Computer simulations reveal the unique conformation of or erythro diisotactic polynorbornene, a polymer with numerous important applications in microelectronics. While previous simulations suggested that this polymer adopts a helix‐kink morphology, the results presented herein indicate that the reversal of the helix symmetry is the origin of such kinks which cause a transition from a rigid‐rod conformation to a random coil with increasing molecular weight. An RIS model was developed that accurately predicts the unique conformation of this polymer. This model predicts a rigid‐rod helical conformation that eventually transitions to a random coil at a degree of polymerization of approximately 500.