how can you index a 9 speed 11-46 tooth cassette if the gears arent equally apart I am looking at purchasing a 9 speed 11-46 cassette but on inspection the bigger cogs are not equally apart from the smaller ones.  How would you go on with indexing (I use a thumb shifter 9 speed) if the gaps aren't equal as I'm guessing my shifter pulls and pushes the same amount of cable per click.

EG Cassette Range: 11-13-15-18-21-24-28-32-37-46T these arent equally spaced apart in particular the biggest ring is alot further away from 2nd ring 9 tooth difference than the others that are 2-4 tooth difference.
It sounds like you're talking about the tooth difference, and not the horizontal spacing between cogs.  Most cassettes are &quot;uneven&quot; in this sense.  It does not affect indexed shifting, so long as the derailer can accommodate the max number of links difference and can &quot;reach&quot; as high as the largest cog.