>>2002835Depends on how much bigger your cassette will be. Usually chains are sized so when in the bigest chainring and biggest gear, the derailleur is stretched out like picrel. If you fit a bigger cassette, you’ll probably find that the chain is now too short, which can reduce it’s life. In that case, you’d need to buy a new chain and chain tool to cut it to the right size and join it.
Look at the park tool chain length video.
