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Kyledvor61

What carb is this?

22 posts in this topic

This carb was on my yz426 when I bought it. Need jets and dont know what to buy for. I dont see any sort of part number or markings on it anywhere besides the big KEIHIN on the side. I used a caliper and bore indicators and got about 39.5mm. This is a different carb from the 39 fcr that was on my yfz. Whatever it is its pretty trick looking. says "flat cr" on the top. I'm new to the 426, but not the 450.

DSC03776.jpg

DSC03775.jpg

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Whats that knob on the bottom left in the last picture?

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That's a Keihin flat slide seen on some Honda 's the knob is the idle RPM adjustment

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I would remove your jet and take it with you to a Honda shop Honda's have used Keihin carbs forever

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not 100% but that looks just like the carb my 99 yz400f had on it factory.

no hot start, it was on a nipple on the intake manifold. Not sure when they put the hot start on the carb on the 426, but I think the early ones may have been the same as the 400. If so the early fcr jets are different than like your 450 would be.

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Maybe he has a 400?

could be... i only had that carb off about a dozen times :excuseme:

but that sure looks like it....

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I was told its a 426, but with a 450 cylinder and 450 head. Im so damn confused right now since I measured the stroke and it came out same as the 450. its a hot rods crank

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That's a Keihin FCR, as opposed to the newer FCR-MX used on the 426-450. It should have stamped ID marks on it near the float bowl joint on one side which will; tell you the model it was originally on.

As far as Honda jets fitting this, you might want to be careful of that, as the first CRF's used the FCR-MX, not this carb. I believe the pilot and certain other jets are of a different series. FCR's were used on some two-strokes, but the needle jets are different.

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dont think its a honda branded FCR. it appears from the pics to have the removable intake bell. i think the hondas were cast into the carb body.

either way, looks most like a yz400f carb. the 426 and later ones did have the hot start built in. you can also tell the generation from the accel pump. the early non MX carbs had all the linkages and were external. the FCRMX has the pump mechanism built in to the carb body.

these do have some different jets as opposed to the newer FCRMX (pilot jet's different for sure). take the jets out, and go to the local MX shop. they will carry jets to fit it. or, just get a JD Jetting kit for the 400/426. then youll be covered however it needs. although most JD kits i think say to leave the pilot stock.

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I could tell from the stamped ID numbers that I mentioned if you post them.

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The carb is from a 1998 YZ400.

Hey if I gave u the number on my carb u could tell me what it's from I have a yz426 2001 thanks. Having trouble finding a gasket for the center of the carb I have Cuz mine splits in 2 in the center and the diagram at malcoms doesn't show the carb splits in to thanks again

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Hey if I gave u the number on my carb u could tell me what it's from I have a yz426 2001 thanks. Having trouble finding a gasket for the center of the carb I have Cuz mine splits in 2 in the center and the diagram at malcoms doesn't show the carb splits in to thanks again

 

Contact JD Jetting or Sudco.

Finding the body seal is sometimes not possible depending on the model.

You are not supposd to split the body.

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Noooooo that's horrible I wish I would have known I wasn't supposed to seperate the body I need that gasket and like 4 tiny little o rings that go in the center. The oem carb is $1800 on chapperalle.com lol. Oh I hope I didn't f up Cuz I went to malcom smith's and they wore useless if it doesn't show on there pc. But thanks I'll check out the places you gave me. I'll also post the numbers stamped on my carb

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