Note the very large diameter of the bearing retainer that is just inside the right side of the hub.This type of design is common to internal-gear hubs which do not have a thread-in right ball cup, and discourages use of oil lubrication because the oil would run out. The Elan goes one step further with grease lubrication: manufacturer's instructions are not to disassemble the Getriebe and so, not to clean and relubricate the internal parts. If there is a problem anywhere in the Getriebe, it must be replaced in its entirety! Perhaps one reason the gears are so massive is so they will need replacement less often.