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Smart carb/Lectron carb

woodsguy

Ride Red
Joined
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Location
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First Name
Rob
Last Name
Vaughan
Anyone using these on 2 stroke dirt bike, if so:
1-happy with it over a carb
2-Which brand and why
3-how hard to setup
 
I think sander has one on his 2 stroke 300
I believe he had issues with the 300 but I think it was with the suspension

According to tech info, my key takeaways (beside that cool transparent float bowel):
The shape of the metering needle in itself is a fuel signal-generating device. The flat side of the needle in a High Velocity Chamber, enhances the fuel pick up signal. The metering rod accomplishes this by creating divergence. This divergence is similar to the low-pressure area created by an air craft wing, which utilizes low pressure to create lift. The Lectron carburetor uses divergence to create “Fuel-Lift”.
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Both air temperature and elevation affect airflow volume by weight. As temperatures decrease air becomes more dense and heavier. The denser, heavier air will pick up more fuel when passing the metering rod due to the signal generated at the rod and the shape of the rod. Conversely, as elevation increases less dense or thinner, the lighter air will automatically pick up less fuel by weight while still maintaining the optimum air/fuel ratio.
 
I thought about mounting one on my 530 EXC so I could avoid messing with rejetting. I just never got around to it. In the process though, I did read a lot of positive reviews. I don't recall seeing many negative reviews. I think the company is somewhere over on the North side of San Antonio. If you were serious about one, it might be worth a road trip to see them.
 
i have a buddy who likes his smart carb so much, that he put it on both his '14 200 & '15 250 xc-w, and also on his wife's freeride 250, and on his daughter's 105-xc.
and this guy loved to play around w/ jetting. he knows what good jetting is ....

there was another rider i met up in ARK who lead a bunch of us on a 500 mi. d/s loop.
With him leading, he'd routinely hold a steady 70 mph on pavement 10-20 mins at a time, leaving all of us behind! wow. I didn't think a two stroke dirtbike could go that fast on pavement. after Seeing it, i'm a believing it.
i think he said his '17 300 xcw got a Lectron,not 100% certain. My jaws dropped when he said w/ his new carb, his mpg went up +10 to an astonishing 45 mpg - on a two stroke!

imo, if i were to upgrade to a late model 2 stroke dirtbike that's not a TPI, I'd drop the coin for one of these set- it- and- forget- it carbs.
but since my smoker's a relic, i'm letting the dinosaur carb get er done.
 
I've got one (Lectron) on my 17 300 Six Days and it's really nice. Put it on to ride Colorado and never looked back. It does take some fiddling with the metering rod to get it perfect.
Comes set-up for your bike, you just fine tune. Install was a breeze.
I've heard the Smart Carb is better but never tried it. Gas milage was a little better but Nothing like my TPI 300. If you're around the area feel free to take the bike for a spin.
I'll be heading to Galveston late March if you want to meet up somewhere and check it out.
 
The guy who bought my CR500AFC installed a Technology Elevated Smart Carb and he said it was simple to tune. He also mentioned it made a big improvement over the stock carb throughout the rpm range. Keep in mind, this is what I was told; I don't have any personal experience with them.
 
I thought about putting one on the DR650 to help with the decel pop but at the end of the day I never ride it and if someone wants to buy it they can chase that demon for me. I will live vicariously through their efforts.
 
I've got one (Lectron) on my 17 300 Six Days and it's really nice. Put it on to ride Colorado and never looked back. It does take some fiddling with the metering rod to get it perfect.
Comes set-up for your bike, you just fine tune. Install was a breeze.
I've heard the Smart Carb is better but never tried it. Gas milage was a little better but Nothing like my TPI 300. If you're around the area feel free to take the bike for a spin.
I'll be heading to Galveston late March if you want to meet up somewhere and check it out.
I'm chasing demons on my 250 sx, just wondering if this will solve them. Just can't get it to stop fouling plugs. Much better than when I got it, but it still does it.
 
I kinda miss my 86 Husky 250 XC Smoker , had a ICO on it and there were many times after a days ride I would check peek speed for the day and it would be 99.9 . That’s as high as it would go . It had the first flat slide Mikuni on it , I did install the ideal screw set up as soon as it came available . Been thinking about that Lectron for my Beta but the carb on there has preformed excellent from sea leval to 11,000 ft with no tinkering , mileage is erratic , that’s my only issue with it I have a small tank and it has varied as much as 30 miles in the same altitude riding , last year I bought a tank full of non e gas and mileage was some of the lowest I’ve had . That’s a 15 gallon tank so it’s not just for one ride . I carry my dirt bike gas in a support tank so I have never filled it from store pumps . And it always gets treated gas so it has never had ethanol issues .
 
I'm chasing demons on my 250 sx, just wondering if this will solve them. Just can't get it to stop fouling plugs. Much better than when I got it, but it still does it.
My 17 300 had KTM changing carbs from the previous year. I had the bike about as good as I could get it and still wasn't right. Most people said to go back to the previous year carb. I went with Lectron. I did need to adjust the metering rod to get it near perfect but it's an easy adjustment. What oil/ratio you running? KTM said for me to run 60:1. I hesitated but it seems to work. I do run race gas and Motul 2 smoke oil.
 
