Hi Zabi - it isn't a step-by-step tutorial, but there was some discussion on modeling a bike frame in this thread: http://moi3d.com/forum/index.php?webtag=MOI&msg=1012.1

You may find that useful.

You might also try checking on the web for tutorials that are based on other modeling programs like Rhino, if you can find some probably the same strategies can be applied to modeling in MoI as well.

- Michael