So, I have my 25 year old mtn bike that I ride in the winter. It only has 10,000 miles or so, so I haven't needed to replace the chain. I take care of it, so that any time the links seize up from rust, I carefully bang them loose with a hammer, or work them with pliers. Then I dribble oil on the chain and it's good for a while.

Anyway, I was riding the other day, looked down at the chain and noticed a few links looked a bit different. Upon closer inspection, I saw that a few links were missing the rollers. I can't see a way to install new rollers, so I guess I can just install a few replacement links as needed ? Right ?