125-200cc 2012 WR 144 OEM Mikuni vs. Keihin pwk

A high float will also cause poor gas mileage.

Check your float. Mine was off and I dont think the bowl had ever been opened.

I screwed with jetting almost every ride with the mikuni, put on the motosportz PWK and havent touched it in 2 years. That said, I gave my stock mikuni to my buddy on his yz125, and he loves it. Go figure.

Yeah my float level was way off....I don't think it was ever set properly at the dealer. I had to lower it, and now it only drips if I lean it past the stand. Thanks guys.

I have done A LOT of carb testing on my 11 wr300. And I now like the tmxx better than the pwk. If you want more snap from the Mik, take a small grinder or file the the small half hole on the reed side of the slide. I made mine wider, not deeper and it made it very snappy.

Can you post pictures of this? Did this mod help off idle response?

I just picked up my '12 WR 125. The Mikuni will be going to RB for mods before I even fire it up.

Good move Get the works...My 144 rips with it.

Please post some pics if you can, I am interested in possibly doing this.Thanks!

Yep. The RB mods make an amazing difference. Not even the same carb.

^^^ that's the truth

There is always one guy who is different All my Husky be it my 125 or my 165 or my 250 or my 300 run the stock carb
Both the 2006CR 125 and the 2008 CR 165 run the same carb same setting same everything.Runs perfect every where from sea level to 8,000 feet.Watch my last 2 videos and tell me the bike does not sound like it is running great.Then there is my 2006 WR250 also stock carb My 2010 CR 300 which was the motocross action bike
which pro circut but the big motor and keihin in I purchased that bike but now with a stock motor still cr electronics but it had the keihin carb.The bike ran bad even afte I purchased a JD carb kit I still could not get it to run correct.So I took the 2006 carb off the WR 250 installed it on the 300 and it now runs perfect.Then I had Walt find me a old 2006 mikuni which I set up like the now 300 carb and bingo the 250 runs great.As for the keihin I traded it off for another stock carb.
So I am the odd one out my bikes run fine to me with the stock carb.I also run race gas and some where around 35 to 1

I have the stock mikuni tmxx on my '10 wr144 and it runs very well with no bogs or blubbering. I am just fine tuning the jetting now to see if I can make it even better. All it took for me was patience and learning how much each circuit over-laps another,plug readings ,and listening to the bike (it will tell you what it wants if you listen). I got base-line settings from the jetting threads in this forum and adjusted from there.Once I am satisfied that I can't improve the jetting any further, I will post my settings in the jetting thread and hopefully help out others like they helped me. That's what's great about this forum!

I am on the fence abut the PWK it did help my wr 125 down low but missed the revvy feel of Mikuni .
Has anyone got the older TMX to run well on a wr 125 ?? I dont think the same rm needle trick applies . I guess the divider plate is the go .

can someone recommend a good source to buy a brand new Mukini for a wr125? I want to keep the stock one and send another one to RB.

There should be lots of them laying around from riders who switched to Keihin. Have you tried the wanted section here on CH?

I've got a basically new tmxx I'd sell for $100. Includes stock needle, RM needle and whatever jets I've got left over.
The pwk36 is magic on my 125, so the tmxx has been sitting around collecting dust.

mine works really well but has the cr ignition, timing advanced 3 degrees, diy divider plate and slide reshaped and the jettting is 27.5 pilot and 370 main.i will be fitting a bigger main and lowering needle to try and clear up some loading on long slow sections (2 nd gear just off idle).