Originally Posted by
swim
and my chainwheel is quite large, but it's welded to my crank arm, so i'm not switching it out just yet, but it has 52teeth, so i should be running a 17t cog with the 52t chainwheel?
To calculate gear inches I'd need to know your crank arm length, rim size, tire size, as well as chainring teeth #. That calculator I posted a link to will help you make the calculations based on your setup.