60:1, Motorex. I've had "real" mechanic check out with leak down and compression tests. All good, did not check stator?? Seems to be jetting issue. I went with JD and his suggestions, I'm thinking since its a sx, he's rich for mx. i use for woods, go try going leaner... I'm just not a carb guy. Love the darn bike. Runs fine, just eventually going to foul a plug.
 
I lugged my 2013 250sx around in 3rd gear through the national forest for a couple hundred hours and never have I fould a plug. Stock jetting and I run 40.1 with an fmf forest legal silencer. I had another 250sx that I installed the 300 kit on that Terry Cunningham had later bought from me. It never fould a plug either if I remember right. Is there any chance maybe your air filter is over oiled maybe?
 
What color is the plug? Do you have a lot of spooge out the end of silencer?
Main Jet
Piiot Jet
Needle
Have you set the float level
What power valve spring are you using? Red, Green, yellow?
 
Black
yes to spooge
165
40
needle that JD kit suggested, not sure
no to float
no idea on spring but that shouldn't foul a plug

And I too have had numerous sx without issue. I didn't but this new although very low hours, but still don't know history
My riding buddy blames it in being made or sx but as you and I stated, been there done that without problem.
 
Your plug is really the part that gives you the answers. The power valve spring tells the engine when its going to hit the power band. Are you a lugger or torque guy or an on the pipe guy? Your bike is meant to be on that pipe. If you could get on the bike and scream it wide open then cut it off and look at the plug it will tell you if it's the main jet. Maybe a process of elimination. A lot of people are using a Suzuki needle on your bike. Back in the day we used to say it is 1/3 pilot jet 2/3 needle jet and 3/3 main. That isn't exact science. .I never got my 17 to run right with the JD kit, Going to Colorado forced me to get the Lectron and it's still on. You might put in a call to Chip Munn of Munn Racing KTM. He used to be a big KTM 2 stroke guy and is super nice. He's always been known for helping the local privateer.
 
Thanks for the reply, obviously at 67 y/o in the woods the bike isn't on the pipe a lot. That said, neither were my other sx's. I understand it's meant to run, but the bike can run like I ride it if all is working correct, something isn't. I usually run right off pipe and just as it hits and shift. Of course occasionally it gets to run. Seems fine when running, shut off for a break and when head back out it'll go a 100 yards or so and poof!
 
Don't know much about your KTM but assume it has Reed. I would check the valve. Sounds like the case is loading and on restart too rich. Does that make sense to anybody but me?
 
Reeds were checked by the mechanic, said they were good. :giveup:
 
So I was thinking about JQ1.0 question along with previous question about float level. I was wondering if float level is high or bike is parked in a way that allows fuel to overflow into the intake and pool in the reeds this could dump a load of fuel on restart causing the fouling.
 
Rob , I'm assuming your 250sx has a keihin 36mm PWK?
 
Reviving an old thread... as I have an issue.
I have a 2019 150 xcw, last year of the carbureted bikes. I swapped the stock Mikuni for a smartcarb sc2 after 6-7 hours.
the bike has been running beautifully the first 10 hours or so with the sc2, mostly national forest and one TORCS race. However, this past weekend was a different story. I rode the forest Saturday and Sunday. Saturday, fouled a plug after 45 minutes, swapped it for a new one, ran perfectly the rest of the day. Sunday morning, would start, checked the plug, and it was wet. Put yet another plug in, ran great for about 3 hours, then died on me a couple of miles from the end. Plug was wet as well. Had to get “towed” by a friend back to the trailhead parking.
This is very frustrating to me, 3 fouled plugs in roughly 5 hours or riding, but no issues the previous 10 with sc2 and 6-7 with Mikuni. Any thoughts?
 
I love my Lectron, it was true bolt on and go. On a 2008 KTM 300 XC. The Smart carb wasn't available when I was in the market.

I ride in the mountains each summer with 4-6k elevation change, the Lectron is like mechanical FI.
 
Reviving an old thread... as I have an issue.
I have a 2019 150 xcw, last year of the carbureted bikes. I swapped the stock Mikuni for a smartcarb sc2 after 6-7 hours.
the bike has been running beautifully the first 10 hours or so with the sc2, mostly national forest and one TORCS race. However, this past weekend was a different story. I rode the forest Saturday and Sunday. Saturday, fouled a plug after 45 minutes, swapped it for a new one, ran perfectly the rest of the day. Sunday morning, would start, checked the plug, and it was wet. Put yet another plug in, ran great for about 3 hours, then died on me a couple of miles from the end. Plug was wet as well. Had to get “towed” by a friend back to the trailhead parking.
This is very frustrating to me, 3 fouled plugs in roughly 5 hours or riding, but no issues the previous 10 with sc2 and 6-7 with Mikuni. Any thoughts?
You said the plug was wet when you checked it. Other than that, what did it look like? Was it black with soot or clean and shiny?
 
You said the plug was wet when you checked it. Other than that, what did it look like? Was it black with soot or clean and shiny?
It was black. I’m clearly running way too rich, but may also have a 2-T oil over-saturation.... I’m running 50-1 mix, Motorex cross power 2T, and I may not be burning it off efficiently, as I do not run at high RPM often. Is it possible that I have too much excessive spooge collected in the exhaust packing, and it may have leaked back into the cylinder overnight?
 
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