125-200cc Just Bought 2012 WR125

Good choice. We sent the head and carb off our 2011 TM 250SX to Ron and in a word.....AWESOME! Let us know how it works on the WR please.

Just a follow up to this and how I solved my 2012 WR125 dead spot. I ordered the powervalve spring kit from Halls and here is where everything is set at and I'm happy to say it rips and runs like a 125 should. I can say with certainty that the powervalve springs are the key to the equation. You need this kit if you have a WR125!
Running the large yellow and small silver spring form the spring kit
PV arm is set almost to the top
main - 450(stock is 460)
Raised stock needle one slot(one step richer then stock)
pilot - 45(which is stock)
air screw is 1 and half turn out
idle was reset so it will just stay running
Much thanks to Wallybean for putting the time and effort into the powervalve spring kit.

At the very least you should get the richer Suzuki needle. Then you can drop the pilot down to a 25 or 30. It really helps a lot to get more fuel in there. The most bang for the buck is the RB Designs carb mod. Way more bottom and mid range than any other carb mod.

vntgmx,
I actually tried that combo and I had a major dead spot right before the motor jumped on the PV's and was almost to the point of uncontrollable. It was an abrupt change from "not on the pipe" to "on the pipe" I ended up back to the stock and silver and this bike has awesome power of idle and a super smooth transition to WOT and rips it's a@@ off. Do you have the RB mod carb? If not, this must be the difference. I too have the RM needle. After all day messing with some jet and spring changes I changed the main only from my last settings and completely love this bike.
52 rear sprocket
RB carb mods
#5 slide (RB)
460 main (dropped from 470 which made WOT "seem" to drop off early)
rm needle 16-62 middle clip
35 pilot
1 1/2 turns AS
PV arm about 3/4ish to top
stock/silver springs
40:1 standard pump premium gas

No RB carb mod....just running the stock setup with some tweaked jetting as I noted....I just threw where I'm at with PV and jetting so there's a reference point for those who want to try to work with the stock mikuni.....
If I went with the RB carb mod or if and when I put the 144 kit on I would run the stock and silver springs instead of the current combo I'm running so what you're saying being you have the RB carb mods confirms my thoughts on the PV spring combos....
With my current setup it rips smoothly thru the powerband and I finally have rid of the dreaded dead spot....

wow, just read through this whole thread. I bought a brand new ktm200xcw a year ago and used it for a season of fun in the woods riding with friends and had a rekluse in it. that thing was the best 2 smoker i ever had. like a little tractor...I was thinking of getting a 12 wr125/144 this spring as a new woods ride...but not sure now....i currently have a 2010 smr450 and would like to stay in the same fam, but this has me thinking other wise for my dirt toy....granted im not a racer, this is just a woods bike to play with on the weekends for fun....keep us posted on this!

Once the bike is dialed in you wont regret it. Go with the 144 and the only thing you might want is Walts 165 kit. I am used to bigger bikes like 250 2strokes and up. The WR is a major woods weapon and I didnt even ride mine much yet. My bike was used and had the Mikuni on it with the factory 144 kit. It came with a Keihn as well in a box. I swapped them out and noticed a huge difference right away. I also adjusted the power valve and that helped a lot. Follow my posts over the next few weeks if you want. I just installed the WB165 kit and will be doing some testing with a bunch of different parts. I plan to test back to back with my '03 YZ250 that I raced last year.

sweet, thanks for the heads up and i'll be sure to follow along your posts. I emailed rekluse and they said they are still working on a clutch for the WR125/144.