This issue has persisted since Forza Motorsport 3. The Fikse FM/10 wheels in Forza have an inaccurate and very low quality model. It seems that they were modeled for a larger diameter than they were ever offered in.
Hello,
In some cases bugs will not be fixed due to a variety of reasons such as the feature becoming obsolete, the feature is currently intended and working as expected, or a risk of creating larger issues when attempting to fix
Thank you,