• Potentially very dumb question exposing my lack of knowledge...

    I've cobbled together a budget 1 x 12 TT setup with bits that shouldn't (officially) work together. The good news is that the shifting actually seems to work fine, apart from when I shift to the big cog on the cassette and it drops the chain. Now I hope not to have to use this too often, but it would be nice to know I have the option if there's ever a half reasonable hill.

    It turns out I completely ignored the whole chainline thing, and the chainring is now sitting too far away from the frame, causing too great an angle when in the big cog, pulling the chain off. As it's a GXP setup and there are no spacers being used on the BB, I saw no way of bringing the chainring in at all. I figure I have some options:

    1) As pictured - I put the chainring on the other side of the spider, then gradually move it away from the frame with GXP spacers. this is what I have done in the images below and I don't feel confident about it for some reason. Apart from the aesthetic impact, if the chainring isn't sat in the 'lip' of the spider, will there be too much force on the bolts? I guess that's what happens with inner rings anyway? It seems to work, but am I setting myself up for disaster? (I know the bolts are backwards).

    2) Get a chain guide (would prefer not to do this re buying more things).

    3) Get a chainring with offset (would prefer not to do this re buying more things).

    4) Give up and go 2x.


  • looks like a "normal" toothed ring to me, they tend to drop the chain when you ride them very cross-chained. most folks would use a narrow-wide chainring for 1x12 that "holds" the chain a bit better at agressive angles, bc the teeth are shaped more sophistically. I don't think your bolts will shear off.

  • don't know how big you need the ring but this is pretty reasonable https://www.ebay.co.uk/itm/155400374057

  • Stick the FD back on and use it as a chain catcher?

  • You spaced out a road GXP BB? I mean....talk about asking for trouble.

    You've answered your own question really. New NW chainring or a chain catcher. How you'll fit it to that without a DIY mod, no ideal. Just get a narrow wide chainring.
    You can get direct mount ones to work on that chainset with 3mm or 6mm offsets depending on frame.
    It's what I did. Worked a charm and never dropped a chain.

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