No elevation change factor
Pro Circuit Platinum Pipe / silencer
Stock motor
I have an RB carb on my 200, and its great. As we know they are unavailable. Thx for the replies!!





As of my last email from Ron in mid August, he didn't have any carbs and didn't know when he would have them, if at all.doakley wrote: 12:25 pm Nov 18 2021 I thought Ron Black was still selling new, modified carbs but would no longer modify an old carb. Of course I've been out of the loop on that for almost a year. If I couldn't get a new carb from Ron, I'd go with Lectron.

I am not crazy about the price of the Lectron and the issues with the install. Although I know many guys have made it fit, I want a bolt on carb with zero headaches esp after seeing the price!!!SS109 wrote: 04:34 pm Nov 18 2021 RB carb all the way, hands down! If he isn't doing new carbs still then the PWK 35 AS. I have a Lectron on another bike and I'm not sold on it. Maybe if you like a more mellow feeling bike, and no real tuning after you get it set up, then the Lectron might be for you. Just know they fit like crap on a KDX. Of course, I only change needle clip position on my RB carb from winter to summer and the main only if I ride above 5000" by one size. Super easy carb to tune IMO/IME.




Greenblood, what performance differences with the slightly larger carb are you experiencing?@greenblood67 wrote: 06:07 am Apr 07 2026 I upgraded to a 35mm carb from stock 33. Bought on ebay. No need to mess with jets, runs just fine as is.



billie_morini wrote: 11:30 am Apr 07 2026Greenblood, what performance differences with the slightly larger carb are you experiencing?@greenblood67 wrote: 06:07 am Apr 07 2026 I upgraded to a 35mm carb from stock 33. Bought on ebay. No need to mess with jets, runs just fine as is.
I assume this was directed at me, ref: our conversation in the Smart Carb thread.Chuck78 wrote: 11:53 am Apr 07 2026 Those two carburetors are undeniably the best for those who understand them and give them a chance, as opposed to old timers who swear them off without actually knowing how they work or even giving them a chance.

Nick, I actually was not in any way directing my comments which you'd quoted at you whatsoever, but I did have another KDX owner in mind who fits the description far more appropriately than you do... he's not a member here. As well as a lot of cranky old 60+ year old guys who still think that Nikasil plating is a scam, and that all cylinders should be sleeved... A lot of people, particularly people in that age range and up, base their opinions on Lectron technology from the 1980's & 1990's. Things have changed significantly in the past several years with metering rod carb technology.Slick_Nick wrote: 09:37 am Apr 09 2026I assume this was directed at me, ref: our conversation in the Smart Carb thread.Chuck78 wrote: 11:53 am Apr 07 2026 Those two carburetors are undeniably the best for those who understand them and give them a chance, as opposed to old timers who swear them off without actually knowing how they work or even giving them a chance.
I don't like meter rod style carbs.
They are not as crisp as a properly jetted "traditional style" carb. They can't be by their very design. The metering rod smooths out power delivery. I do not like that. It makes the bike feel lazy and mushy. I like sharp, quick response for the riding that I do. If you like the softer power delivery for the riding that you do, it might be a better choice, but don't try to make the Smart Carb out to be something that it isn't. Some riders liked the mushy feeling of the old CV style carbs too, and that's fine if that's what suits the riding that you do.
I understand the Smart Carb, how it works, how to tune them, and I am very familiar with the Keihin PWK family, having tuned it extensively over the years. The PWK has always given me the best results throughout the elevation range that I ride (4000'-9000') The issue I've seen is that people go from a tired, old, improperly jetted PWK to a smart carb, and notice the improvement it gave, so they stop there. Me, I like to squeeze every ounce of performance AND rideability out of my machines, fine tuning is in my blood. I've never been able to do that with the meter rod carbs vs the "traditional style." There just isn't as much adjustability there.


Keep in mind with some users never being able to get the metering rod carbs dialed in right, there are also a countless amount of people who are never able to get jetted Keihin and Mikuni carbs dialed in right.... And also an equal number of people who think they have their carbs dialed in perfectly, yet on many others standards, they are far from perfect, but ignorance is bliss in those cases... until they experience otherwise! I have blown a few minds by swapping needles and jets and even just dialing the air screw in as to how much more performance was left on the table prior.SS109 wrote: 08:23 pm Apr 09 2026 I've used both, PWK and Lectron.
I love my RB modded PWK on my KDX plus it fits perfectly.
I've heard good things about the newer Lectrons and SMartcarbs but I've also heard of some never being able to get them dialed in right.

Chuck78 wrote: 10:06 pm Apr 09 2026Keep in mind with some users never being able to get the metering rod carbs dialed in right, there are also a countless amount of people who are never able to get jetted Keihin and Mikuni carbs dialed in right.... And also an equal number of people who think they have their carbs dialed in perfectly, yet on many others standards, they are far from perfect, but ignorance is bliss in those cases... until they experience otherwise! I have blown a few minds by swapping needles and jets and even just dialing the air screw in as to how much more performance was left on the table prior.
I would be willing to try one but not on my dime. I have my RB 36mm bored PWK35 original type carb dialed in darn near perfect so it wouldn't be worth spending the money on one for me. I can't see it giving me enough performance improvement to justify the cost. Maybe if my bike had a worn out carb I would seriously consider one.Chuck78 wrote: 10:06 pm Apr 09 2026I have an RB 36mm bored PWK35 Air Striker Quad Vent with divider plate etc. it's an excellent carburetor, one of the best. But with the fuel efficiency of these latest generations of metering rod carbs, and the incredible throttle response, I very much appreciate their technological advances and performance.