Last week, I noticed a stiff link in my KMC 10 speed chain. The chain was installed in December, and probably has 100-150 miles on it so is rather new.
I couldn't get the stiff link to loosen at all with a chain tool, so I removed the stiff link and replaced it with a leftover from when I shortened the chain to fit the bike. I put the chain back together using the same pins, no missing link or Shimano replacement pin.
Is it alright to do this? If not, how long till I die to death?