I am following along Richard Yot's excellent tutorial on modeling in Modo, but altering the technique to recreate this in Houdini. I've used Alexey Vanzhula's soft boolean plugin for the extensive parts that used MeshFusion in Modo. Some things are actually much easier in Houdini while things like cuts and action center/falloffs are more difficult. Overall, there isn't really a huge benefit or decrement to using Houdini for modeling over Modo at least for this kind of work. I haven't done the engine (final part) yet, but so far, so good. This illustrates the point that one doesn't need another 3D app to do modeling if one is using Houdini. Attached is a wireframe and Mantra render.

Richard Yot uses extensive procedural modeling features in Modo and not surprisingly, these are much easier to do in Houdini (usually in several ways, unlike the limitations in Modo). Non linear procedural features in Modo are pretty unintuitive and one needs to hide a lot of construction steps to make the workspace half way interpretable. The falloffs in Modo are quicker, but an attribute wrangle with a ramp in Houdini is much more customizable. Symmetrical modeling is easier in Modo (edge loops, symmetrical features to edit, etc.). One can sometimes get around this with clip and mirror nodes in Houdini, but not when one only wants to perform symmetrical modeling of a particular feature. Overall, it is much easier to fix and adjust the model in Houdini. In Modo, one frequently needs to do mesh cleanup of errors generated in the procedural modeling.

One major thing that could improved in Houdini is the poly split node. If one invokes the loop cut and wants to make symmetric cuts, one has to do some math. For example, a tube cut at 90% at the top and bottom requires a 90% cut and then a 81% cut, since the edge is shortened by the first cut. There should be a symmetric option. Also when one wants to make several edge loops cuts at once, there is no way to do this. Both these features could be fixed by an updated node or hda. It is only a small issue but nonetheless, annoying.

It would also be helpful to have a snapping feature when one is using the apostrophe key to move the construction center of a model away from the origin. Usually one would want to snap to the orientation of a point, polygon, or model center to mimic a change in action center in Modo.

For those unaware of the Soft Boolean plugin for Houdini, here is an example that is just as good as MeshFusion, in my opinion.

I will post hip file when done if ok with creator of soft Boolean plugin. Richard Yot gave permission to include his methods translated to Houdini in the file.

Here is the finished model, but I didn't spend anytime on texturing (Mari/substance painter etc.) nor even in UV mapping. I didn't try to fix modeling nodes to make it more procedural, but it turned out ok. The zip file is attached if anyone is curious.

The reference image can be found at https://www.barrett-jackson.com/Events/Event/Details/1929-INDIAN-401-MOTORCYCLE-178592 [www.barrett-jackson.com]

Really nice and well done. Also, I don't believe everything needs to be procedural, even in Houdini, so don't stress.