Right. This isn't my first oil change. It's the second. I reported on my first change on this board. This one was less fraught. I had some time to think.
This time:
1. Both oils that came in the official Rohloff kit, from Bike-Components.de in Germany, were clear. Both bottles were filled a fraction short.
2. My hub definitely leaks oii. It is always dirty. I use a chaincase, so the oil cannot come from the chain, it must come from the gearbox. I wipe the box only once or twice a year, though, so one doesn't know how often it leaks.
3. I sucked up about 20ml of cleaning oil and inserted it into the hub without spillage.
4. Sucked out 15ml of air.
5. Rode the bike 3km in 3rd and 5th gears to engage all the planetaries and make sure the cleaning oil reached everywhere.
6. Let the bike stand 15 minutes, recommended time, with syringe screwed in and hanging down. This is definitely not long enough even out in the sun on a warmish spring day.
7. Extracted 25ml of old oil and cleaning oil, plus a good few drips afterwards, call it another 2-3ml, over another 3/4 hour.
8. This squares well with the history of this box. Those with good memories will remember that to be certain that enough oil went in last time, I extracted the clean oil again, and it came to approximately 10ml, of which at least 8ml went back. This in addition to whatever stuck to the gears, which by convention is 12-15ml. So, 20ml of cleaning oil in, perhaps 28ml of old oil and cleaning oil out, plus a little something that sticks to the gears -- leads me to think the misting and/or leaks that cause a dirty gearbox don't amount to a lot of millilitres. I'm not planning on sending my Rohloff box to Germany and looking like an idiot for a little oil on the outside of a hub gearbox designed for off-roaders.
9. Sucked up 22ml of clean oil and inserted at least 20ml of it, the rest wasted in a small drip and stuck in the tube. Drew off 25ml of air.
10. We've heard reports of other people forgetting the sucking up of air at each stage. I too forgot the first time I did this. I'm just wondering if differential air pressure causes
extra misting, if my box will stay a bit cleaner now that I've remembered the air equalization step.
SOME OBSERVATIONS:
1. Service at 15 months and 2100km. Bike is kept in centrally heated space, ridden on dry hardtop roads, hardly ever out in the wet; that Rohloff box has never been thoroughly wet, never mind submerged.
2. A Rohloff may be a low-service item, but as modern hub gearboxes go, all the others are
cleaner than the Rohloff. For cleanliness, the cheap Shimano Nexus hub leaves the Rohloff for dead. (I have two bikes with Nexus gearboxes as well. One of them broke under 5K miles, so cleanliness isn't everything...)
3. Maybe for bikes
much harder used than mine, the service interval of one year is fair.
4. But, frankly, looking at the oil that came out of my gearbox (not black at all, more a sort of grey), and rubbing it between my fingers (smooth, zero grit), I think Herr Rohloff is covering his ass, as our American cousins say.
5. I think a Rohloff hub, especially one not used offroad, not ridden through streams, not powerwashed, can go more than one year between services, and if low mileage, probably several years. Someone published a letter from Rohloff here the other day which makes it clear that what the one-year service interval is about is ingress of water. I realize condensation from temperature change is as dangerous as riding through water above the hub and powerwashing, but who with a touring bike -- which is most of the members of this forum -- actually commits such outrages on an expensive bike?
6. For less than 20 Euro a year, and a couple of hours of my time, I'm not going to lose the super guarantee Herr Rohloff gives, so I'll keep the service schedule myself. But I definitely think the recommended interval is more about the guarantee than the longevity of my Rohloff box.
Andre Jute
http://coolmainpress.com/andrejute.html