In order to shorten the link without a chain tool, you need an alternative tool like a hammer, pliers or thin nail. They will assist you in pushing the pin easily. You can position the chain over a socket, and hit it with a hammer. Then, you can now pass the bolt all throughout the open holes.
Do all bike chains have a master link? Nope, not all chains have master links. If your bicycle has derailleurs, it means it’s unlikely that your bike’s chain will have a master link.
A master link or quick-release link is a roller chain accessory that allows convenient connection and disconnection of a chain without the need for a chain tool. It acts as a set of the chain’s outer plates, so joining two sets of the chain’s inner plate ends. Such master links may or may not be re-usable.
Place your pliers in the middle of the chain link you want to alter. Slowly open the pliers while they are in the center of the chain link. Start to wedge the pliers higher and higher up the chain-link section until it opens. Make sure you do not twist the chain or the pliers.
Are chain Quick Links reusable?
The quick link is designed for use with 11-speed chains and is, according to Shimano, not reusable. Quick links are dead easy to install. Place the quick link into the chain gap, align and snap together – usually done by applying pressure through the cranks.