# [Japt], 6 bytes

    ²é ¤øU

Saved one byte thanks to @Shaggy

[Try it online!][TIO-juvfm31q]

            Implicit input, stored in variable 'U'
    ²       U+U, "abcabc" -> "abcabcabcabc"
     é      Rotate 1 char to the right "abcabcabcabc" -> "cabcabcabcab"
       ¤    Remove first two chars, "cabcabcabcab" -> "bcabcabcab"
        øU  Check if U is in the above


[Japt]: https://github.com/ETHproductions/japt
[TIO-juvfm31q]: https://tio.run/##y0osKPn//9CmwysVDi05vCP0//9o9cREdR0uIAmhkpIhCMKBioEYsQq6uUEA "Japt – Try It Online"