Originally Posted by
woodrupjoe
My other stupid question is when did rear spacing go from 120mm. to 126mm. to 130mm? I realize that it didn't happen overnight, but ballpark is OK. Just curious about that one.
I'm sure I could think of some other stupid questions, but that's enough for now. Feel free to post your own.
Feel like I dropped the ball somewhere this last couple of decades.
cheers, Joe
Spacing was due to more gears. The actual space between the gears stayed close to the same the freewheel just got wider.
I think 7 speed speed is when it went 126 then with the introduction of 8 speed it went to 130. Mountain bikes went to 135 because as the gear cluster got wider some of the hubs were more narrow to fit the gears. The more narrow the hub the weaker the wheel becomes to side loading. Thats when Shimano started a Mountain bike line of parts different from the road bike line.