1888a123_Beginner_Dirt_Bike___GICL_Wiki_Dirt_Bike_Parts_List_Function
[Part and Quantity] Engine Block (1) [Part Number] DR70-117 [Materials] Metal is used, probably aluminum for its strength and durability. Some parts might require steel for even more strength. [Forces] The only major forces are those within the engine. These forces would be the result of the fuel combusting and moving within the engine. These forces are equal to the power that drives the bike. [Manufacturing Process] This part is an assembly of many different processes. There would be die casting for the main part. Drilling would be done for several connecting holes. Several parts have been welded on as well [Shape] The shape lends itself to many different processes because it is so complex. No single process could create the engine block as a whole. The side gears and rotating parts would need to be separately made then assembled [Part Complexity] 5 [Function] 
Functional: Takes the fuel provided and turns into in to forward motion, by the use of chemical combustion
Group 11 - Beginner Dirt Bike - GICL Wiki