Technology Elevated SmartCarb SC2 Review
Can the SmartCarb SC2 really increase the power and fuel economy as well as compensate for altitude and atmospheric conditions? We put it to the test to find out.
Photography by Handsome Rabbit
They say two-strokes are dead. But who’s they? With major OEMs like KTM, Husqvarna, Yamaha, Beta and Sherco still actively making some of our favorite premix-burning machines, it’s hard to say that two strokes are a dying breed. Technology Elevated (TE) is a company that is not listening to any of that noise and their SmartCarb is a carburetor-designed to breathe new life into any carburetor-equipped ride.
They claim a 10-percent increase in horsepower and 30-percent increase in fuel mileage versus standard carburetors. Perhaps more interesting, it compensates for ambient air density—altitude, temperature and humidity similar to electronic fuel injection (EFI). And like EFI systems, it is a closed loop with no vent hoses so it will not leak fuel. Also similar to EFI, there are no jets to change but it does include an external adjuster for fine tuning with no tools. We wanted to put this to the test in the real world, so we installed one on our 2020 Beta 300RR long-term test bike and used it at multiple locations over several months.
The Beta 300 RR is a very capable bike, which edged out the Husqvarna TE 300i fuel-injected two-stroke in our comparison test earlier this year. (You can read the 2020 Husqvarna TE 300i vs. 2020 Beta 300 RR Comparison here. The Beta comes standard with a 36mm Keihin PXK carburetor. And as we noted in that story, the engine performance is what helped it come out on top with most of our test riders. The Keihin does not really do anything wrong and runs great, so this gave us a great bike to test the claims for the SmartCarb.
For our initial test, we met the TE engineers at the MotoVentures rider training facility in Anza, California. The property sits about 3000 feet above sea level and features a variety of technical singletrack, moto jumps, rock sections and some wide-open sand washes. We eagerly jumped on the Beta in stock trim to get a good base setting for our back-to-back comparison before installing the SmartCarb.
After getting a good baseline, the TE crew helped us install the 36mm option for our carbureted Beta. The SmartCarb quickly replaces the OEM carb and accepts the stock throttle cable along with an optional connector for the throttle-position sensor, which is needed on the Beta due to the standard oil-injection system. We were feeling much smarter after some further education on the SmartCarb history during a quick 30-minute install. We were back out on the bike and ready to see if the SmartCarb could really outsmart these technical trails.
Each bike will have a recommended needle and you use the external adjuster that moves the needle up (richer) or down (leaner) for fine-tuning. From the first blip of the throttle, all our senses lit up with the improved responsiveness from the SmartCarb. We saw less smoke out the back, heard a crispier tone, and felt a stronger pull from down low. Like we said, the bike ran great with the standard Keihin but there was a noticeable improvement with the SmartCarb. The Beta felt torquier in the tight single track and was able to hop, jump, and skip over rocks with a quick twist of our right hand. Overall, this made it a lot easier to attack the tight stuff and gave us added confidence in the resilient power plant that could tow us around as we linked sections together. We did not have the opportunity to put the SmartCarb-equipped bike on the dyno to test the “10-percent increase in power” claim, but we were happy with the more important real-world performance we felt after multiple back-to-back comparisons over the next few months.
Equally as impressive, the SmartCarb ran exceptionally well at several different locations and altitudes. Once we used the external adjuster to get the setting set that first day, we did not feel the need to change it regardless of the changing altitude, temperature or weather conditions. The only complaint we had was that the Beta has a check-engine light that would come on sometimes and it took us a little while to realize it was not really causing any problems and the bike was running fine.
To test the claimed 30-percent increase in mileage, we did another back-to-back test and started with the SmartCarb back at the MotoVentures property. We set up a loop and with one gallon of fuel, rode laps until the bike came to a stop at 31.5 miles. We installed the Keihin, put a gallon in the tank and proceeded to do laps on the same loop. We had plenty of riding time to do some math in our head and figured that if the claim was correct, we would run out at around 22 miles. While the bike did keep running past 22 miles, we could see that the tank was about dry and it stopped at 24.7 miles, about 28-percent less distance. Not quite the claimed 30-percent increase but still significant. Extrapolating that to the 2.55-gallon tank, the SmartCarb will go about 80 miles while the stock Keihin will run dry at around 63 miles. That is a long walk if it leaves you that far from your truck or a big difference in pit-stop strategy for racing.
The Keihin line of carburetors have been refined for several years and, in our experience, superior to the Mikuni carburetors. So it is impressive that the SmartCarb can provide a lot of benefits over that proven product. To achieve better performance on the trail, (nearly) 30-percent increase in mileage, virtually eliminate the need for tuning for atmospheric conditions and provide a tool-free method for any necessary fine tuning makes this a great product. We only tested the SmartCarb on a 2020 Beta 300 RR but based on this experience, we feel that it would have similar results on any carbureted two-stroke, especially the last couple of years of KTMs that came with a Mikuni carburetor. We know that Cody Webb has chosen to use a SmartCarb on his factory-backed Sherco after testing it against the Keihin and Lectron. The suggested retail for the SmartCarb SC2 is $699 to $774 depending on your application.
Check out our video review here:
SmartCarb vs. Lectron: What’s The Difference?
For this report, we tested the SmartCarb against the stock Keihin so we cannot say how it compares to the Lectron in action. If you do some research, you will find that the Lectron carburetor uses some similar technology, so people often ask how they compare. Both carbs use metering rods in lieu of jets and needles, and both manufacturers make similar claims in terms of performance, air density compensation, and ease of use. Interestingly, they were both designed by the same person. SmartCarb has an article on their website that explains the history of both carburetors and the differences in design, so we pulled highlights from that. You can read the complete article HERE.
The late William “Red” Edmonston invented the Lectron carburetor after he first pioneered the metering rod carburetor concept with the Posa-Fuel and Lake Injector in 1967 and 1971, respectively. The Lectron came to market in 1974. Red sold Lectron to General Motors in 1978, and he continued to work on an evolution of that original design, and the SmartCarb came out in the early 2000s. Technology Elevated’s Chief Technology Officer and Founder Corey Dyess had the privilege of working with Red during his final years and has led advanced development of the SmartCarb, winning multiple patents for feature improvements over time.
While the Lectron and SmartCarb share some design elements, there are several differences. Below are some of those differences:
- The Lectron uses a traditional round bore, while the SmartCarb uses a patented “inverted egg” venturi shape to improve the velocity and fuel pickup.
- The SmartCarb uses no float-bowl venting. It instead uses a “scoop/port” inside the venture to vent the carburetor, and this is how it compensates for atmospheric conditions. More air means more fuel pickup and vice versa. The Lectron still requires tuning of the power jet to compensate for elevation and large changes in temperature. The SmartCarb has just one external adjuster for fine tuning and an idle screw.
- The SmartCarb is a little easier to interchange with the stock Keihin and Mikuni carburetors. It uses the stock throttle cable and is the same end-to-end length, while the Lectron is 6mm longer and requires a different cable. The Lectron also does not offer a throttle position sensor (TPS), which is necessary for many bikes, including the Beta we used for testing.
- Because it has no external venting, the SmartCarb releases less evaporative emissions and will not leak fuel if the bike tips at an odd angle (this partially contributes to the improved fuel mileage).CN