450 motor in 426

Hey i am new to this site. I jst purchased a 2001 yz426f and the engine is toasted in it. I was wondering if a yz450f engine will fit in that bike, and if so are there any major mods i would have to do to make it work. Will the 426 carb work with the 450 engine?

For the price of the motor you could probably get a whole 450????

For the price of the motor you could probably get a whole 450????
There's one on eBay right now for $1900. (or more, I don't know what the bid is on it)

Yes, it should fit, but the hard points MAY have been relocated slightly, so it might not bolt straight up. I doubt it, but I just don't know. The part numbers are different for the engine brackets, so that may be all you need.

It would still be heavier than an original YZ450, too.

This was discussed back when the 450 first came out, and it was decided that it would not work if I remember right. I think the big issue was getting the swingarm pivot to line up right, but I can't remember for sure. It could probably be done, but it would require some cutting/welding on the frame I'm willing to bet.

Cowboy is correct.....it will not fit. You would have to modify the 426 frame and the oil lines would have to be replaced.

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