Chain touching pulley?

how can this happen? i brought my bike for full servicing. they replaced the chain.
i use this mostly on trainer.
then today i unmount it because i need to ride outdoor using this bike
then i discover the chain touching.
it means my chain has been like this for months!
is this because chain too long?
i will scold the bike shop if they didnt check.

Yes chain is too long. However they might have fitted it that way if you have a larger cassette than is technically possible so at least big big won’t rip the mech off. You’re not usually meant to be in small small so most people wouldn’t notice. What gearing do you have on the bike?



Are you checking this with the bike upside down? If so, its not the right way to check.

There are a number of ways to review chain length. But I like using the small ring, small cog method. When in this combo, the rear derailleur will be similar to your pic.

A related adjustment after setting chain length is using the B tension screw to set the gap to the cogs. Usually done on the larger ones, but should be checked in. This small-small combo to make sure you don’t get contact as shown.


Chain too long.

Check that the chain is long enough for big-big, with some to spare. Removing a pair of links could be your answer.

1 Like

Issue fixed, bike shop remove 2 links. No more touching now. Thanks all.