I was wondering if a fe570 cylinder , crankshaft & rod, piston would work on a Fx450 chassis . The cases, head, throttle body has the same part numbers
As far as I understand, then yes. Cam is different too, and mapping.
(Depending on cost, you may want to check out Thumper Racing's 104mm piston/cylinder and/or +6mm stroker crank - there's also a 102mm piston/cylinder combo out there.)
the head is also a different part number but I am sure 450 head would work fine with 450 cam/570 cylinder/piston but maybe the piston pin is also different diameter and you also need rod....
Yeah, as the 570 is 100mm instead of 390/450 95mm it makes sense the head is different. The question is if that extra 2.5 matters? If yes it can't be hard to change it to fit.
In Sweden some people have converted 450s to 570s.