Joined: Jul 2002
Posts: 40,863
Likes: 3,116
From: Sacramento, California, USA
Bikes: Specialized Tarmac, Canyon Exceed, Specialized Transition, Ellsworth Roots, Ridley Excalibur
To simplify, you'd want to have chains with an equal number of links. And to do that, you'd have to have an equal number of teeth. So for every tooth added to the bigger cog, you'd have to subtract a tooth from that side's chainwheel. For example if the drive side is 44x15, the left side would have to be 40x19.