What Is the Difference Between 3/32″ and 1/8″ Chains and Sprockets?

One of the most common stumbling blocks for people coming into single speed cycling is the difference between 3/32″ and 1/8″sprockets and chains? A 1/8″ chain is the most common chain found on single speeds, and 3/32″ chain is the most common chain found on derailleur equipped bikes. A 1/8″ chain will fit on parts that are either width. 3/32″ chains will only fit on parts designed to work with 3/32″ chains.

Do you want to know more?

There are a million forum posts where people argue back and forth about 3/32″ and 1/8″ chains and which is stronger, and which will last longer. One of the things that I think confuses people is the use of fractions. A 1/8″ chain is 3.18 mm, and a 3/32″ chain is 2.30 mm. The argument usually ends in favour of the wider 1/8″ chain, but in the real world, you’ll not notice a vast difference provided all your parts are fitted and maintained correctly.

One of the reasons you might want to use a 3/32″ chain is to help with chainline issues. The 3/32″ chain will be slightly more flexible than a 1/8″ chain, which means it will be a bit happier if your chainline is not very straight. Using a track frame and track style crankset you should not have this problem. You will be more likely to have chainline issues with a geared frame conversion.

If you think maintenance may be an issue, I mean who really wants to spend hours cleaning their bike, and you will be riding in pretty muddy conditions then a 1/8″ chain might just last a little longer. If conditions are terrible, then you can expect whatever chain you use to create a grinding paste that will wear down your drivetrain.

At the end of the day though, 3/32″ chains were designed for shifting gears. You won’t have gears on your tracklocross, so perhaps then that makes your mind up.

I’ve also not gone down the road of 3/32″ chains being lighter, as really, who cares?