Thanks a lot.
Its not too bad a leak. I cleaned it all up and went a wee 40 k spin, on a nice dry night and no more has come from it. Its obviously pretty slight.
What you saw was most likely the change of the seasons. A Rohloff gearbox is by deliberate design not airtight. Those paper seals are not a symptom of cheap design but a deliberate air/oil interchange. A Rohloff is supposed to "mist out" through the seals if the change in air pressure gets too big to equalize through the vent hole in the axle. Without some way of breathing, including "overflow" breathing a few times a year for big changes of temperature and air pressure, the air pressure building up inside the hub could drive off the layer of oil on all the gears on which the hub really depends for its longevity. It's not likely to happen except under really extreme circumstances, but Bernd Rohloff designed his hub to be used only in extreme circumstances; our comparatively light use is just a fortunate happenstance.
I keep my bike in heated space and every year at the beginning of the winter and the beginning of summer there is an actual puddle of oil under it, which frightened me sh*tless the first time I saw it, but it's just an extreme form of the same thing you see, because I always put in the full 25ml of oil in the individual oil kit that comes with a syringe, rather than the adequate but tricky 15ml the guys with bulk oil measure out.
You can see the mist of oil sometimes on very warm days on hard hills as fine droplets on the outside of a recently cleaned hub. The toothbrush guys, like Dan, probably miss it, but the more casual cleaners like me notice at the once- or twice-yearly wipe-and-dash that there's a buildup of oil on the outside of the Rohloff. It's natural, a function of how it works. Even if your hub appears clean, wipe a spoke near the hub with a tissue and, unless you ride in a place with loads of road/exhaust grime, you should be able to just niff the distinctive Rohloff Oil smell on the tissue. That's the mist of Perfume d'Rohloff.
Generally speaking, a Rohloff is a piece of German agricultural machinery; it's a mistake, but a natural one, to regard it as an heirloom of fine jewelry. My rule now, in my four year of use, with a Rohloff that has outlived all my Shimano internal gear hubs, and as a member of various groups where we probably hear of every Rohloff failure ever, including all the false alarms, is this:
If your Rohloff ain't actually broke and not working, it ain't worth worrying about.A good corollary is: If in doubt about your Rohloff, ask on the forum. Someone is bound to know.
Andre Jute
