Originally Posted by
dr_lha
What? I've repaired my 8-speed on the road without a connector link using a multi-tool based chain tool a few times, so I don't understand this statement. Did I do something wrong?
Probably, and it may cause you to need to do a roadside repair again in the future. Hyperglide shifting, by any other name, makes it possible to shift under load. This puts side stress on side plates forcing them outward on the pins. At the same time, in an effort to make chains narrower, the pins no longer protrude beyond the ends of the plates, leaving no margin for spreading.
So all chains produced since the Hyperglide era (8s and newer) have the ends of the pins peened over the plates like rivets. When you push these through , you break off the overhang, leaving a plain end which won't resist side forces. Shift badly and the plate will move out and hang half on/half off. It may not break right then because there's still some strength, but load it enough when climbing hill, and the plate will let go, and the chain snap.
Whether your chain breaks sooner or later, or never depends mostly on how you shift combined with luck, since it only matters if the shift force is applied to that one joint. So it's about a one in a hundred chance for each bad shift, but keep it up and your luck will run out.
BTW- most people never break chains, but it can happen to anybody. However if you break more than one chain in a lifetime it's probably not just bad luck.