2002 Yz426 carburetor swap?

Hey everyone, I've heard some stories flaoting around the internet about swapping the 426s carburetor to a newer year as well as it being a yz450s. My question is what is the newest/best confirmed fit carburetor for the 2002 YZ426? I heard of a couple people switching to a 2008 YZ450f carburetor.

 

any imput/thoughts on this would be much apprecheated! thanks.

I am about to put an 07 450 carb on my 01 426. The carb is on the bench now. I will be install it this week. Looks like a very straight forward swap if you have the throttle cable and hot start assembly in hand. The old throttle cable will not fit correctly on my 01. I will post my results when it's done.

Any of the YZ450 carbs will fit exactly the same.  All have the cable operated hot start, and all will need their own throttle cables, but apart from that it's a bolt-on operation.  The best carbs are '05 and later, due to their more sophisticated internal plumbing and the inclusion of a leak jet in the pump circuit.

I put an 07 on my 98 yz400f that I got on eBay for $150 and it fit pretty well, it was a little small but the boot can be stretched per Gray's instructions (posted hundreds of times in TT). I'm not sure how much better the bike ran with it over stock as I bought the bike needing a new carb. It does rip tho and I like the hot start on my bars way better. I went to my yamaha dealer and ordered the hot start perch that bolts onto the clutch perch (like $5). That along with my hot cam modernizes a classic. If you do get a newer carb off ebay or somewhere make sure you get the hotstart and throttle cables as well (as per Gray's instructions).

Thank you all for the quick replies! I'm glad to hear it's an easy swap, I just ordered the parts needed for my bottom end rebuild, so this will have to wait a little while but I'll keep my eyes out for a good deal on a carb w/ the hot start assembly.

Couple more quick questions I just thought of, when swapping over to a new year does the jetting need to be changed? Or will the stock jetting for that newer year carb work for my 426? (I've tackled just about every job on this bike accept jetting lol)

And what year did yamaha go to EFI? Wondering if I could go for the last year carbs were put on the 450s ;)

I am about to put an 07 450 carb on my 01 426. The carb is on the bench now. I will be install it this week. Looks like a very straight forward swap if you have the throttle cable and hot start assembly in hand. The old throttle cable will not fit correctly on my 01. I will post my results when it's done.

What timing! Sounds awesome looking forward to hearing what you have to say about the difference in the power delivery/smoothness thanks!

What timing! Sounds awesome looking forward to hearing what you have to say about the difference in the power delivery/smoothness thanks!

The timing is perfect. I have been thinking about doing this for awhile as I have always fought with my carb and jetting in hopes of getting it to run like my 04. I found out yesterday that part of the hot start assembly on the carb I have is damaged so I ordered a replacement piece online. Won't have the carb on for a week or so, but I'll let you know my results when I do.

Good luck

What timing! Sounds awesome looking forward to hearing what you have to say about the difference in the power delivery/smoothness thanks!

The timing is perfect. I have been thinking about doing this for awhile as I have always fought with my carb and jetting in hopes of getting it to run like my 04. I found out yesterday that part of the hot start assembly on the carb I have is damaged so I ordered a replacement piece online. Won't have the carb on for a week or so, but I'll let you know my results when I do.

Good luck

Sorry to hear about the hotstart assembly, keep me post with the results! :)

Curious, will you keep ur stock getting for your bike? Or use the 07 stock jetting? Or just going to jet the bike your self?

I've never been a fan of the stock jetting. It's always too lean for me. The 07 carb came from the previous owner with:

Main 160

Needle 4th clip

Pilot 48

Start jet stock

Leak jet stock

All I am going to change for now is the main jet. I put a 168 in it for my starting point. (I'm riding slightly above sea level)

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