Well, it seems I can't make it so.
To get to 570 you have to start with a 530. I can make my 450 a 530 by switching to a 530 crank.
I found one used and in good shape. Saved me a ton ifi got it.
Buuuut, the make the beast with two backsing kit from KTM is obsolete and it seems there isn't one existing on the planet. So I had to bail on the crank.
Plan B: Thumper Racing.
I talked to them for a bit today. They didn't recommend the 570 but instead the 520.
570 uses the long stroke setup, slower to rev but good torque.
The 520 users the shorter stroke 450 crank and rod with a bigger piston. They resleeve the cylinder, bore it, nikasil it and hone. Works with stock 450 carb-cdi-cam.
Seems the 570 kit from KTM uses a husaberg 570 rod (and presumably the piston too) a cam from a 500exc and s CDI with a less aggressive timing curve and 500rpm lower limit.
Their recommendation is the 520 kit, swap to the 500 cam, bore the 39mm carb to 41mm with their special accelerator pump mod to split the stream and more finely atomize the fuel.
He said 60hp, rabid throttle response and fast revs should be easy.
$1290 for the whole shooting match.
make the beast with two backs it. I'm doing it.