Originally Posted by sebby64

In colder conditions the derailleur moves to the high gear on its own, and the chain does not move back to an easier gear ever. I will start my ride on gear 3 and within a minute it will go to the highest gear and stay stuck until I get down and fix the chain by hand. But then a minute later it will get stuck in the highest gear again.

When I try shifting to lower gears the derailleur moves slightly forward but not as much left as it should. Even switching to the lowest gear does not move it enough to fix itself.

Also thanks for the terminology correction, I'll edit the original post.