Originally Posted by Goat Herder
Chain wear, or chain stretch, becomes an issue with extensive cycling. Although the overall effect is often called "stretch", chains generally wear through attrition of the bushings (or half-bushings, in the Sedis design) and not by elongation of the sideplates.
Good reading there,,
As a kid I knew they never stretched,,I always just thought the rollers broke in more after use causing the need for adjustment,,guess i was close..lol