# 1/8 versus 3/32 chains and cogs, what is the difference?



## gordy748

Okay, bad question, I know it's the width.

That aside, is there any advantage to either? My thinking is 3/32 is lighter (by a teeny bit) and 1/8 is longer lasting (by quite a lot).

And do you need a matching cog/ chain ring/ chain or is some mixing ok?


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## wim

If the chain ring, the cog or both are 1/8", you need a 1/8" chain. If the chain ring, the cog or both are 3/32", you can use a 3/32" or a 1/8" chain. Because the 1/8" chain is a loose fit on a 3/32" ring or cog, it generally runs a little noisy on 3/32" rings or cogs.

Assuming identical maintenance, I think durability depend on the quality of the chain. There are crappy and good 1/8" chains, just as there are crappy and good 3/32" chains. Not sure why a 1/8" chain should outlast a 3/32" chain by a lot, wear is wear. Keep in mind that chains on single-cog bikes never have to bend laterally, so they are stressed less than chains that get shifted.

/w


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## BianchiJoe

What wim said. ^ I've run 3/32 cogs and rings with an 1/8" chain with no problems and very little noise, but at the moment I have a 3/32 chains on all of my singlespeeds.


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## foto

the difference is 1/32 of an inch...


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## gordy748

Thanks for the info guys. Very much appreciated.


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## Dave Hickey

I have bikes with both....very little difference in wear... I run 1/8 rings on all my bikes...Cogs are a mix 3/32 and 1/8.

Another thing to think about is installing/removing the cog

If you do your own maintenance and already have a 3/32 chain whip, buy a 3/32 cog...

You can't remove an 1/8 cog with a 3/32 whip...


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## dookie

3/32 is generally repurposed geared stuff... 

Ramped chainrings are a bit more subject to throwing the chain.

Chain is more flexible laterally, and thus more tolerant of less than perfect chainline.


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## ldotmurray

Dave Hickey said:


> I have bikes with both....very little difference in wear... I run 1/8 rings on all my bikes...Cogs are a mix 3/32 and 1/8.
> 
> Another thing to think about is installing/removing the cog
> 
> If you do your own maintenance and already have a 3/32 chain whip, buy a 3/32 cog...
> 
> You can't remove an 1/8 cog with a 3/32 whip...


I found this out the hard way. My knuckles were not happy with me.


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