
.
does the top end get enough fuel regardless of weather , altitude etc?
.Also How does the top end feel (powerful, mushy and flat,) ?
@@SupermotoBuild That's the answer I got from the SC2 team back then when I asked them that:
"The clicker only affects the bottom end, yes. The higher the throttle position the less the clicker has an effect and the fueling is more controlled by the selection or choice of metering rod. That being said, the clicker will affect the top end but only slightly. It affects the bottom end much more.
Changing the top end fueling characteristics requires a change of metering rod. If you are still feeling that the top end is lean then I would suggest trying the step richer A-Q09 metering rod that shipped with your SmartCarb."
Now, regarding the feeling on the top end - the bike feels very responsive and really wants to pull me away from the handlebars (I'm riding a 300 2T).
I hope it helps.
Thank you for your reply I think I’m going to buy one in a minute 😆
@@NirHason this helps big time thank you 🙏
One of the best tuning tests you can do is the fuel off and idle to off. There was a gentlemen who figured this all out and made a nice manual for the adjustment. A little searching and you can find it. Basically, If the bike surges as it runs out of fuel, it is too rich. If it just idles and then just dies, you are probably right on the money. I have this on my CR500 and it was awesome. I also have a Lectron on my KTM300. Both are great, both function as designed. The Smart carb is much easier to tune but it does cost a bit more.
Can you please share a link to this manual?
@@chris3407 specifically for these carbs? If it’s a general test, then I would think it would just help dial in the the pilot jet and air screw.
Can't wait to get a bike let alone a new carb, anyway love your vids very informative!✌️
This looks to me to be 1 of the best 2 stroke carbs to date especially for old timers that prefer carbs over TPI. The wheels in my head are turning and figuring when I can afford to buy one.
Smart carb is the best mod you can do to a non TPI bike..
@@mixalis6168id take a smart carb over tpi ANY day of the week.
Interesting idea I learned when considering the hassle of carburetor tuning: Speed Density vs. MAF fuel injection tuning are two main fueling strategies for fuel injection. OEM calibration of Speed Density always takes more hours and effort to refine compared to MAF tuning, however it has proven reliability, the AK47 of fuel injection.
SmartCarb is great since it’s compatible with Beta’s oil injection. Not so for Lectron...
That’s what made the decision for me
thanks for that it changes my opinion
IMO oil in injection on dirt bikes sucks. Just another pointless possible failure point.
3:00 - the packing was nice? I should think so for $700 ... 😅
I for one.. can not wait for the Lectron vs Smartcarb review!! was a difficult decision when I went with my Lectron. I just went with the lectron from there stronger history
Smart Carb is way, way better in my opinion, i have had both
Amazing! I wish they still sell the smaller 25mm ones.
@@SmartCarbFuelSystems Awesome!
Running the Lectron on my KTM 300 XC. Very very happy with it.
Kyle, a carb comparison would have been very helpful. Especially since you ran all 3 on the same bike.
I took the 38mm for my 2020 300RR RE. Bike is stupid lean with a huge bog in the mid no matter which direction I went (rich or lean). Went 17 clicks richer just to be able to ride at a decent pace. But even the top end is lacking compared to the stock carb. Then I had the throttle get stuck WO mid moto! They're sending me a richer needle, so I'm praying my $750 is not out the door!
Better would be to see if you can't find decent E-free fuel in your area. Right now it could be anywhere from 10 to 15% ethanol. Maybe even 20% depending on what they can get away with.
The one vent line is just to drain float bowel..
No, Smartcarb sprays much finer drops, which gives clear savings in every way. Try measure on a road.
I have noticed used smart carbs and Lectrons for sale on Ebay.
Fuel line inlet barb at the carburetor should be 90 degrees and able to swivel. This would tuck the fuel line in better and minimize it from getting snagged on something.
nice video kyle
Your the bomb dude. Thanks
Something I’ve discovered, riding a gasgas mc250, with a smart carb 2, is after tip overs or dropping the bike, it doesn’t easily restart. I should say it’s more difficult to restart than with the oem Mikuni junk, and much more difficult than a Keihin….
