How to Overhaul a Bicycle Hub Gearbox Without Dismantling

Using a bike for short distances helps to save money and is good for health. However, the professional maintenance is quite almost as expensive as that done for a car. You can fix many bike problems yourself. Problems in shifting a hub-based gearbox come frequently from hardened long-term lubrication grease, which will cause gear-changing problems. Before starting to dismantle the hub, try the procedure below, as described. Many hubs treated this way may be usable at once after this procedure.


  1. 1
    Obtain 15 mL ATF (Automatic Transmission Fluid = gearbox oil for automatic-driven cars).
  2. 2
    Lay your bike with the left on an old blanket. The chain-driven side should be facing upward to you as you stand over it.
  3. 3
    Operate the highest gear to get the shifting wire to sit without tension.
    • Hubs with more than three gears may have other positions for lowest tension; see the manufacturer's manual, or you can look online.
  4. 4
    Turn out the petty shifting chain by turning it anti-clockwise.
  5. 5
    Remove it. Place it on a clean cloth.
  6. 6
    Pour the ATF into the hole of the rear hollow axle of the shifting chainlet.
  7. 7
    Wait for 20 minutes for the reaction.
  8. 8
    Repeat the repair steps in reverse. Turn the chainlet in the hole (clockwise) until it won't move anymore.
  9. 9
    Turn it ever so slightly anticlockwise to avoid mechanical damage.
  10. 10
    Connect the chainlet with the shifting wire, mostly a sleeve with an inside tapped thread.
  11. 11
    Adjust the shifting system as described in the manual.
    • Three-gear-hubs will be adjusted by shifting on position "3", as here the tension is lowest.
  12. 12
    Enhance the tension by turning the adjusting sleeve until it is at a very light tension.
  13. 13
    Fix this position now by adjusting the sleeve with the counter-nut. This involves mostly a "ring" with an inner thread.
  14. 14
    Start driving the bike and shift it. Mostly it will work as brand new, as the long-time grease lumps are dissolved. Many incorrectly working hubs have only lubrication problems and are mechanically fine and undamaged.


  • Avoid spilling of ATF or other lubricating agents––the environment will be happy about it.
  • Use oil-proof fitting gloves. It will be better for your skin.
  • In case of dirty, oily hands you can treat them with margarine; after a minute you can wash them with a skin-frindly dishwasher agent. The best agent for severely oily hands is Solopol(TM) paste, a combination of skin-friendly agent with powdered walnut shells for effective and smooth abrasion of dirt (used in German Forces and coal miners).


  • Never pour oily substances in your sink. Use an environment friendly way to dispose of it.
  • Keep these substances out of reach of children at all times.
  • If problems when shifting are still present, a dismantling of the hub should be considered, but doing this in a workshop tends to be expensive. Replacing the complete rear wheel will usually be cheaper, especially when adding a used one in good condition.
  • Rear wheels with a coaster brake need a bit more care.
  • In case of problem with a coaster brake, this must be treated to avoid dangerous situations during actual use.
  • Never use a bike with brake problems!

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Categories: Bicycle Brake and Chain Maintenance