Originally Posted by
mrmb
Thinking about giving it a try since I have the parts to do it laying around.
My commute is pretty darn flat. A couple small hills that I am ok with walking on.
This would be on a surly steamroller, fixed.
Is never tried anything more than 38 X 13, so not sure what this will be like.
I am no expert, but that is a huge change. You are going from 76.8 gear inches to 97 gear inches. Taking off from a light or a stop could be challenging for you. I am currently running a 49:15 ratio which is 86 gear inches. Personally, I think you should try it and see for yourself. I wouldn't go that high for a commute, flat or not.
I should state my source as well:
BikeCalc.com - Bicycle Gear Inches Chart