I'm currently repurposing an old frame and replacing the drivetrain. If possible I'd keep the old 7 speed drive train the bike had together in case I ever find a use for it. The chain is an HG40 quick-link. There's plenty of info online about joining chains with quick-links but little about breaking and reusing them.
Is there a trick to the quick link to separate the chain so it can be easily reused or do I just need to break it with a chain tool?
The install Tech Doc can be found here.