Rear drive leaks
Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models
When I first restored my Ambassador, I replaced the large inner seal (MG# 90407085) in the rear drive as well as the two gaskets (MG# 12350700) that are sandwiched between the flange and the rear drive box.
After a few miles, I quickly realized that this did not solve all of my problems. So I also replaced the small outer seal (MG# 90403850). During both my seal replacements, I was careful to clean and polish the mating surfaces.
But I was still getting stuff flung all over my newly polished rear rim (and on to the tire, which is less than safe!). When I parked, nothing leaked on the ground, but there was definite evidence that something was leaking.
I brought this troubling evidence to my Dad and he asked a very good question:
Are you sure it's oil?. Up to this point, I had assumed it was, not even thinking about the possibility that it might be grease.
Sure enough, it was grease. I removed the rear wheel to discover that the grease I had placed on the splines where the hub (MG# 12633200) meets the rear drive (MG# 12351400) was getting heated up and flinging out all over my rim. When I was indiscriminately slapping regular wheel bearing grease all over the splines, I had not anticipated this problem.
So, I cleaned up the mess and used Amsoil Fifth Wheel and Open Gear Compound. No more leaks and no more messy rear wheel!