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.
- 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.
@@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!
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 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.
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
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.
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.
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.
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.
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.
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.
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.
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.
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😂
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