Change rear derailleur can that require a different chain length?

[Zudnik]

Was just out in the garage taking off the NX and putting on X01 axs. But now it seems like the chain is WAY too short. I didn't change anything else so an surprised by this or did I just royally bugger it up?

 

[flash]

It can if the cage lengths are different or the cassette or chainring is different. Having said that I have just swapped out a NX/GX Eagle drivetrain to X01 AXS and the chain length was fine. Are you sure you have everything set up correctly like the B screw etc?

Gordon