In my work as a motorcycle mechanic I encounter some kardan driven bikes. Part of maintenance is changing the oil on the final drive kardan part.
The drain plug is located almost directly over the wheel, and often the last drips of oil tend to fall on the tyre which results in having to clean everything up to avoid a slippery tyre for the customer.
A simple solution would be to just make a tray that catches the oil before it can drip on the wheel.
The Design :
Printed it in ABS, and it should work. As soon as I'm going to use it, I will post some pictures and let you know if it works as expected or needs some tweaking.