Just bought this bike used. Is the chain too short or is it a problem with the rear derailleur?
Thank you in advance
by norwegian_wood95
Just bought this bike used. Is the chain too short or is it a problem with the rear derailleur?
Thank you in advance
by norwegian_wood95
17 Comments
Chain too short probably, but check if it’s routed correctlly.
Chain is probably too long. Rule of thumb is wrap around biggest front and rear cogs (not through the derailleur), and add ~4 links.
Chain is too long, not too short.
Chain too long, and since it’s probably doing this for a while check the chain wear with a tool like parktool CC-4.2 to make sure you don’t need a new one or a whole new drivetrain
Take 1 link out, or possibly 2. Shift to the smallest ring in the front and the smallest cog in the back. Pull the chain tight to mimic taking out 1 and then 2 links. Find where the chain does not touch itself (that it, where the derailleur cage extends downward far enough).
Chain is too long. Chain is also almost certainly worn out. Check it with a chain wear tool or measure a known number of links with a ruler. If it has stretched by 0.5% or more then replace it. If it is a lot past 0.5% stretched then you may need to replace cassette and chainrings too as it will have been worn out for a while and affected those components. If you’re going to get a shop to replace the chain, show them your picture so they know to re-calculate the chain length rather than replace with another the same length.
As others said, too short. Chain length sizing here
[https://docs.sram.com/en-US/publications/6sfLCOGTn6FE98W8vXLqm0#hashItem=road-12-11-10-speed](https://docs.sram.com/en-US/publications/6sfLCOGTn6FE98W8vXLqm0#hashItem=road-12-11-10-speed)
Is that chain flat on the top?
Chain is at least one pair of links too long. Possibly, the previous owner installed a cassette that’s too big for the wrap capacity of the derailleur and sized the chain to use the big -big combination. If that could be the case, leave the chain as is. Just don’t use the little- little combination.
The chain is too long if the B screw is spot on for where it’s supposed to be
The answer to 90% of these posts
More b tension.
The chain might be a link long but add b tension first. And check length in biggest rings.
It should be mandatory for these kinds of posts to show a “little little” photo and a “big big” photo.
For real? Sram Force AXS and you don’t know enough about bikes to know what the issue is here?
https://preview.redd.it/kw8ej1jgstwe1.jpeg?width=728&format=pjpg&auto=webp&s=5e3fbe311d9c6ae861370aa6d0da81cdca5130a3
I had the same issue with a new Apex AXS setup for my bike. I installed it to the specified chain length, but still had to take out an extra link to make it work fine.
Chain is too long.
Chain polarity’s inside out. Gonna have to flip it manually or else ride backwards till it drifts on its own.
Don’t just cut your chain because everyone here is telling you to do so. If you are in the small chainring in the front normally a sram axs groupset will not let you shift into the smallest cog of the cassette. but if you disconnect one of the batteries you can make it happen somehow and then the chain can rub but isn’t necessarily to long it’s just in a gearing position it can normally never be in. [this](https://docs.sram.com/en-US/publications/2bJvdvYz3DCAfCZVNeUucG/UM%20-%20eTap%20AXS?models=rd-riv1-e-d1#hashItem=chain-installation) is the right way to size your chain for a 2x axs system.