Alot of motorcycle models I have seen start from the 3D VRML collection, which i've gone and lost the link to. Found the same models on another site in various formats
3D CAD Browser - 3D Model Preview - Harley Davidson US Army (1940)
Is that the type of thing? (cept in paper)
Edit: found the original site for these models :-
http://www-roc.inria.fr/gamma/download/