pic: Bike Cim + 56 mm gearbox

[Dan Zollman]

I would avoid leaving parts unconstrained because I don't know what would happen if someone else tries to use the files, or if the animation team would import it into 3dsMax. I could be wrong; maybe the parts stay in the right place.

If Solidworks lets you do this, at least ground all the assembly parts. In Inventor assemblies, parts can be grounded, which means that they're locked into a certain position relative to the origin and axes.