Originally Posted by
JerrySTL
An 8-speed chain will also work perfectly for 6- and 7-speed bikes. I'm assuming that by 12-speed, your bike has six gears on the rear.
+1 You will see these chains listed as 8-speed or 7/8-speed or even 6/7/8-speed. All will work properly. Remember, that these newer chains must not be joined by reusing a standard pin. If you have to shorten it a bit you must always use the specific joining pin (Shimano) or master link (SRAM, Wipperman or KMC) provided by the manufacturer.