I knocked a hole the size of my little finger tip in the aluminum cam cover on my Goldwing while on a long long trip. It's on the side of the engine and has lots of oil in it. I cleaned it with gas from the tank and patched it on the side of the road with the JB Weld epoxy I always carry with me on trips. I let it cure for an hour and continued on with my trip. When I learned how much Honda charged for a new cover, I decided the patch was good enough. It has been good enough for tens of thousands of miles.
I also have patched four radiator leaks on various of my motorcycles including that same Goldwing and two KLR650s.
So, my recommendation is to patch it with JB Weld and consider it a permanent repair. I just use the regular JB Weld and it works fine , but you can get some JB Marine Weld for aluminum.
You might want to drill a small hole at each end of the crack to keep it from running any farther.
Last edited by GoMotor; 07-05-2016 at 11:55 AM.