Down in the workshop people ask us lots of questions. The latest thing that has come to mind is how to get chain tension on a frame with vertical dropouts. You might want to do this for single, fixed or hub gears. I’ll list them in order of complexity.

Use a chain tensioner, that could be an old rear mech (Dura-Ace or Record if you like) or something made for the purpose by Rohloff or Surly to name but a couple of brands. It almost goes without saying that this is for single & hub gears only. The Brompton Fixie has a chain tensioner but it does have some perceptible ‘lash’ in the drivetrain when you pedal backwards.

If you have something against tensioners, or they’re just not going to work for you then try looking for the ‘magic gear’. Apparently 2:1 works on all Specialized Stumpjumpers, you just have to change your chain when it gets a little worn. Same will be true of other frames.

Use a half-link in your chain (or a whole chain made of half-links) it might allow a different combination just works.

Cut your dropouts off and have a framebuilder install some track-ends, this’ll solve your issues for good

Eccentric axle hub. If you have a really nice paint job on your frame and don’t want to cut anything off you might try the White Industries ENO hub, it can either take a fixed cog or a screw-on freewheel and has an eccentric axle that allows you to tension the chain.

If you have some nice carbon fibre road wheels that you want to re-use into your fixie project you can use the Surly Fixxer to replace the Shimano brand freehub with something that allows a track cog to screw on.

Now if you want to use these newly fixed wheels with your nice frame you could use a Trickstuff Exzentriker excentric bottom bracket that fits in a conventional bottom bracket shell. As I understand it this uses an external bottom bracket standard meaning that your pretty square-taper track cranks will be unsuitable

Lewis