Bicycles/Maintenance and Repair/Chains/Removing a Bicycle Chain

Figure 3: A SRAM Corporation Powerlink. This type of master link replaces two outer plates of the chain. The manufacturer supplies the item separately and with each of its new chains.

Figure 3: Another type of master link. This type of master link is supplied by CLARKS and has a slightly curved profile. It is cheaper than the SRAM product, though comparative quality data is elusive.

A chain tool, used to reduce its length or to break the chain loop when there is no master link.

If the master link is too tight to remove by hand, these pliers, made specially to grip the rounded rollers, will easily remove it.

Introduction

Removing or shortening of a bike chain usually requires a chain tool which can be purchased for a small amount. Cutting a chain without a master link is said by some to weaken the it. It is preferable not to cut a chain if possible. For example, if there is choice, for example when installing a derailleur, it's better to disassemble and reassemble the derailleur's jockey wheels than to cut the chain. Many older bikes, without a derailleur, have a master link that can be opened with a flat-head screwdriver. Modern SRAM chains have a different design of master link (see image) that is supplied as a part of their chains at the point of purchase.

With a Master Link

The SRAM master link and links that resemble it can be opened by pushing the outer plates of the master link together and inward at the same time. This can be done with your hands, or if it's too tight it may require a special tool (see image). Ordinary pliers have been known to work for some, but the process can be painful and uncertain without the proper item. In an emergency, and provided that you do not mind destroying the master link in the process, a chain tool can be used to drive out its pins. These links are compatible with Shimano chains, as long as they are for the same number of gears on the cassette. i.e. 7, 8 or 9 cogs.

Without a Master Link

If you do not use a master link, it is possible to break a chain with a chain tool (see image). Unfortunately, chain tools are no use at re-inserting pins, so the important thing here is to avoid removing them all the way; they must stay in the outer plates, even when the rollers are free. Place the chain in the tool and carefully line up the tool's pin with a rivet of the chain and tighten until the pin pushes the chain pin far enough out that it's only inserted through one outer plate of the chain. If the rivet is pushed all the way out, it is very difficult to reinsert it. It may take about 6 full turns of the chain tool for an "8-speed" chain, but be very careful not to go too far. In order to check whether you have turned enough, you have to screw the chain tool back and take it off, and see whether the chain can be pulled apart.

Shimano Riveted Chains

Shimano chains use special tapered rivets that can be guided into the holes in the outer plates. These use a pin driver (chain tool) to both drive out the pins and to push the pins into place. On these Shimano chains you should push the original rivet out entirely and replace it with a special replacement rivet as reinstalling the original pin is likely to cause the chain to break at that point.To put back together, reverse the process. If the newly joined link is tight, use the second position of the chain tool to loosen the link. Be sure the rivet is centered on the chain.

See Also

• Master Links  : The Wikipedia article on master links