Stock XL175 fitted w/ 520 sprockets which can't find via
http://www.jtsprockets.com/ 
For most vertical Chonda
http://www.chinariders.net/showpost....59&postcount=8. 13T (520) almost the limit for such tight space...
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6v or 12V is a straight forward job... If upgrade to 12v, LED maybe a good choice [Stock stator is quite waek ~100W only... There's more room for E-gadgets/ grip heater...]