Originally Posted by
dinkjs
I have downtube shifters...so i have no idea about indexed or friction shifters
Indexed shifters means they "Click" into each gear as you shift, so you don't need to finesse the shifting. Early indexing was done with donwtube shifters, until integrated brake/shift levers came out. Before indexing, downtube shifters were "friction" meaning that the shift levers were kept in place by the friction of the bolt, and you had to find the correct gear yourself, sometimes overshifting & having to shift back a bit to get it just right.
With indexing, the shifters, rear derailleur & cassette need to be compatible so that with each "click", everything moves & lines up correctly as you shift from one gear to the next.
With "friction", your hand & ears adjust until it's quiet ..... noisy clattering means it's not quite in gear. You can mix & match a lot of different components because there's no precise indexing involved.
The late 1980s was when indexing started.