http://www.cscmotorcycles.com/Articles.asp?ID=304 answered ur Q's
Needs these TT250 parts: stator + rotor + reg + CDi
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CG "8" often = 88.6mm that can changed to direct-fit "12"
https://item.taobao.com/item.htm?id=1651715694 ONLY
93mm (needs new flywheel) config had more options...