On Sunday I serviced my Rohloff with 25ml of Cleaning Oil -- and on Wednesday got 30ml back after the syringe hung down from the drain hole for two days. Here's the proof:
Hallelujah! 30ml of oil drained from Rohloff Speed 14. Unfortunately, there were special circumstances.
Let's do some quick math here. Inside the Rohloff there should be the 16ml of All Season Oil that I put in at the previous Power Service last year, plus the 25ml of Cleaning Oil I put in on Sunday, total 41ml less what dropped on the paper I put on the floor, in any event say at least 37ml (that's a different calculation: 12ml of All Season Oil that sticks to the gears plus the 25ml of Cleaning Oil, with the difference of 4ml presumed misted out or dripped out of the tube after I detached the syringe). However, experienced Rohloff cyclists know for a fact, and I do too, that if you get much oil at all out after putting in 25ml of Cleaning Oil, you never get even the whole 25ml of Cleaning Oil back.
Okay. What happened here? Special circumstances is what happened here. The year before the Chinese virus, Covid-19, wasn't too great for cycling in Ireland and my pedalpals kept dying or breaking their bones in golfing falls, so my total distance was a miserable 600km. Then came the pandemic and it soon became obvious that the mandatory mask steamed up my spectacles every couple of seconds so that I couldn't even ride into the countryside to the permissible radial limit from my house. To cut a miserable long story short, I hardly cycled for the two years of the pandemic. But I still serviced the gearbox on the once-a-year schedule, and I've been getting more and more oil back out, and less and less black. But this is the first time I've seen somewhere near what the math which so upsets newbies misleads us into thinking should have come out.
Okay, let's make some new math to explain what we're seeing. Last year, after servicing the Rohloff with Cleaning Oil, and draining the Cleaning Oil, and filling with 16ml of All Season Oil, there was, at the moment I finished the service and screwed in the new stud, the following in the Rohloff:
1. A mixture of whatever old All Season Oil wasn't washed off by the Cleaning Oil, with some Cleaning Oil sticking to surfaces, minimum together 12ml.
2. Possibly a small amount of dirty mixture not fully extracted, maybe 2ml or 3ml.
3. 16ml of All Season Oil I put in.
4. Can we all agree this is a minimum of 28ml or perhaps 30ml in the gearbox?
Now the bike stands for all of last year and the first few months of this year, except for a few very short rides to the shops, very likely a few tens of kilometers. The only time the gearbox moves seriously is when I spin the wheel with the motor so the oil and whatever scarf remains in the box doesn't settle in one place and get stuck there by dried oil. Nothing is flung out and what is misted out doesn't settle on the tiles on which the bike stands, so I can't tell how much has misted out. That has to wait for the next service, this one, as has an assessment of how much water vapor entered the box.
Now let's calculate what I got back this year in "dirty" oil for disposal. There was, by our last calculation, 28ml or perhaps 30ml of various oils in the box a year ago, and on Sunday last I added 25ml, call the total 55ml and a couple of days later drained 30ml, or say 32ml to allow for spills. It seems unlikely to me that anything misted out or condensed inside the gearbox in this brief period when nothing about the heat cycle around the bike was changed. Okay, here we go:
1. 55ml total presumed in gearbox.
2. 32ml taken out.
3. A further 12ml sticking to gears and inside structures and walls of the Rohloff.
4. So we have to account for 55 - 32 - 12 or 11ml that misted out plus some amount for water condensation from the ambient air, which I'm planning to ignore unless someone wants to put a number on it.
Finally, unless someone finds a logical flaw, we have a handle on why so little comes out of a Rohloff after a 5000km/3000m of use or one year of even near-zero use.
About 11ml is the minimum annual "missing oil" from the Rohloff Speed 14 even with no use. With use it seems to me inevitable that the "lost oil" will amount to more than 11ml.
***
We're not talking about very dirty oil but that the cleaning oil should become at all darker when cleaning an essentially unused Rohloff raises the obvious question: Why? First of all, the Rohloff HGB isn't sealed against air, which carries water vapor, which
will react with oil and discolor it. Second, the Rohloff is made of aluminium, which also reacts with oil. Third, there's steel inside the Rohloff which is subject to rust. Fourth, you never get all the dirty Cleaning Oil out of the Rohloff, because it too sticks to the gears, complete with whatever dirt it picked up from easier services, so at the next cleaning cycle, even if the bike was not used, the Cleaning Oil extracted will bring at least a little "heritage dirt" with it.
