ATV (All Terrain Vechile) is a natural exploratory vehicle that is a blend of 2-wheeled vehicles and 4-wheel vehicles. At first ATV is used in plantations, but along with the development of ATV time is used as a natural explorer vehicle. ATV uses a 2-wheeled vehicle engine but has a reverse speed. This study was conducted to determine the transmission system on ATV Toyoco G16ADP 160cc. The disassembly of the transmission system is carried out to determine the type of transmission used, perform the transmission measurements, compute the gear ratio, calculate the output of rpm output, and calculate the torque, know the type of gear used and lubrication system. The data obtained from dismantling is the transmission of Toyoco G16ADP using the type of transmission constantmesh and sledingmesh, in the measurement of all components are still in good condition without wear and tear, the lubrication system is very simple with the use of gear rotation to lubricate, the calculation of transmission ratio shows in the transmission back to get value The largest torque, and on the transmission speed 3 results of the largest rpm output.