Originally Posted by
Sy Reene
Confused here.. you're saying you've had to replace half of your groupset, but you don't any indications it won't keep working for another 20k miles? IOW parts do wear out
You're aware that chains and cassettes are consumables, like cables and bar tape. They have to be replaced on every bike with every groupset. (Some of the chains were DuraAce, fwiw. I just bought what was cheapest at the time.) They are also not half of a groupset anyway, certainly not in terms of cost.
The 105 shifters and derailleurs and crankset are all fine. I did switch the Tektro brakes for Ultegra, and they're fine too. None show any problems from wear.