Replacement Carb?

[MXonaKawi]

Here's a link for race gas at the pump:

http://www.davebarton.com/Unleaded_Racing_Fuel_in_SoCal

I have bought race gas from Arroyo Parkway Union 76 in Pasadena and at Mark's Union 76 in Fullerton. Both of those stations are listed on Dave Barton's site. I'm not sure about the others listed.

Yes, definitely mix at 32:1. If you choose a different mixing ratio none of the listed jetting specs will apply.

I'll get that photo for you later on tonight.

More great info. Thanks again. Looking forward to that pic!

[KevinTwoStk]

These three photos show the wiring for the fuel cut solenoid. There's a tab on the frame to hold the connector, and you'll find a receiver for this tab molded into the connector housing.

It might look like this wiring goes to the throttle sensor (which you can see in the first photo) but it does not. Instead, it wraps around the carburetor body to the opposite/right side where the fuel cut solenoid is located.

[KevinTwoStk]

Here's the connector for the throttle sensor. It's found just ahead of the airbox pass-through grommet. There's no frame tab for this one, as the connector just kind of floats above the airboot.

In general, the wiring is such that you can't connect it the wrong way once it's laid out on the frame. Incorrect connections either have differently-shaped connectors or they simply won't reach.

[MXonaKawi]

Great photos! That looks completely different than my setup to my eyes. Might just be my naiveity though.

Here are my photos. The first one shows where the throttle tube connects to the carburetor.

The second one shows that grey connector that comes out of the clutch cover.

The third one shows that black electronic box (what is it called? generator?) and it's connection to the other end of the grey connector that clipts onto the frame tab.

[KevinTwoStk]

There's a frame-mounted tab for the stator-to-ignition module connector. That one is further up the frame rail toward the steering head. The connector has four wires.

I took this photo during my teardown, and it shows the connector in question.

The Keihin PWK Power Jet carb uses a second frame-mounted connector for the throttle position sensor, as you saw in my photos. This connector has two wires.

You might have an easier time determining what you've got by setting the engine into the frame and seeing how well the wiring reaches.

[KevinTwoStk]

Can you snap a pic of the complete wiring harness (the section with the black box) laid out on the floor? That way we'll be able to see the whole harness.

[MXonaKawi]

Can you snap a pic of the complete wiring harness (the section with the black box) laid out on the floor? That way we'll be able to see the whole harness.

Here it is!

[KevinTwoStk]

Comparing that to the diagrams of the '99-'00 harness (Keihin PWK Power Jet) and the '01-'02 (Mikuni TMX) I'm positive you've got an '01-'02 harness.

I think your best bet is to run it as-is with the Mikuni. JD Jetting offers a jetting kit for the '01-'02 Mikuni-equipped KX 125's. I'd get one of those to eliminate a lot of guesswork and frustration. The factory service manual specifies a 32:1 mixing ratio for the '99-'02 model years that are covered in the manual.

Unsolicited spark plug info:

The NGK BR9EIX is specified, but you can also run the NGK BR9ES which is about a third of the price. I've swapped between the expensive BR9EIX and the economical BR9ES and I can't tell the difference.

[KevinTwoStk]

On our engines, the case reed configuration puts the bottom of the carb very close to the cases. My bike came with a small rubber pad that fits between the carb's float bowl plug and the case. From the photos, I couldn't tell if your engine cases have it or not. If not, I would get one from your local Kawi dealer.

It also looks like you could use a new throttle cable. Make sure the rubber boot gets pushed all the way to the top of the carb so it seals the throttle cable housing and the top of the carb. Left without the boot, it's a perfect place for dirt to get in.

That's just going off of the photos. If the cable looks good up close (along with the condition of the boot) then you can definitely run it.

[MXonaKawi]

Thanks man. Ok I'm going to stick with the Mikuni then. If I buy a brand new Mikuni TMX35 off ebay will I still need a jetting kit? If so, then I will grab one of them as well.

-I am definitely going to get a new throttle tube, and cable.

-I'll look into that rubber pad as well.

-Can you explain which part is the 'harness'?

[KevinTwoStk]

The main wiring harness is everything immediately connected to that rectangular black ignition control box.

I have a longer answer concerning your carburetor but will have to post it later when I have more time.

[MXonaKawi]

The main wiring harness is everything immediately connected to that rectangular black ignition control box.

I have a longer answer concerning your carburetor but will have to post it later when I have more time.

Sounds good bro! Thanks looking forward to more insight!

[KevinTwoStk]

My question is: what's wrong with your current carburetor?

If it's in bad shape, I can see needing a new one. Of course, it's your bike and your call.

The '01 KX 125 used a Mikuni TMX36, while the '02 went with a Mikuni TMX38. Most 125's use a 36mm carb. Theoretically, a 38mm will provide better top end power but at the expense of low- and mid-range power. So I'd go with a 36 for better all-around performance.

'01 carb specs per the Kawasaki service manual (Kawasaki p/n 99924-1244-04)

Mikuni TMX36
Main jet: #360
Throttle valve cutaway: #5.5
Jet needle: 6BEF16-69
Jet needle clip position: 4th groove from the top
Slow jet/pilot jet: #50
Air screw (turns out): 2.0
Service fuel level (above the bottom edge of the carb body): 3mm plus or minus 1mm
Float height: 15mm plus or minus 1mm

The stock specs are a starting point. Odds are that you'll have to do some further tuning, which brings us to the JD Jetting kit.

The value of the JD Jetting kit (which I still think is a good idea) is the research and development that went into it. JD's R&D can save a lot of guesswork and frustration.

If you keep your existing carburetor I would also purchase new gaskets for the top of the carb and for the float bowl. If the carb top gasket leaks you'll be leaking extra air into the engine which will make it run lean and in turn risk a seizure. If the float bowl gasket leaks you'll be dribbling fuel all over the cases: flammable and messy!

[KevinTwoStk]

Final thought for now:

Since you're planning to replace your throttle, I'll throw my two cents in:

I replaced my stock throttle assembly with a quick-turn throttle from G2 Ergonomics. The machined aluminum throttle tube is nice, but the bigger benefit is that you won't have to twist your wrist as far to get the throttle wide open. You won't have to "re-grip" the throttle as you go from low to mid to WFO.

The quality is impeccable and the staff is pleasant to deal with.

www.g2ergo.com

[MXonaKawi]

As far as I know...nothing is wrong with my current carb. It's a little scraped up which honestly bothers me a bit but not enough to replace it. However, that is not my main reason for wanting to swap it out. My main reason is that I want this bike to be as "brand new" as possible for a 13 year old bike. So, if I can get an important part like that brand new for $150 bucks...it seems to me like a small price to pay for peace of mind as far as my carb goes. The more brand new parts I put on this bike, theoretically, the less parts I will have to comb through if there are any issues when the build is done.

i.e. If the bike doesn't run or start once it's all back together, I'll know it's not the carb (theoretically). Either that or I don't know wtf I'm doing as far as jetting. But you know what I mean.

I want this bike to run as if it were 2000 and I just bought it brand new. And I want it to last for a good 6 or 7 years.

Also, to me, there is something exciting about starting from a clean slate. When I got the bike it looked like someone mistreated it for a long time and I personally have a thing for new, shiny, mint condition things haha (I'm kind of anal retentive)

Starting with a brand new carb out of the box, ordering the jetting kit, jetting it to whatever specs we find suitable, and then putting it on the bike just makes it more gratifying when I stand back and stare at my finished product for 2139808124 hours. haha