Does anyone have any experience with these? They're gaining popularity in the modern dirt bike market.
It's more or less a modernized/improved Lectron. Very trick design.
https://technologyelevated.com/smartcarb-vs-lectron/ (https://technologyelevated.com/smartcarb-vs-lectron/)
(https://technologyelevated.com/wp-content/uploads/2020/01/SmartCarb_2.png)
Very interesting, pricey I imagine......................D
$700 each.
Yeah, a bit spendy.
Quote from: sav0r on July 26, 2020, 04:21:38 PM
$700 each.
Yeah, a bit spendy.
Definitely not cheap but I think that is in the ball park of a genuine FCR carb if it's the dirt bike market they are after.
ive heard people go on and on about those ad nauseum. I'd love to get my hands on one and really take a long look at one, see what the fuss is about. there has to be something about them, but? id find it real hard to justify spending 1400 on a set for a twin. or 700 for a single. Ive heard they are the shit for singles and racing but.. why? from the description, the bowl is pressurized by pulling a signal from the bellmouth from what looks like a CV carb type inlet, and compensating in that fashion, and then the fuel is discharged though a hollow needle? interesting for sure. this is -sort of- what the rd400's were trying to do with the air line to the airbox but a step further. worth the cost? dunno. Id hate to have a bad needle and seat though. hydrolock time. :eek:
I know the modern KTM and Husky guys love these, but for a 70's-80's 2T twin, even the top tuners agree the Keihin PWK is tough to beat.
If these are "a modernized Lectron" I can't imagine they wouldn't work very well. Now that I understand how to set up lectrons and I have mine working just about perfect I love them. They are perfect throughout the entire range. No flat or dead spots. The only thing I don't like about them is they seem to be a little more sensitive to temp changes than Mikunis. When it's hot and humid I can really feel a difference. But it still runs flawless. Just a little less angry when you twist the throttle. Buying lectrons one at a time are not cheap either, but I got a pretty good price for two. Maybe there's price break on these for more than one as well.
You run those on the street or on a race bike?
Quote from: sav0r on July 26, 2020, 09:20:09 PM
You run those on the street or on a race bike?
Street bike...........I have them on my TZ replica.
That's cool! My father and I talked about Lectrons on the GT750 race car, but for three of them it was a bit much at the time. A friend offered a free set to us (they are vintage Lectrons from the 70's so it would be a nice period set), but they are only 30mm (or so he says), which isn't even close for our needs. I've been trying to get them from him just to play with them on my RD, but they are lost in his never ending pit of a garage somewhere. Someday...
Smart carbs came out a few years ago to huge hype. The pre-sales dragged on and on and they kept delaying delivery. People kept going on about how great they were going to be. But when they actually started delivering them they turned out to be absolute garbage. The smartcarb website even shut down after a while. Now they have a new name and even more claims of greatness.
One thing they definitely did do was to increase sales of lectrons hugely.
i mean a pair of lectrons isn't that far off price wise from 1 smart carb, i looked yesterday at the banshee kits out of curiosity. also theres lots of hot H2s running lectrons on the street, they are proven. Ive had 2 sets, they were way to sensitive for my liking the bit i played with them.
I mean, i got a pair of tms new for 300 bucks. i doubt the smart carb is 2x as good as the lectrons or tms.. (price vs value).
Lectrons are tried and true. I see no reason to attempt reinventing the wheel.
Quote from: thatguy on July 27, 2020, 08:12:15 AM
Lectrons are tried and true. I see no reason to attempt reinventing the wheel.
They're not reinventing, just improving apparently.
There's a link in the original post explaining their carb vs Lectron.
The smartcarb was designed by the same guy who designed Lectron, Lake Injectors, etc.
I'd rather get a new set of PWK's from Partzilla for around $250.
Quote from: retaRD on July 27, 2020, 11:59:14 AM
Quote from: thatguy on July 27, 2020, 08:12:15 AM
Lectrons are tried and true. I see no reason to attempt reinventing the wheel.
They're not reinventing, just improving apparently.
There's a link in the original post explaining their carb vs Lectron.
The smartcarb was designed by the same guy who designed Lectron, Lake Injectors, etc.
