http://www.motorstar.com.ph/products/msx200-ii Why not ask details from them?
Nothing stamped on engine? 16*FML
http://www.mychinamoto.com/forums/showthread.php?642 / 19*cc gives some hints
http://item.taobao.com/item.htm?id=568109497158
Anyway most OHC 196 are 63.5*62.2
http://zse.cc/productsdetail.aspx?Pr...=366&CateID=43
ZS CBB200 65.5*59
https://item.taobao.com/item.htm?id=521223054840 Not much info from 'net to mod these balanced 65.5...
Conventional 63.5 is exact Honda copy, so mods from similar bore/stroke Honda should applies on them...