YZ426 with a YZF450 Carb

I now done with the Carb swap.

Yes the (Quad carb off a 2005 YZF450) works on my 2000 YZ426.

Pro's it much cheeper than using a carb off a YZ450F I found there about half the price on Flee Bay easy to find at less cash out of pocket it now untill others figure this out.

Con's you have to drill tap threads the carb body where the return Throttle cable go's to make it work You dont have to have a return thottle cable if you dont want one thats up to you.

No mather which way you go with a YZ450F this more plug and play no drilling and tapping threads there already there for the return throttle cable, there should be no jetting changes (Drit Bike), YZF450 (Quad), you need to buy new throttle cables for anyone of these set up to work Like I said you can buy a single type throttle cable and throttle system if you want so you dont have to drill and tap the carb body or just hook 1 of the dual cable ( Pull / Pull cables) system up and tie up the other one you not using out of the way.

I had a bike stick wide open on me when travling at very high rates of speed this with a single throtttle cable system bike it bad news I like the pulll / pull throttle system you can force the carb shut and get the bike slowed down and stopped.

Oh ya I didn't crash the bike that was stuck Wide open I just reached down and shut the gas to off hung on until it ran out of gas (Dont panic slow is fast think thing about what you need to do next).

I swapped the Main and Pilot jets from the Stock 426 carb to the 450 carb put the Needle on the YZF450 carb to the 2nd slot.

I used my hot start lever frrom my 426 carb BUT I had to buy a Hot start cable off a 2005 YZF 450 for things to work and had to trim the cable tube comming out of the carb so every things works it is put on the bike and keep on trimming the tube utill you are sure the hot start plunger bottoms out when the lever on the bars is released ask me how I found this out.

If you dont get the Hot start to work right the bike will run but it will not rev out it be running lean.

I had to trim intake boot rubber on the OD from the carb to the motor the Hose clamp is clocked you have to shave off the indexing rubber tab so you can rotate clocking of the clamp upside down so you can get to the clamp screw and if you try to keep the clamp right side up the screw will hit the carb.

The Idle adjustment is where the TPS is comming out of the carb it Nice easy to get at.

As for the TPS there is 2 plugs comming out of it 1st is for the TPS the other for the adj the idle speed you dont need this one tape up the end and tie up to the frame of the bike.

Good luck not hard to do just take you'r time it cost you much less going this route than the carb off a YZ450F.

Edited by marv02

Oh ya make sure if you buy a used carb do you self a big favor tear it all the way apart look at everything very good clean it out real good before put on the bike.

Just because the picture you might see on Fee Bay the carb is drity on the outside it just the outside nothing a good cleaning and a wire brush and some scothbrite can make look new again.

Try to make sure if you do buy a use carb try to find picture of the inside just to see if clean and not full of crud.

I would not buy I much rather have a clean inside of the carb than a pretty outside.

Most of the time it full of crud inside the carb is junk chance you getting like new again is a bad gamble you should not take.

The outside of the carb no big deal.

A lot of the times when some one parts out a bike it been sitting outside for a while so the outside of the carb will look like it water stained just grimy and dirty most likey if they are parting it out they didn care about the bike.

Edited by marv02

I seen YZ450F carb $180.00 on up.

YZF450 picked the one I have for $60.00.

If the carburetor comes off of an '03 or later YZ450F motorcycle (not a YFZ450 quad), there is no drilling involved; it's a straight up bolt-on to a 426. You will need the complete carb and throttle cables, along with the hot start assembly and some sort of lever to operate it with. The stock 426 throttle tube works with the 450 cables. The bike will start and run better than it ever has with stock 450 jetting in most cases. Anyone buying a newer carb on the used parts market should try to get as much of the listed stuff with it as possible so as to make things simple and cheap.

It took me about month and a half to complete his project.


I was not in no big hurry to get it done.


It been about 105 to 115 Degrees outside during this time so for me it was to hot to ride the bike anyways It still hot outside here in in the high 90"s so I still not riding the bike LOL.


All weather bike fair weather rider this comes with age LOL I am 50 years old.


Like I said it's not hard at all converting the YZF450 carb to work just take you'r time I can be done in a day if you wanted to just get all your parts in a row before hand.


One of the reasons It done now my wife asking me when will I put the bike back together so I did so I dont hear it from her anymore LOL.

Edited by marv02


All weather bike fair weather rider this comes with age LOL I am 50 years old.

You have a long way to go yet. :p

My point is that since they cost about the same most of the time, you can avoid all of the conversion work and headaches by buying a YZ450 carb in the first place instead of a quad or WR carb.

It didn't cost anything to do the mod just a couple hours I already had all the tools.

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