I've just bought a replacement 105 R7000 RD for my bike, as the shifting was getting pretty bad.
The price between just buying new jockeys wheels and a complete RD was about £10, after discounts/vouchers etc.
I understand that jockey wheels and cables wear out (effecting shifting), but does a RD?
Is a RD more of a: "it either works or it doesn't" piece of equipment, or do they wear out, causing shifting problems?
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