I'm sure by now almost every engines been made as a model. As the old saying goes " You have to walk before you can run ". I just finished my first Elmer's engine so It would be way down the road before I'd consider trying a build like that. Plus I need to learn alot more machining techniques. I am well versed in the full sized engines particularly the Airheads from the early 60's thru the end of production in 1995. Currently I'm rebuilding a 1965 R50/2. And since the engine is completely reassembled and on the work stand I started looking at it from a different perspective. It wouldn't be too hard to scale this down to a model size. The oil gallies would have to go and some tubing with nozzles would suffice. Just wondering if anyone has built, or knows someone that's built a BMW style motorcycle engine. Just a random thought. Roger