I'm impatiently waiting for Surly to deliver my Ogre so I can complete my BBS-02 build. I ordered the 44-tooth chainring available from EM3EV (the smallest they sell) because I have a lot of steep hills in my area. I noticed Court's recent review of the BME Shadow, in which he says:
A quick check of BME's website shows that BME's other bikes use smaller front chainrings with cassettes in the rear. I've read that anything smaller than, say, a 42-tooth chainring on a BBS-02 creates chainline issues because the stock Bafang chainrings have an offset profile. A standard chainring would lack this offset profile. In short, my question is whether any special adaptation is needed to adjust the chainline when using a smaller chainring on the BBS-02?the other BMEBIKES models come with an aftermarket Raceface NW sprocket in the front that’s a smaller diameter with fewer teeth.