it's been over 12 years since these showed up anywhere, the Von Dutch engine studies, but they just were auctioned by Bonhams

I've never seen these on the internet anywhere since I came across them in 2006 on http://www.arielmotorcycles.com/vond.htm which is still up, and hasn't changed a bit. If you want to see how bad website design was a dozen years ago, there aren't many website that didn't evolve and advance when the tech came along, but that site certainly hasn't

https://silodrome.com/engine-designs-von-dutch/
http://www.bonhams.com/auctions/24509/lot/8/?category=list&length=10&page=1
http://justacarguy.blogspot.com/2006/12/von-dutch-expert-mechanic.html