My chain BROKE!

Yesterday we drove 40 minutes to meet some friends for a 30-mile ride that detoured into an apple fritter festival. We've never gone riding with these friends (they're bike commuters and runners, not really long-distance cyclists, but they're real-life friends), so we were super excited to be finally getting out with them.

Four miles into the ride, I shift as I'm starting a light ascent and my chain BROKE! I coasted to a driveway and looked down to see a single length of chain. I've never even heard of this happening before! Is this a thing? I'm guessing I may have dropped my chain which put pressure on the removable link (the weak link, if you will...) and popped it off, but it happened too quick for me to really know. As soon as I heard the tell-tale noise of what I assumed was a dropped chain I stopped pedaling, so I don't think it dropped and then broke, it appeared to be simultaneous.

Luckily, the story has a happy ending. While the boys biked back to get the cars, my friend found the removable link that popped off, and I figured out how to get it back on. The link had keyhole-shaped holes on either side so it was just a matter of slipping it in correctly and pulling the chain tight. Another cyclist stopped when he saw us in trouble and helped out. When the boys came back with the cars I was riding up and down the driveway problem-free, so we ended up leaving the cars nearby and finishing up the ride, with a bonus 4 miles as we repeated the beginning of the ride to get to the cars. Everyone got their apple fritters!

I'm going to take the bike in to a shop just to have someone check it out -- good idea, right? I'm just wondering if I'm missing a tiny piece of hardware that is supposed to prevent that from happening.

No, it happens, just not very often. I've had it happen with very worn chains, or with chains that get stuck somewhere really stupid :rolleyes:.

From installing chains with master links I think it's quite probable for the link to be a weak point if installed a little sloppily, and I can see how one can bend or break. You were lucky the link was entire and could be re-used.

I don't know how much wrenching you like to do, but Park Tool has a brilliant little tool to check chainwear with. It's cheap, and easy to use. It will tell you if the chain is worn and needs changing. Changing a chain is easy, and fun :)

Master links are not a weak point, but if not properly installed they can disengage.

Technically speaking a master link is actually stronger than the pin-joined side plates of the rest of the chain.

this happened to my husband about 2 weeks ago right after he took his chain off to clean it.
How did it happen? He didn't fasten it tightly enough when he put it back together.
But chains DO break.