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  1. #1
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    Fixing Rohloff Leak

    I have had a Rohloff hub for some time. And as most people who have owned them. I have taken the good with the bad. The leak from the non-drive side was a real pain. So I decided to try something I had done on my Land Rover, and replaced the oil with a high quality grease.

    Now I have all the benefits of the sealed hub without the mess. Has anyone else tried this?

  2. #2
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    Rohloffs don't leak. They just weep oil....



    As they are designed from the ground up as a oil bath hub, I would not recommend running it as a grease hub. The clutch mechanisms require a very low viscosity lubricant to work properly, and we regularly have to thin the oil in the winter (sub-freezing temps) to keep the clutches working. Thin grease in warm weather may actually work though.

    The general consensus (and info from Rohloff) is that if you see weeping from the non-drive side seal, the hub has been over filled with oil, and it usually stops weeping after the excess is lost. It also weeps a bit from the drive side. There is a labyrinth path through the axle to equalize environmental pressure changes, and most weeping comes out though that path, which can be exasperated by lying the hub on its side.

  3. #3
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    Quote Originally Posted by itsdoable
    Rohloffs don't leak. They just weep oil....



    As they are designed from the ground up as a oil bath hub, I would not recommend running it as a grease hub. The clutch mechanisms require a very low viscosity lubricant to work properly, and we regularly have to thin the oil in the winter (sub-freezing temps) to keep the clutches working. Thin grease in warm weather may actually work though.

    The general consensus (and info from Rohloff) is that if you see weeping from the non-drive side seal, the hub has been over filled with oil, and it usually stops weeping after the excess is lost. It also weeps a bit from the drive side. There is a labyrinth path through the axle to equalize environmental pressure changes, and most weeping comes out though that path, which can be exasperated by lying the hub on its side.
    +1
    Check the oil level isn't too high and be sure to keep the bike/wheel upright when stored for any length of time. (If you lay your bike on it's side while you eat your candybar on the trail, not really an issue.)

    I hope you can effectively get that grease out of there.

    Good luck!

  4. #4
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    Ro- Leaker

    I just used a small amount to make sure there was some lubrication left in case I lost too much oil. Not sure if the oil seeps from the left seal or from the holes where the axle plate attaches.

    So far the grease has not caused any shifting issues.

  5. #5
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    So why don't you just buy an oil change kit and R &R the oil and get it up on the dipstick proper, instead of risking junking an expensive gear box?

  6. #6
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    The reason that Rohloff use oil is simply that it is a "returning" lubricant. Grease is not.

    Grease will be forced out of the areas where it is needed and will not return by itself. This renders these areas susceptable to rust and increased friction etc. You will only notice that the grease is not working when it is too late! Grease is also generally too thick to run into and lubricate the bearings of the SPEEDHUB.

    I guarantee that after a short amount of time you will notice a huge increase in drag and the bearings will be shot after a few cleaning sessions where water gets under the seals and into the bearings!

  7. #7
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    Quote Originally Posted by estutjaweh
    The reason that Rohloff use oil is simply that it is a "returning" lubricant. Grease is not....
    Although this is basically true, keep in mind that most IGH are grease hubs.

    The rule of thumb is: grease for bearings (ball or roller) and oil for bushings. The rolling action of bearings will draw grease in. Gear teeth can work with both, but under high loads, the teeth tend to squeegee the grease off the wear surface.

    With gear boxes, oil baths tend to have less drag than grease, and is one of the reasons Rohloff uses it. You loose a bit on the seals though.

    Rohloff uses roller and ball bearing throughout the gears, whereas most of the other IGH hubs use bushings (which also use grease!).

    As I said before, the the main issue with grease in a Rohloff is mucking up the clutch mechs, which can leave your hub freewheeling when it gets cold. There is also the warranty issue, I've been told that there are carbon parts in the hub that can react to different oils, and thus their insistence on using their special oils. Because it is a high $ item, and they have good CS, I won't admit to putting anything other than the sanctioned fluids in my hubs...

    As for running out of oil, you should not be overly concerned. The idea is to wet all the wear surfaces with oil, and whatever remains clinging to the metal surfaces is all you need (for the next ~2 years). Even after a lot of weeping, there is still a fair bit of oil inside. I understand that you really only need about 15ml of the 30ml that they tell you to put in during an oil change.

    I usually put in ~20ml after a rinse, and let it weep for a month, after which it's fine. I do have to clean the disc rotor until it stops weeping - which is a pain.
    Last edited by itsdoable; 04-07-2009 at 06:13 PM.

  8. #8
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    Quote Originally Posted by itsdoable
    Although this is basically true, keep in mind that most IGH are grease hubs.
    ....and this is why they have such a poor working efficiency. The Shimano people could not care less what the efficiency is of their system. Shimano sell these products mostly to customers who would not notice the difference between a high and a low efficiency. This is also irrelevant for the target group.

    Your point about the clutch mechanism is however correct. I forgot to say this. The sliding clutch components are dependant upon the strength of the clutch springs. These are however simply not strong enough to carry out their purpose when there is extra thick grease within the gear-unit which hinders the movement of the components.

  9. #9
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    Thanks for all your advice. It seems that the design of the gearbox itself is impeccable. However, there are leak paths on the non-drive side where the shift mechanism attaches.
    A couple of flimsy gaskets are not up to the standard of the rest of the engineering of the mechanicals. O-rings would be more appropriate.
    I have a BMW 1200GS which again is an engineering marvel, but like the Rohloff has a few glitches ( lumpy idle, crunchy gearbbox ). The Japanese do a much better job on the details.

  10. #10
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    Quote Originally Posted by estutjaweh
    ....and this is why they have such a poor working efficiency. The Shimano people could not care less what the efficiency is of their system.
    Is this true? On the sheldonbrown site, the newest Alfine, with a triple roller clutch, is said to have improved efficieny.

    http://www.sheldonbrown.com/harris/shimano-nexus.html#3

    John

  11. #11
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    I have used internal geared hubs since the 1970's
    They all used grease and I rode them hard without any problems.
    I figured I would rather have enough grease in my rohloff instead of constantly not knowing how much oil I had, since I seemed to lose all of the oil in 100 miles anyway. Your suggestion seems O.K. if I didn't lose so much oil.

  12. #12
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    I have an older hub, about 3-4 years old, it did have some leaking. I took it to Neil with Speedhub USA in Oakland, CA. You can call him at 510-868-1777 to get specifics. He's found some of the older models don't have plug/set screw under one of the pieces which seeps oil then. He put in one and no leaks for me now. Hope that helps.

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