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By using custom formatting and load / save routines ( sometimes included in third-party DOSes, see below ), all of the mechanically possible 40 tracks could be used.

The reason why Commodore decided not to use the upper five tracks by default ( or at least more than 35 ) was the bad quality of some of the drive mechanisms which did not always work reliably at the highest tracks.

So by reducing the number of tracks used and thus capacity, it was possible to further reduce cost-in contrast to Double Density drives used e. g. in IBM PC computers of the day which saved 180 kB on one side ( by using a 40 tracks format ).

The 1983 Apple FileWare minifloppy drives used double-sided media, higher track pitch, and variable motor speed to achieve a storage capacity of 871 kB, or 435 kB per side.