Your wheel must have an aluminium alloy rim in order for Fliiiight to create resistance. Disc brake compatible wheels typically have narrower rims, but in our experience most still create plenty of resistance for a good workout with Fliiiight. A particularly light and narrow rim may not be a good fit for a powerful rider in SIM mode. In ERG mode, always using your highest, fastest gear will help you achieve an appropriate amount of resistance.
Make sure to check your individual wheel for the presence of steel pins. We recommend you source a compatible disc brake wheel before purchasing Fliiiight, as these wheels tend to be more expensive.