no a 250r motor will not fit in a 200x frame but it will fit in a 250r frame
The 125 forks should fit the 250 as long as they are both the same frame style and close years.
no.
Yes, but you will need do some fabrication to the frame in order to fit it in correctly.
Size wise, it would fit, however it wont bolt into the frame if that is what you are asking.
Oh, dude, if you're asking if a YZ250 motor will fit in a YZ125 frame, technically, yeah, it could fit if you're cool with some serious modifications. Like, you'll probably need to do some custom fabrication work and maybe sacrifice a few weekends in the garage, but hey, anything is possible if you're willing to put in the effort. Just don't expect it to be a walk in the park, ya know?
no
Yes it should fit the frame not sure if tank will fit as the 91 barrel and head are bigger
Should fit it's the same generation motor.
nope
Not without modifications, no
Yes