Upgrading components: 9-Speed to 10-Speed, going to 105 or Ultegra (Shimano)
I currently have a 9-speed road bike using Sora and Tiagra(rear) derailleurs. If I wanted to move to a 105 or Ultegra, they are meant for 10-speed, would I have to change out other parts like the crank or cassette to accommodate?