Say,.. nice Bike
am I required to uv unwrapp the entire model?
If you have texture maps used in any part of the model then that part should be UV mapped, whether you use a standard mapping, like Box, cylindrical, spherical,.. etc, or use UV Unwrapping is your choice, but most Figures and clothing use Unwrapping to create the UV layout’s, (which are available for most products) so that the users, or other published artists can also create “alternative” texture maps.
For the parts which use shaders,. then these should also have some type of UV Mapping applied, to enable texture based shaders to be used.
Basically all models you create in any 3D program should (By default) have some standard type of UV mapping which is automatically applied to them,.. when you create them.
If you later want to alter that default UV mapping, or change it to UV Unwrapping,.. that would depend on the shape of the model and how you want to texture it.
Depending on how the model is made, and what you think should be changeable (tank colour and details) ( seat colour and details) then these areas should be UV mapped, and Unwrapped and they should be separate parts, and use different shading domains, so that they can be textured differently or Hidden,. using alternative maps or shader options.
You’ll also want to add some Spokes to those wheels for a much smoother ride
hope it helps