This I knew. And stand by my statement.
http://www.buildagyrocopter.com/lake-injector-fuel-system/
Smart or lectron does nothing to make laminer air flow and linear power . A modified VM or PWK with venturi dividers and a intelajet is un beatable in performance . I have also installed venturi dividers in Lectrons . But adjustability with intelajet is awesome plus fuel is discharged atomized fro the nozzle
one moe pic
has anybody on here used a lake carb or a new smart carb at all, 1st hand experience?
Quote from: racerclam on July 29, 2020, 10:52:19 AM
plus fuel is discharged atomized fro the nozzle
Isn't that part of what makes Lectrons work so well is that they "atomize" or "vaporize" the fuel?
year sgo when chuck was still heavily involved in the watercraft racing, he showed me some pics of carbs they had made with 30? annular discharge nozzle ports around the carb. that was some seriously sexy stuff right there. Not sure if he'd share pics, and impracticable on a bike id think, but man. talk about 2 stroke carb porn.
Quote from: m in sc on July 29, 2020, 12:33:18 PM
year sgo when chuck was still heavily involved in the watercraft racing, he showed me some pics of carbs they had made with 30? annular discharge nozzle ports around the carb. that was some seriously sexy stuff right there. Not sure if he'd share pics, and impracticable on a bike id think, but man. talk about 2 stroke carb porn.
Yeah, that was pretty incredible. The overall design was pretty ingenious, too.
that was a good night for sure. :celebrate:
There are several variables at play with carbs. One is air flow and that includes all the varieties of UFO's and splitters which are all about smoothing out air flow through the carb body.
The other factor and one that is being discussed here, is fuel atomization. Fuel is not a vapor, it's liquid, but the liquid doesn't burn. What burns is the vapor on the surface of each duel droplet. For a given volume (or mass) of fuel, smaller droplets have more surface area than large ones, so breaking fuel into small droplets helps to create a faster and more complete burn.
That's why needle jets in a bleed design are often called emulsion tubes because the break the large flow into smaller droplets. One of the Japanese carb manufacturers recently introduced a new version of their flatslide carbs and they have a series of tiny holes in the needle to allow fuel to better atomize.
That's also why fuel injectors went from one single orifice to multiple holes for fines spray and smaller droplets.
The average piston ported two stroke has a needle jet with a tall spray tube to introduce air into the fuel spray and since a two stroke has a pretty violent inlet system in terms of pressure waves, the atomization process is typically adequate if not perfect.
A reed valve changes those pressure pulses and that's why we see bleed type needle jets in RDs. They improve atomization and reduce the amount of unburned fuel going out the pipe.
That carb design appears to bring more air into the bottom of the needle jet and then discharges fuel and air in smaller droplets through many discharge nozzles.
A flat slide significantly reduces turbulence compared to a round slide so they used that feature to improve air flow as well.
I would guess that Chuck's carb design was addressing the same droplet size issue.
I am not a big fan of air flow smoothing devices but they may reduce turbulence across the needle or idle jet outlet a little which might create a higher air flow across the jet which in turn would generate a greater pressure differential and would cause more fuel to flow at smaller throttle openings compared to s stock round slide as witnessed by the smaller pilot jets needed with those devices.
I'd like to see a comparison of fuel flow rates and torque in back to back dyno runs though to see the real world impact. I can see that a so called stronger signal should make the motor slightly more responsive. It won't neccessarily make any more power but if it responds faster it will feel that way.
A real improvement would be a twin injector set up with multiple orifices.
:good: speaking of two-stroke porn, that posting should have begun with: "Dear Penthouse..." Well written, I love this stuff!
Welcome to 2strokeworld where the customer always comes first...............
Years ago I was given one of these Tryton carbs. It wasn't very good, but the atomizing inlet reminds me of what was brought up before. You could turn the bell and depending on its position it was supposed offer different advantages.
(http://www.gear.ee/shop/image/cache/data/KM853-500x500.jpg)
http://www.gear.ee/shop/index.php?route=product/product&product_id=3216#.XyLCbsfQiCo
kind of. I wish chuck would post a pic, it was pretty amazing.
