Author Topic: Where is my used oil?  (Read 232 times)

onrbikes

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Where is my used oil?
« on: September 19, 2017, 11:50:00 AM »
So after my tour am in the process of doing an oil change and when I drained the oil nothing came out. Not a single drop even after letting it sit for a day. Its warm here so it’s not the temperature. I got lots of time so wanted to make sure.

I then put the flush through (20ml) and went for a 10km ride. I let it sit for a day and was lucky to drain 5ml out. Where is the rest.

While on the ride I noticed an oil drip on the ground of my hotel rooms in the beginning of my ride. Always on the gear side as that’s the side I use to lean against the wall.

Where did it all the oil go?


mickeg

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Re: Where is my used oil?
« Reply #1 on: September 19, 2017, 04:43:21 PM »
If it was water, there would be 17 to 20 drops per ml.  Oil will be different but I do not know by how much.  (I am sure it varies with viscosity, etc.)  Thus, you likely have several hundred drops in the hub.  If you notice occasional drops on the floor I suspect you would also leave a drop every few km too, which could consume hundreds of drops.

Everything I have read says that you do not need to worry about finding that your Rohloff is not full of oil so I suggest you not worry about it.

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I had the opposite worry on my Iceland trip, I had a huge amount of oil loss during that trip (see photo), I changed the oil shortly before the trip and when I saw that oil loss while on my Iceland tour I suspected that I had a bad seal somewhere.  But eventually I changed my mind on that, now I suspect that much of the oil was pushed out of the hub while on the plane rides (two flights) and the difference in air pressure while flying was the driving force to push oil out.  I suspect that my hub was oriented shifter-side down on one or both flights.

But after my oil change that I did after that trip, things are back to normal, I do not see any evidence of significant loss like I did in the photo.  So, I am no longer concerned that I have any bad seals or anything like that.  I have never even seen oil drops on the floor. 

At home I store my bike oriented vertically in a bike stand, but when I temporarily leave my bike elsewhere it leans towards the left on a side stand.  During my Iceland trip, when I was not riding it I left it on the side stand leaning towards the left side where the oil leakage was.

« Last Edit: September 19, 2017, 04:45:00 PM by mickeg »

Andre Jute

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Re: Where is my used oil?
« Reply #2 on: September 19, 2017, 10:26:08 PM »
Where did it all the oil go?

It stuck to the gears.You can rest easy. As long as you do the oil change every 5000km/3000m or once a year, whichever comes sooner, or some reasonable approximation of these periods, and don't ride the Rohloff through water over the hub, it is lubricated.

I had a period of puddles under the gearbox. Eventually I traced it simply to when the heating in the room where the bike stands was switched on and off by the timer. It hasn't happened for a long time, perhaps because I stopped putting in the full 25ml of four seasons oil and instead measured a more reasonable 15ml.

A certain amount of oil is breathed out by the hub. The oil in the hub is, at least theoretically, open to the atmosphere through a breather hole in the centre of the axle. If you do the math of what you put into the hub as cleaning oil and four-seasons oil, and what you recover of the cleaning and dirty four seasons oil from the previous service, by the time you do the second service there's always some oil "missing". (It also happens on the first service, but you haven't got all the numbers because you can't be certain what the factory put in...) The difference between the static, normative case and the real-live dynamic case of your bike was breathed out through the seals. Refrain from cleaning your hub for a few months and there will be a slick of thin, relatively clean oil, enough to leave a good deposit on your finger if you rub it across the hub.

This breathed-out oil gets everywhere, including on the circumference of the gear housing between the flanges to which the spokes are attached. Perhaps fancifully, I'm encouraged by the image of my Rohloff gearbox proceeding in a halo of misted oil.
Andre Jute
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