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I tried to change the crank set on a bike brought over to the USA from Europe, assuming all bike chains were the same. The original chainring had 40 teeth and I wanted to try one with 44 teeth. The new chainring had a larger diameter as I expected, but I thought the separation of the teeth at the circumference would be the same. Well, I was wrong. The chain links simply didn't fit the spacing of the teeth on the chainring - after a half dozen teeth the chain was not sitting on teeth at all. Is there a difference between chains in the US and Europe?

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    Never heard of anything. But keep in mind that chains are different WIDTHS, and if you put a narrow chain on a wide sprocket the chain will not seat all the way down into the teeth. – Daniel R Hicks Aug 10 '17 at 22:26
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    Wow. Would love a photo of this. – RoboKaren Aug 11 '17 at 0:26
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    is the bike particularly old, like pre-1920 ? A photo of the chainrings and chain might show something useful. – Criggie Aug 11 '17 at 0:26
  • How old is the chain? Do you know how to tell is the chain really worn, Is the original chainring worn? – mikes Aug 11 '17 at 0:39
  • How old is old chain/chainring. Chains 'stretch' from wear, and the chain ring wears to match. Its likely the chain is old and also need replacing. (search this site for chain wear and how to measure it). – mattnz Aug 11 '17 at 1:50
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There have been exceptions, like Dura Ace 10mm Track, but for the most part 1/2" chain pitch is totally universal. Pairing a heavily worn chain or chainring/cog with a new part can result in what you're seeing, though, because of the mismatch in pitch that develops as chains wear.

  • It's a brand new Jorvik electric tricycle. We had it shipped to the US from England, and the saddle was pressed against the chainring in the box and bent it a little. So both chain and chainring are new. There is one gear ring at the front - the chainring - and a 6-speed derailleur at the back. The Jorvik chainring is a 40-tooth ring, and I tried this 44-tooth crank set. amazon.com/gp/product/B00FNT194E/… – John Larysz Aug 12 '17 at 17:20
  • Jorvik are sending me a new chainring but I'm in a hurry. I couldn't make the 44-tooth chainring work so I beat the bent ring until it was flat enough to function. The bike is now riding well, but I'd still like to know why the 44-tooth crankset didn't fit. – John Larysz Aug 12 '17 at 17:22
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tl;dr: no, all chains in common use are the same pitch (the links are 1/2" long). However, there are two widths in common use, and you have the wrong one.


It looks like the Jorvik has derailleur gears, is that right?

If so, it probably takes a 3/32" width chain, but your crankset is the BMX/track standard 1/8".

Because the teeth have a taper, your chain fits some of the way on and then sticks. Because it's sitting too high, the effective pitch of each tooth is greater, so it looks like the chain and ring have different pitches. Actually, the pitch is the same 1/2" in both cases.

If you do have derailleur gears, you can't just get a 1/8" chain to match your crankset, because it won't have the lateral flexibility needed for a 3/32" chain to change cogs. Getting a 3/32" crankset (or a 3/32" chainring for your existing crankset) is the right choice.

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