Soft Vs Rigid C Collar What Is The Difference Between Rigid Mount Vs Rubber Mount Harley?

What is the difference between rigid mount vs rubber mount harley? - soft vs rigid c collar

Newbie here and looking to buy your first bike is a Harley. I watch the queue is a quiet night and saw the specifications which have a rigid engine. What does this mean? How do you want? Is it good or bad? I searched the site for information on the Harley, but there's really nothing for someone like me who know nothing about em other than that I have a wish. Thank you for your help:)