Hard starting after a tip-over may be related to a slightly richer than ideal setting or a float level that's a bit too high. We've revised our standard float level lower over time. Please reach out to us direct with your serial number and we'd be happy to discuss your settings and perhaps lowering the float level 1-2mm.
With the vent in the airbox you are aways getting filtered air into the engine.
Integrated, internal float bowl venting in the SmartCarb from the airbox right at the venturi bell-mouth communicates not only the same air density that the venturi sees but also its velocity (pressure). The result is maximum proportional air/fuel metering and it's the only way to properly implement a single-circuit, metering rod carburetor fuel system.
Love your channel!!
Wow I may need to buy one of these smart carb 2's for my older 2011 ktm 300 xc.
Thats not old
Fair review just plain to hard to beat EFI!
Carb is better
Old school carb is best
Brotherson seems like a cool name to have.
Would love to get an SC2 for my 4T, but just can't justify the cost. Can't wait till some good knockoffs are made 😂
No such thing as a good knockoff, Phil.
Love your videos!
Cool!
Did you notice any difference in power delivery between stock, lectron, and smartcarb? Would be nice to know if there were any subtle differences
love the videos
Still Don't quite consider the price to be fair compared to a Lectron features. If they go down I would buy one
The reason for the price difference is because they're fully CNC machined, not castings from a tool made in the 70s and long-since paid for. Over time the price will come down, perhaps with castings or advanced plastics or simply volume.
Nathan Dyess I’m still riding my 38mm cast SmartCarb from the APT days. Would be nice to have a carb in that price range again. I believe it was $400 shipped to my door. $700 will certainly make me second guess it when I get a second bike.
Smartcarb 41mm 2 stroke 👹 buh dekat rxz emy 👹💥
The carb comes set a little rich from the manufacturer.
Two things about this bother me: 1) For what a guy pays for a KTM......shouldn't the carburetion be perfect? 2) Why, for Pete's sake, did you not compare to a Lectron? There would never be a more perfect time or place!
I agree...
When a rider forks out over 10 grand for a freaking dirt bike, you shouldn't have to put another $800 to $1200 or more into it just to get it to run the way it should anyway.
Is that 2stroke carb sir? Can i fit it in a 4 stroke motorcycle?
what 3 bikes are ya gonna test this time
What size of fuel line did you need to use on that!! I have bern told 2 things! 1/4 inside or a 1/4 inch outside!! I have a 22 125x.?
A bit late on this but it's 1/4" inside diameter tubing or same as the stock fuel line for most of these bikes.
@@SmartCarbFuelSystems already got it..thank you you got back to me on a email I sent ya!! Thank you!!
Great
Very curious how you think it compares to a lectron
700 doller is a bike round here
It’s not a vent hose it’s a drain hose
All these reviews etc on real new bikes. It's like going into any brand motorcycle shop, the parts dept is manned by 14 to 23 year olds that only know about a 1 to 3 year old bike, because that's what daddy bought for them. Has anyone tried one on an older bike? Lets go so far as to ask if anyone has tried one on a piston port bike, a vintage bike.? Sorry Kyle, not everyone rides brand new bikes.
Planning on getting one for a ‘93. Did you try one on an older bike? How did it go?
Hey Kyle, please do XTNG Carb review? :)
It's just a shameless Lectron knockoff. So the same performance. They moved the choke to the correct side and stole the check-valve design from SmartCarb for their vent passages so I guess there's that.
sir have chance you sale that carb even 2nd hand?
So what carb do you like better the lectron or smart carb and if you were to buy more what one would you get
I’d really really love to win a bike!
Vent hose? Isn't it supposed to be a drain for the bowl?
That's correct. The blue hose at the bottom of the float bowl serves to direct fuel flow when draining the float bowl and it can also be used, via our drain hose float check method, to ballpark the float level externally without pulling anything apart.
Do they have these for ATVs?
Do you have any links for UK sites ?
how to order.? and how mach?
What did you do with TPS sensor and check engine because of diconected that plug?
This Beta is a Race Edition - not oil injected, so it doesn't need TPS. If it's not connected the light will come on but you can disable it by clipping the pink/purple wire per Beta's oi delete kit instructions. For oil injected Betas SmartCarbs are available with a TPS option.
