Object created by joining several objects doesn't rotate uniformly consistently

Aloha. An object I created by joining 3 objects doesn’t rotate uniformly consistently. I tried clearing and applying rotation of individual objects and joined object to no avail. I’ve actually had this problem with another object a while ago which I had to work around without a solution. I uploaded clip of defective object in scene. Notice the large gear stops rotating as shaft and smaller gear continue.

Any ideas? Thanks.