Hub + chainline question

Unknown
Unknown
edited June 2007 in Road general
Was wondering if anyone knows the answer to the following question(s)

If I'm fitting a 135 mm fixed hub to a regular road bike, what length BB do I need to ensure the correct chainline?

Is it dependent on which I hub I choose?

Cheers

Comments

  • Anonymous
    Anonymous Posts: 79,667
    Yes depends on hub, and crankset. Normally crankset and BB would be bought as a matching pair to give a specific chainline offset (eg 43mm). Hub would also specify a chainline offset which should match.
  • Unknown
    Unknown
    Ah - I see. So if BB and cranks are not matching pair, then chainline is a bit more trial and error etc.
  • monty_dogcp
    monty_dogcp Posts: 382
    Yup, and it's often the case that you have to experiment with different chainsets and BB's to get the right chainline. Many 135mm/SS hubs have a wider chainline of 47.5 or 52mm to give a shallower dish, stronger wheel in comparison to a traditional 120mm wheel with a 42mm chainline - this will obviously need you to move your crank 10mm outboard in comparison to a track/fixed wheel
  • Unknown
    Unknown
    Or space the sprocket?
  • monty_dogcp
    monty_dogcp Posts: 382
    Depends on how much thread is on the hub, but apart from reversing the sprocket - if it has a shoulder, there's often not much leeway if you need to fit a lockring too.

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