YZ450 motor in 01' 426 frame

[dbleon]

I was just wondering for the sake of wondering if the 450 motor would bolt up in the 426 frame??? Any ideas???

[grayracer513]

It will probably not bolt up, but it shouldn't be especially difficult to do. The two most difficult points would be in adapting the rear hard point on the engine to the '01 swing arm and the lower mount bolt. The steel sleeves at the rear of the crankcase can be removed and modified. The lower bolt passes straight through the frame, so it can be quite a problem if it doesn't line up.

There is, however, no conceivable advantage to doing this, since the 426 frame alone is 6+ pounds heavier than that of the 450, and a complete early 450 is just not that expensive anymore. It's a lot of work for not much gain.

[yz454]

It will bolt up ,the bottom motor mount is 10 mm off.

[grayracer513]

the bottom motor mount is 10 mm off.

Then how does that "bolt up"?