I am replacing the 12-23 8 speed hyperglide cassette with a 12-27 9 speed hyperglide cassette.
I was able to put the new cassette on the hub without difficulty. I was worried that it wasn't going to fit, but it seemed to go just right.
The next task is to replace the chain. I don't know anything about chains. But it seems to me that the new 9 speed chain should just be 4 lengths longer than the old 8 speed chain.
Is that right?
The bike at issue: