'01 426 easy carb removal

16 replies to this topic
  • ripntear

Posted September 08, 2004 - 07:26 PM


Hey scooter buddies,

I bought an '01 YZ 426F last weekend from a friend. Drove to Dallas and back in 13hrs. Whew....glad that's over!
Anyway, I didn't even start the bike up untill I got home with it. It fired right up but will not stay ideling. Took it up and down the block and it pulls hard and seems to run great for the little time I have spent on it but dies as soon as I let off the gas.
The bike has been sitting for 2 years, with an occasional fireup to keep every thing lubed. I want to pull the carb and clean it up, but man.....how much stuff do you have to disconnect and unscrew to get the thing out? I have the tank off and have looked at every angle trying to determine the quickest way but got tired and thought I would turn to my friends who have been there done that to walk me through the steps. :thumbsup:

Thanks ya'll,


  • Fastest1

Posted September 08, 2004 - 07:53 PM


The easiest way in the long run is to remove the subframe, it will give you plenty of room. Only takes a few minutes. You can take it off without, but room will be tight.

  • yzf_rider400

Posted September 08, 2004 - 08:42 PM


I just had to do my carb on my 400. You can get it out without taking the subframe or airbox off but you'll need to scrunch the airbox lip back and tuck it against the frame. From there though it will be take some finesse to remove the carb.

It can be frustrating, so you might want to save yourself the headache and just take the subframe off.

Oh, and make sure to clean out the accelerator pump. I don't know about the FCR2 carb (I think that's what's on your 426) but on the FCR1 carbs the a.p. gets really dirty.

Also watch out for all the little parts especially the o-ring on the pilot screw, if you decide to remove it. :thumbsup:

  • skthom2320

Posted September 08, 2004 - 09:04 PM


I've had the carb off, needle pulled, clip position changed and the whole thing back on in less than about 15 minutes or so. The hardest part is threading the stupid vent hoses back in.

No need to even take the tank or seat off.

1. remove the dust cover on the right side to gain access to the throttle cables. Sometimes loosening/removing the coil is helpful to gain access.

2. loosen and remove the throttle cables, a long skinny screwdriver helps to get the top cable out

3. loosen the intake book and the airbox boot

4. remove the fuel hose

5. scrunch back the airbox boot and remove it from the intake of the carb

6. pull carb/hoses out

Whatever you do, do NOT take the carb apart, other than the float bowl off or cleaning the accelerator pump. And don't put the slide plate back in upside down - it will fit then make your scoot run like crap.

If you just need to change the needle/clip position, don't remove the throttle cables, just let the carb hang by them.

And lastly, no need to do the BK/GB mod on an '01 unless you just like to tinker. The jetting can be dialed pretty well with clip position and pilot/main jet changes. About the only thing I couldn't get rid of with the stock needle was a little 1/8th throttle sputter (steady throttle) when it was VERY hot and humid (when I lived in Texas).

  • yzf_rider400

Posted September 08, 2004 - 09:59 PM


just had to add that threading the hoses back inbetween the swingarm can be greatly aided by an allen wrench used as a hooking device. Makes it easy to pull the hoses over the metal lip so you can grab 'em and pull them the rest of the way down.

  • sirthumpalot

Posted September 09, 2004 - 04:00 AM


To add to removing/replacing the carb; shoot the inside of the boots with a very slight shot of silicone spray and the carb will slide in/out of the boots 100% easier.

  • Fly-nBri

Posted September 09, 2004 - 10:31 AM


Definately invest in an owners manual. It will save you tons of time and agony. Then when you DO need to take the carb off and clean inside....you'll know exacly what to do. :thumbsup:

  • 4two6stroker

Posted September 09, 2004 - 12:17 PM


I was asked when I bought mine if I wanted the disc mannual. If you have a computer/printer at home this could be ideal. I'm taking mine back appart at this moment too. Mine doesn't fall back to idile like it should. It's most likely dirt but we'll see. It's time to change the hose anyway the ends are dirt stained. I removed the subframe to aid in cleaning the bike completely. I recomened getting the fuel screw you can adjust by hand. I travel ride to alot of elevation change but not enough to move the clip. This helps in fine tunning trail side so you don't have to listen to the pop or backfire. :thumbsup:

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  • ripntear

Posted September 09, 2004 - 06:03 PM


Thanks everyone!

Removing the subframe helped big time. Got the carb off and held it in my hands like a new born. It was like giving birth...I guess. Anyway, I had a completely clogged pilot. Cleaned it out and blue every thing else out. Put everything back together, turned the gas on and guess what.....Fired right up! :thumbsup: It idled fine but once it warmed up good, there was a little hesitation off the bottom. I bet it is the fuel screw. I do plan on buying one with the knob for easy adjustment. Once again, thank each and everyone for your input. You guys are great :devil:


  • Hamish

Posted September 10, 2004 - 02:10 AM


I never remove the subframe. loosen the front clamp, remove the rear clamp, pull the boot back and out she comes :thumbsup: After trying virtually every clip position on the 2 JD needles I got a lot of practice

  • ripntear

Posted September 10, 2004 - 03:22 AM



You say out she comes. Did you disconnect you throttle cables? How hard is the slide to get to change you needle position?


  • skthom2320

Posted September 10, 2004 - 07:41 AM


If you just remove it from the boots and let it hang by the cables, all you have to do is remove the allen bolts on the top of the carb, remove the allen bolt inside the carb, then twist the throttle to pull the slide up and WHAM - there's the needle.

All of that is very easy to do trackside.

BTW - when changing the clip, I always put the needle inside a sandwich baggie so if the clip tries to spring away it has nowhere to go.

Also, pick up a few extra "e" clips from the hardware store. I forget which size they are, but you can match them up.

  • ripntear

Posted September 10, 2004 - 09:31 AM


Which side are you letting the carb hang from? The plug coil is in the way on the right side, and there isn't enough cable slack for it to hang on the left side.


  • skthom2320

Posted September 10, 2004 - 10:06 AM


I have an '01 426 so we are talking about the same bike. It'll hang from the left side - there's not enough room to do anything on the right.

Just turn the bars all the way to the right (I think - maybe left since it's been a while), and pull those cables down! You might want to pull the tank and check your cable routing.

  • ripntear

Posted September 10, 2004 - 10:15 AM


I'll give it a shot. I bought a new ZipTy fuel screw today and will install it tonight.


  • Hamish

Posted September 11, 2004 - 01:46 AM


just what skthom said :devil:
The bag idea for the clip is a good one.

  • ripntear

Posted September 11, 2004 - 08:07 PM


Thanks again guys,

It sure is nice to have all this wisdom at your fingertips. I installed my new ZIP-Ty fuel screw......SWEEEET! I had tinkered with the old screw for what seemed like an hour and never got it dialed in. Put the new one in and within 5 seconds it was purring like a kitten. It is soooo easy! If you do not have one, I highly recommend it.
Thanks again,


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