YZ450f 2004 motor into 2007 frame.

Hello good people. This is my first post here. I have a completely blown 2007 yz450f the motor is out of my budget to fix. I have found a 2004 motor at the right price and need to know if I will have any dramas fitting it. I had a bad experience with a wr and differences between years and did my dough on it. Just trying to avoid heartache on this project. Can anybody offer any guidance?

Thanks in advance.


The engine was completely redesigned when they went to an aluminum frame. I'm sure with some custom fabing you could make it fit, but if you are looking to just drop it in and bolt it down, it will not be that simple or that cheap.

I cant tell you much about fitment off the top of my head, but I could post pictures of my 05 and 08 in their frames and where they mount. I can imagine the upper engine mounts will be very different.

Well the deal is the rear and bottom mounts line right up. I think if you use the front and top mounts from a alloy 250 every thing will line up close. a big issue is the oiling system the 05 had an external tank ( the frame) the 07 internal. here again digging into the 250 parts bin you can use the oil tank and lines from a alloy 250 ( you might need to add tabs to the frame) or the dubach wetsump kit will work on the 03-05 450's as well. the pipe is an issue the angle of the cylinder is not the same but now that your going to be a fabricator this is workable. In this e-bay age I find it hard to imagine that you cant find the parts to fix your 07 at a fair price considering the 05 motor is worth cash to put towards it?

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