Is this carburetor good for the winter because i installed a timbersled and i have to change jetting for shure but this carb could be make it much more simple. Thank for the video, very informative
Yes it is, though we recommend carb heating for snowbike applications. PST or Power Sports Tech out of Utah makes a clamp-on water jacket style heater specifically for our SC2 model SmartCarb. We can pre-tune specifically for your setup, taking into account engine mods, riding style, fuel selection/oil ratio, etc. Do not recommend the Timbersled filter. Reach out with any questions!
@@SmartCarbFuelSystems So your saying if a buy the carb i dont have to change jetting? Thanks
@@clementfortin4315 yes, no more jetting. No jets at all actually. Just a metering rod handling fueling through the throttle range. All adjustments are made externally, without tools, in seconds.
Khein tutta la vita...
I have a 96 KX 250. Anybody fitted a Smart Carb to this bike?
We've equipped over 100 KX250s with the SC2 SmartCarb, a few of which are '96s.
2022 ktm sx85 it comes with 38 keihin card if im buying smart carb should be same size?
The KTM 85 SX comes with a 28mm Keihin PWK. We recommend replacing size-for-size with our 28mm SC2 SmartCarb.
7:00 - how does it self meter for elevation changes?
Because when you go high in elevation the air density decreases so you have less fuel pulled in the Venturi with the rod. I have a Lectron in my Husqvarna TE 2014 but instead of upgrading it to a Smartcarb would rather buy a TPI, have to save some $$$
@@rogermty1971bad choice. I'd take a smart carbs bombproof reliability and tunability over a tpi which WILL leave you stranded as soon as the battery dies on you, no kicking, no bumping, soon as voltage drops below the efi's needs you aren't getting ANY fuel. Fuck that, i dont trust being in the middle of nowhere on something that i cant even kick or bump if something goes wrong with the battery charging system.. accident waiting to happen.
@@MDM1992 I did replace my Lectron by a SmartCarb in my Husky 2014 and it ran great for year and a half. Then I replaced my Husky by a KTM 300 XC-W with TPI and installed an optional kick start kit. The TPI is smother and more repeatable than the SmartCarb, but not by much. This carburetor is the closest thing to a EFI you can buy, it is very good. Plus it is a mechanical device so it is not very complex. You can adjust it on the trail without tools! The only thing that worries my with the TPI machine is the oil injection, feel it can fail at any time and I won´t even notice.
If only it were hundreds cheaper….
Ffs 700 for a carb🙈most I ever paid was 20 euro for a old pitbike😂..never needed changing any on me mx bikes but 700 man.😂..hope yr wife doesn't watch this😂
What was wrong with the stock carb that you felt the need to change it? Did you try a Lectron on this bike too?
He literally says he had stock, lectron, and Smart Carb on the bike. Also he said that the reason for switching is for different elevations when riding.
@@Zalagar619 You should to understand that 50% of people are stupid and ignorant...
Why fuck around jetting when you can afford to try out something as great as this? Especially for a trail bike, i'd argue for racing a well tuned carb will probably be able to slightly edge it on power, barely though and thats assuming you can get the jetting absolutely perfect, its simple, and reliable in all conditions.. thats worth every penny in my opinion.
I think these metered carbs are awesome but $600-$800 is a big old bucket of money. If competing maybe but for your average dirt-mamal, hmmmmm ...
Can i use this carb for 4 stroke motorcycle ? I wish it will work
As far as I know, SmartCarb only makes carbs for 2 strokes while Lectron makes for four stroke as well. I have a Lectron carb in my Husqvarna TE 250 and it works ok, but would buy an Smartcarb too if had to buy another carb. But right now in my wish list TPI in on top, just need to save more cash.
After riding only on a motocross track for the past few months, I see no fun in woods and trail. You guys are really missing out. I find it much less dangerous riding in a controlled environment and rewarding after many laps you start to get the track. Just take it slowly if your ego will allow
not everyone is as boring as you.
I though im watching ph at the beggining
it takes like 10 kicks to start my 2004 Cr 250 , i have the smart carb in mine , i feel like it floods by itself , i simply turn the gas on , turn the choke on and kick it . I had to bump start it the other night to get it started . I run my bike 32:1 mix .