The series is 98 episodes long. Here is a partial list of the initial episodes to give you a taste of the classic Shocker kaijin the Riders faced.
The ultimate finishing move, contextualized by the mechanical grunts and tactical shouting of the actors. Kamen Rider 1971 - 1973 -English Subbed-
Now a grasshopper-themed cyborg superhero known simply as Kamen Rider, Hongo uses the very powers Shocker gave him to battle the organization and protect humanity. The series is 98 episodes long