is a Schwinn AirDyne exercise machine. It was in for repair (we used to sell fitness equipment in the winter) today. When you take the cover off, your will see an idler pulley to keep the chain tensioned.
The problem? Spring for tension was broken.
The fix? Shimano rear derailler spring. It was fun to get it out, as one end is a little bit of a pain! Rivet. But it worked like a dream!
Whose idea? Yep, me. It’s nice to know all those years of edumacation paid off somehow!
You may ask, why not use a Schwinn part? We aren’t really a dealer anymore. And the derailler was a used part in very good condition.