Boxerworks.com

I'd never heard of this before. Nardi was modifying WW2 military surplus R75 engines for use in road racing cars: http://thevintagent.blogspot.com/2013/0 ... acers.html

New to me too. BMW made up a few bikes with those engines after the war. They were limited in cc by the post war treaties, so they sold them "under the table" to people with some money. I owned one for years and it was fast. The inside of the engine was quite nice, as it had been worked over.