Greetings and Happy Holidays to all. I have some questions on German motorcycle painting. I am building some of the GreatWall/LionRoar motorcycle kits, both the Zundapp KS750 and the R75. In looking at the box art for kits #L3524 and L3510, both are painted in overall darker grey, but in both box art photos, the engine is an aluminum color, as if the block and the ribbed cylinders and cylinder covers were all made of aluminum. Is that actually the case? Was the engine block, the two ribbed cylinders, and the cylinder head covers all made from aluminum? If so, it will simplify my painting procedure at the end. On the box art for both kits, it sure looks this way. If so, then I just paint the rest of the motorcycle the prevailing color of the time (either dark grey or dark yellow), and the engine would simply be the aluminum color. But since I know very little about German motorcycles, I have no means of ascertaining that assumption. Can any of you German motorcycle experts help me out?
Regards,
Mark Pinson

The BMW had an aluminum engine at least.
You may want to read this for some more in depth knowledge about how to restore one of those beasts:
http://www.bmacinc.com/wp-content/uploads/2017/11/1942-BMW-R75-WH-Restoration-Project.pdf

I am fairly certain that the Zündapp had a mostly aluminum engine, in the later stages of the war the cylinder head covers were made of pressed steel sheet instead of aluminum to save on valuable metal ....

/ Robin

Robin,
Greetings again. I believe you also helped me with a BussingNAG question several months ago.
Thanks for the help. The pictures almost identically matched the box art. It appears that the cylinder horizontal extension is a two-piece affair. The cylinder for the piston appears to be cast iron (sensible enough), while the outer part containing the valves, cam, and rocker arms is aluminum(again, sensible enough). The block and cover for the transmission are aluminum, so, in essence, mostly aluminum. There are several pieces painted black in both your photos and the box art, and the cylinder casting is also painted black (undoubtedly for corrosion resistance).
So, the box art matches the photos you sent me. Also begs the question if LionRoar saw these photos and did their box art off the photos, or if this gentleman used the box art to get his paint right? Whatever.
It was also nice to see the up-close photos of the wiring and carburetors. On the LionRoar kits, they omitted the spark plugs on the top of the horizontal cam/valve head. They did include the photoetch plug wires, just no sensible place to put them on. I added small, cylindrical styrene rod to be the spark plug/cap. This just gives a nice up-close shot.
The LionRoar/GreatWall kits are not for the faint-of-heart or people that dislike very small parts. The cylinder/cam ribbed heads are especially tedious to get cleaned up after getting the glue seams out of the ribs. But just like the gentleman with the real R75-nobody ever said it would be easy.
Thanks, again, for your help, my friend.
Regards,
Mark Pinson