hub spacing/chainline advice.

Posted on
  • I have started to get together a new bike.

    I have bought parts for a wheelbuild first, with my rear hub being 120mm spaced.

    I am now on the hunt for a frame.

    I have found something pretty nice, but it has 130mm spacing. My hub axle is pretty long and I do have a bunch of washers. But I was wondering, if I run a 120mm intended hub in a 130mm intended frame. Will it give me grief with chainline?

    As I can understand, that it would cause the cog to be 5mm more inward than intended.

  • Nope, you pack on the outside of the chainline, not the inside, provided you put equal amounts each side, you will have not problems (well none caused by that anyway).

    Handy little (god I need to get photoshop at work) paint diagram, 120mm, 130mm and 100000mm rear spacing

  • You might have a chainline issue because yer cranks need to clear 130mm spaced chainstays.

  • small ring small cog would be desirable in this case

  • Is this frame made from steel?

  • get a long straight stiff ruler, put it flat against your front chainring and see where the chain should be relative to your rear cog.

    The rest you just adjust to get it right, washers and so on, self explanatory really. Failing that you get a proper BB for the job, either bigger or smaller depending which way you need to go if you don't mind playing around with the Q factor.

    you might need to re-dish your wheel if it's a tight frame.

    edit] if your about to build your wheels, work out all this before you start, maybe a proper sized hub will prevent all this hassle, so your cog can sit directly in the chainline by default, no dishing or anything.

  • You might have a chainline issue because yer cranks need to clear 130mm spaced chainstays.

    Crimp the stays, problem solved. Or if your nervous about crimping your stays, ride to bike shop, 'Please crimp my stays', once again, problem solved.

  • tweak the frame, tie a piece of string to the left rear dropout loop it round the head tube and then in the same place on the right then very slowly take the 5mm out each side. and check with a rule that the distance between the string and the seat tube is the same.

  • Wow, what a bunch of different answers.

    In this case, I like gizmonds answer & illustrations best.
    Im going to believe that is accurate for now, as it means I dont have to do anything!

    Plus Id be running a flip flop in any case, so it wouldnt make sense to dish it one way.

    I take it, "crimping" means bending the stays/dropouts?
    Id like to avoid that at all costs, as the reason I dont have a bike is because I snapped the chainstay dropout.

    Im planning to buy the correct BB, I expect itll have to be the smallest one available.

  • Chapters 5,6, and 7 i've learned a fair wack off these vids, ......i think.
    http://www.fixedgeargallery.com/columns/bobgarage/indexb.htm

  • Post a reply
    • Bold
    • Italics
    • Link
    • Image
    • List
    • Quote
    • code
    • Preview
About

hub spacing/chainline advice.

Posted by Avatar for DFP @DFP

Actions