Just want to mention that venturi dividers are not air smoothers. But velicity increasers , Example on the inlet side or air filter side true the dividers eliminate air tumbling at the back of the slide , yes smoothing air flow and directing it under the slide BUT! without a venturei divider on the oposite side of the slide air expands to the full size of the venturi thus decreasing velosity . The dividers keep air speed up all the way through . Therefore its like opening four smaller carbs in series making linear power . It allows running bigger carbs with out the down fall of the slow air speed BLAH! If some one hasnt tried one they have no idea how well it works , I have many customers who would gladly tell you haw pleasred the are with what it does . It has actually been proven to perform better than a exaust power valve . If anyone want to talk to some of my customers give me a call and I will hook you up to talk with them. Many say its the best money they have spent on thier bike . 702-858-9711
Rich
I am not following that explanation. The air passes under the slide and the dividers smooth out flow which creates a higher gas velocity and stronger signal. I get that bit. But what's this about at the motor side? It doesn't much matter when the dividers stop but when they do, the airflow will still be more or less as turbulent as if they were not there at all. Surely?
Except at WOT of course, but at small to mid sized throttle openings, if the passage open up abruptly at the slide or at the manifold, the flow will be just as turbulent won't it? Or is the theory that flow at the discharge point ( just after the slide) needs to be laminar to also be laminar through the venturi under the slide?
I could see an argument that flow just after the slide has to be laminar, but I'm not sure if fluid dynamics works that way. In fact using flow restrictors like the AMA used to mandate actually improved flow through the carb body.
Are you saying that the coefficient of discharge improves with dividers with a proportionate increase in airflow before the nozzle (slide)?
Or is the theory that the reversion waves are trapped and are less disruptive to incoming flow? Logically that might work if they are on the motor side of the venturi..
Whats not to follow? Smaller area means higher velocity. When the dividers are full length of carb and get as close to the reeds or intake port all the more effective . It works . How about a tri power 427 corvette with 3 two barrel carbs of 350cfm each that open progressivly totaling 1050 cfm that works well butif you throw on a 1050cfm dominator carb it wont handle it with out falling on its face , BLAH! because the big venturies have low velocity. You would have to creep up on throttle opening as engine speed was able to move enough air to accept the available air . The point is to have atmospheric pressure fill the cylinder or crankcase as soon as possible while keeping the air moving . Fine line .Again the carbs WORK EXTREMELY well. I hears today from anothee vintage race customer witha 1974 yz 250 who love it , no light switch off on but linear and controlable power.
actually the 6 packs were about fuel distribution in the manifold before manifold technology improved.
However, using another automotive comparison, this always reminded me of the old offenhauser '360' manifolds with the split runners to keep the velocity up. :twocents: but, its hard to have laminar flow with a slide halfway between the blades. but yes, it will improve the signal at low velocity to get it to build better so you don't stall out at the wider throttle openings. what is the surface area in the bellmouth of the front of the blade, persay on a 34mm carb?
the other thing i find interesting is the use of a power jet with the dividers. with the flow directed by the blades straight across, will it go lean w/out the signal going as strong across the lower part of the venturi, and therefore being made up by the power jet(s)? which, is fne, but, just curious as to what the theory here is.
because, with what the smart carb is driving at is the 'directed' flow at the bottom of the bellmouth by their claims and pressurised fuel bowl helping with the atomization by speeding up the fuel out of the jet tube at higher belmouth pressures.
When I instal a intela jet system with dividers the discharge nozzle is below the 3/4 divider and actually contributes to the needle adjustment which is really cool not just wot. And wrong on your tri power theory . I guess you wont really believe it works without trying . We could go on and on , if you dont believe you can ask many of my customers ,
The idea of wing type pieces in carbs has been around for at least 50 years. The fact that the very clever people at Mikuni or keihin, or even Yamaha or any other manufacturer dont use them, and the the commercially available versions have retarded names like scary fast leads me to believe the same as them that it is a gimmick with no real benefit. Long story short, id it worked everybody would have it.
The idea of small carbs for small throttle openings is a well tried idea and is applied in two barrel carbs and of course all those Hondas with oval or figure 8 shaped bores so that at small openings, it's like having a small carb but with an oval carb you get the equivalent of a larger round carb at WOT. We used them extensively on Honda race bikes to get better part throttle response than with an equivalent WOT Mikuni.
You still have not explained why the airflow after the dividers doesn't create the same problem as they are supposed to avoid, but I'd like to see the results on a dyno or other objective data as to how they are better and under what operating conditions.
