The most reasonably priced component used on the Kdx250-b2 Kdx250 1982 Usa California Canada Gear Change Mechanism ('82 Kdx25 is the Bolt 6x20.
In this schematic the "Pawl,ratchet" is used most often.
The Gear Change Mechanism ('82 Kdx25 assembly is constructed from several parts from which the Ratchet,change Drum is the most expensive.