Has anyone out there converted a BETA 125 to a 200?

I maybe getting an 06 125 for my son and wondered if it would be practical to convert it to a 200 at a later date.

I have been on the BETA website and cannot find any tech details to see if the stroke is the same.

What parts would be required? Any idea of the cost?

Thanks in Advance

From what I under stand all Rev 3 have the same stroke or bottom end, you just need a 200 kit. Cylinder, head and piston kit.

Even the 270/250 can be made into a 200.

I did some looking around about changing a 200 to a 250 ( out of intrest ) and from what i can remember the stroke was not the same ( I was only going on the part numbers of the crank ). The 125 is the same as the 200 so yes you just need a 200cc cylinder kit but the 250 and 270 are a longer stroke than the 125 . If anyone can confirm this I will also be intrested to find out for sure.