What makes a track bike? Big frame, Steep head angle and tiny clearances
What makes an Mtb? Small frame, Slack head and and big clearances
The brakes/gears/tyres/saddle make little difference, it's frame geo that you've got to consider to begin with, it's the one thing you cannot change and it's the major thing that's wrong with your off-road-pre-cursa idea.
Unless you want to ride towpaths. There's many different levels of off-roadness
What makes a track bike? Big frame, Steep head angle and tiny clearances
What makes an Mtb? Small frame, Slack head and and big clearances
The brakes/gears/tyres/saddle make little difference, it's frame geo that you've got to consider to begin with, it's the one thing you cannot change and it's the major thing that's wrong with your off-road-pre-cursa idea.
Unless you want to ride towpaths. There's many different levels of off-roadness