Hi I’ve just converted to Single speed and loving it. I want really clean lines so I’m using half links rather than a chain tensioner.

How tight should my chain be?

you need about 3cm of travel up and down at the center point between front chainring and rear sprocket to account for the sprocket and ring being slightly off center

Neither your front ring or the sprocket will be perfectly round either, so feel the tension in the chain as you back-pedal (i.e. push the pedals round backwards with your hand and use your hand and an oily rag to feel when the chain is tighter) and make the adjustment for the chain’s tightest point. Otherwise you risk having odd tight spots, which may shorten the life of your bearings.

: P

You can get off with quite a bit of slack if your chainline is spot on and if your frame does not have flexy chainstays.

Not too tight that they won’t spin backwards freely. Tight enough so that it wont get bounced off. I think that’s usually 1-2cm of up/down play.