At one point I was thinking to use the 98CC Villiars engine that Harry76 and Cam NZ are using for their builds. In following their threads I saw that modifications had to be made to the engine crankshaft and then make up a jackshaft, etc. and realized it was more complicated that it first appeared, which is fine if your are able to do those things. I'm not. I have just simple tools and I am no machinist. Then Fasteddy bought a model 1932 Fitcher Sachs on ebay and it looked perfect. Sachs of Germany made a million (hundreds of thousand anyway) of them to supply the many motorcycle companies in Germany before and after WWII. They are not industrial engines made for something else, but were designed for heavy bicycle frames and light motorcycles. They were concerned with weight, power and reliability. Their engine was so good it cornered the market in Germany. It is made of aluminum alloys, has 98 CC displacement and a built in lighting coil (Bosch). Like a Morini, it is compact with quality materials and beautiful engineering. The two speed transmission gives it quick low range and hill climbing power and the higher range capability for smooth cruising. Clutch is manual and wet bath, as I understand it. A shift lever changes gears. The reputation is that they were bullet proof which is why they cornered the market. They were made from 1932 into the 1950's. In a few more weeks Steve and I will be at work on our Indians and will have these engines in hand. I can hardly wait. Mine will have my canoe sidecar and I believe this engine will be capable of pushing the Indian with an adult passenger in the sidecar. No, I am not a salesman for Sachs. Ha! Just saying, that maybe instead of looking at industrial motors designed for other purposes, it might be worth a look to see what motors designed for light motorcycles are out there and available. You might find your perfect motor for that board tracker right in Oz and maybe for less money than you imagined. For my Indian I have no modifications to make to the engine. All I need to do is set up engine mounts on the frame (I have seen both welded and bolt on mounts for these), purchase a MM hub adapter and sprocket of the right size and that's it. No belt drive, no jackshaft and no having the crankshaft modified in a machine shop. Simple is good.
SB