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Just looking to see what carb you guys are using.

On my '90 I had the stock carb and then switched to an RB modified carb.

RB carb on my 03' 220.

RB carb here. Love it.

I bought a new 35 PWK with the JD jetting needles and love it.

The original PWK35 with Fredette’s 1173 needle and jets, #7 slide from Sudco.

RB carb for me.

Sounds like the RB carb is the majority. So why the RB over the stock or the lectron

Fauss1 wrote: ↑10:12 pm Jan 26 2022 Sounds like the RB carb is the majority. So why the RB over the stock or the lectron

Because it does all the lectern does with more crispness for 1/3 the price?

One question… the Lectron self-adjusts for altitude/temperature changes. How does the RB do this?

If it doesn’t, that’s the only difference I’m aware of. However, it appears the Dial-A-Jet kit for about a $100 (with the required snorkel kit) would do this. Has anyone tried one?

https://www.rockymountainatvmc.com/part ... al-a-jet-p

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RB modifies the entire pilot circuit internally, which brings the air screw into play about tenfold what it was stock. Tiny (and I mean TINY!) adjustments to the provided thumb screw as you change altitude keep the carb perfectly dialed in. If I’m going really, really high, I’ll basically give it a 16th of a turn or so every time we stop to take a water break.

That being said, however, I’ve also done some rides where I’ve just left it alone and it’s still awesome.

I love the RB carb because it gives you a crisp clean low end with lots of torque due to his pilot circuit mods and perfectly machined divider which increases air speed through the throat. Now, on top of that, he bores the carb out from a 35 to a 36mm throat which helps you get more top end power. Combine the three mods and it give you a carb with great power and throttle response throughout the entire rpm range. The carb seems way less finicky to jet than any standard PWK carb I've messed with. My bike will still run decent even when going from 2000ft to over 6500ft of elevation but you can tell it gets pretty rich.

I do own a Lectron, though. It was installed on my '11 GasGas EC250R when I bought it. Even after really dialing it in my KDX220 with RB carb has more low end and way better throttle response than my GG 250 with a Lectron! The automatically adjusting for altitude is the only thing a Lectron has over an RB carb. Everywhere else the RB carbs flat out kills it.

Anyone out there who has an extra stock carb they'd like to sell? Shoot me a message. I am bringing back to life a mistreated 94 KDX 200.
I don't know what kind of hurt the prior owners put onto this bike, but tears of mixed gas continue to leak profusely from the current carb. No matter what tricks and rebuilds I perform the pre-mix just won't stop seeping out. Cheers ya'll.

Bhutch1987 wrote: ↑02:55 pm Apr 14 2022 Anyone out there who has an extra stock carb they'd like to sell? Shoot me a message. I am bringing back to life a mistreated 94 KDX 200.
I don't know what kind of hurt the prior owners put onto this bike, but tears of mixed gas continue to leak profusely from the current carb. No matter what tricks and rebuilds I perform the pre-mix just won't stop seeping out. Cheers ya'll.Brap Horse.jpg

Seeping out from where?

The Gas comes out from the drain tube at the bottom of the carb. Doesn't that mean there is an issue with the Needle Valve seat?
The bike starts well but I have to be very very diligent about immediately shutting off the fuel anytime I stop.

Bhutch1987 wrote: ↑01:04 pm Apr 15 2022 The Gas comes out from the drain tube at the bottom of the carb. Doesn't that mean there is an issue with the Needle Valve seat?
The bike starts well but I have to be very very diligent about immediately shutting off the fuel anytime I stop.

Yes, that's a needle/seat/float issue. Make sure your carb is mounted straight, float is set to 18mm, that the needle valave is good, and you might need to polish the needle seat as it might have corrosion/varnish on it from sitting so long. Personally, I would just replace the needle valve with a genuine Keihin one from Jets-R-Us (don't use cheap no name parts in your carb!) along with doing the other two. Also, make sure the float moves freely without any resistance. If it does, polish the float pin/replace with new and where it rides in the float/replace the float.

Here's how to polish the needle seat...