05 WR450 carb in 99 WR400?

Will an 05 450 carb work in a 99 400? I think they're all Keihin 39mm.

Well, not much interest on this but for what it's worth, I stuck the 05 WR450 carb in the 99 WR400. Needed swap the pilot jet but it seems to be running right. Going to roost it soon.

Well, not much interest on this but for what it's worth, I stuck the 05 WR450 carb in the 99 WR400. Needed swap the pilot jet but it seems to be running right. Going to roost it soon.

Got any more feedback on this? I have a 98 WR400 and am thinking of doing somehting similar... was the pilot jet compatible between the 400 and the 400 or did you have to buy a new one, if so, what size?

It should, try it and see! make sure to plug the old "Octopus" vacuum port. you may also need the hot start cable and lever system.

the newer FCR carbs are allegedly better than earlier models in regards to longevity and low end performance have been suggested to me for my 426

something about a seal somewhere that gets gunked and also the wear plates. IDK though, this is what I've been told.

I see no reason why it would not work other than having to rejet and figuring the hot start bit.

get one of those fancy auto decomp exhaust cams and you'll have some room where the lever is now to put it???

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