I am thinking in buying a mito 125, 7 speed from 2002, it has 8.000 kmts. , and want to know what are the most frecuently thinks that can broke or go wrong, whith this bike, and what are the service i had to do , because the owner of this bike has no book of service. How many kmts. do whith 1 lt. of gasoline, going slow,(120 km/h) and going faster 160 or 180 km/h in route.