But to your point, at any particular throttle opening, the area through the venturi under the slide is the same with or without dividers isn't it?
Is it just better tracking between different circuits or actually making more power at some throttle openings?
Quote from: rodneya on July 31, 2020, 11:46:15 PM
Long story short, id it worked everybody would have it.
Wouldn't that be true of any mod...........I guess we all must be wasting our money.
This thread is like an oil thread. Many people are going to have a preference and it's mostly confirmation bias. Nobody is presenting any data, it's all just anecdotes. The truth is, for the majority of people, just getting whatever carb you have to work reasonably right will mean you are doing great. There are plenty of piss poor carb setups out there.
Does the TE SmartCarb make it easier? Well, nobody here knows because not a single one of us owns one.
Quote from: sav0r on August 01, 2020, 12:51:20 AM
This thread is like an oil thread. Many people are going to have a preference and it's mostly confirmation bias. Nobody is presenting any data, it's all just anecdotes. The truth is, for the majority of people, just getting whatever carb you have to work reasonably right will mean you are doing great. There are plenty of piss poor carb setups out there.
Does the TE SmartCarb make it easier? Well, nobody here knows because not a single one of us owns one.
👍🏻
direct port injection proves my point with the tri power theory.. or ls motors would have had 8 throttle bodies, not 1. I mean, sorry going to have to disagree there 100%. also why the 440 and 340 Six pack cars didnt in reality make the power the 4bbl cars did. but the manifold tech at the time got much better . inline 6s were the same way.. look at the hyperpack slant6 for an improved intake vs multiple carbs on a traditional log intake. . but 6pack carb setuos are damn sexy to look at. :cheerleader:
regardless, theres many ways to achieve the same goal. that's the takeaway from all this. I think the big q is, how much better is, if at all, the smart carb vs a well tuned flatslide? and is it worth the much higher price point, or is it just the bling factor, which does have some merit. :twocents:
You dont have to believe it works . But as I said I have MANY customers who love them and I offer names and numbers of them If you want to grill them . Just cuz the manufactures dont have it dont mean that it dont work . So what is the after market all about ? I guess since port work on a factory machine must be ultimate also , and pipes , if the after market pipes worked then the factories would have them . This is ridiclous. I guess Smoky Unik and Bill Jenkins , Vic Edelbrock just had marketing scams .
Numbers speak volumes in debates like this. For the average rider like myself, what's the point? I'd be happy to be able to hop on a bike and just ride. But that's what the cruiser is for. The RD is a simple yet highly debated machine on power output, carb setups, etc etc.
What earns the coveted cash in my pocket is what allows me to ride with less tweaking.
i believe they work, i actually know a few people who have had it done and speak highly about the mod, for sure.
Fuel systems are like donuts. there's many flavors. Use what suits your needs. :patriot:
Dyno numbers would be a lot more valuable than phone numbers.
... and I've had RB's divider plates in my TDR carbs for over ten years now. Really couldn't tell you if they work or not as I did a lot of mods all at once.
The look cool tho :metal:
RB dividers are not bad but he didnt take it far enough to achieve the linear power application. Like a power now drop in does some good but not alot it does nothing to keep velocity up past the slide .
Just for S's and G's I emailed them asking about 28mm carbs for the RD. They said,
"We are just now receiving our new revision 28mm SC2s. They can be outfitted with an oil injection pipe. Please let me know if I can answer any additional questions."
Just get off the wallet and be a Guinea pig. I bet it works well, but that pricetag is crazy.
wonder what the up-charge would be for the fitting? :busey: that answer tells me, they are waiting for enough orders to get a (minimum) run made. would guarantee they dont have any on the shelf, and bet its a 3-4 week lead min, they will tell you its due to demand (guarantee its not). ask em.
They posted about 28mm bodies on July 1st, so they're already in process I'd say.
(https://uploads.tapatalk-cdn.com/20200807/7c2a6112e41173fd0b9a8d8e209e4523.jpg)
advertising & promotion :whistle:
Are intake spigots OD pretty universal or would you have to have them machined?
Check out the discussion over on the RZ500 site; actual testing about to happen!
https://www.rzrd500.com/phpBB3/viewtopic.php?f=1&t=16810 (https://www.rzrd500.com/phpBB3/viewtopic.php?f=1&t=16810)
good. looking forward to it.
:clap: