Yeah, yeah, I know there is a different forum for this. Hipsters scare me though. I think it is the ironic facial hair. It could be the lack of bathing too. Either way, I'll stop before i offend most every one.

Anyhow, my commuter is a fixed conversion with vertical dropouts. 46/18 is too slack. 48/17 is too tight, although maybe in 3-6 months the chain wear will make it acceptable.

So my question is does adding a tooth to the cog pick up more chain slack than adding a tooth to the front ring? Or visa versa? Or is it the same? I figure there is an easy answer instead of pulling out my protractor and compass to do some serious geometry. That nightmare ended in 9th grade. I choose not to do any more.

The reason is it will be $50 to buy a 47. So will a 47/18 have more slack than the 48/17? Will a 47/17 be tighter than the 46/18? But if all things are equal, the $50 will go for beer. Or something.