A wide range drivetrain refers to a big cassette with gear ranges
that is capable to get you up on steep hills and down on the road
The 9 speed cassette features cogs from 11 teeth to 50 teeth
Divide the number of teeth on the largest cog by the smallest
Then multiply that by 100
That gives this 11/50T cassette a gear range of 454%
This is going to make a much wider gear range compared with the old 11-28T cassette
The SRAM SX-4 measures 95 mm and it has been proven to give good clearance
in fitting a 11-46T cassette
The hub is a 10 speed hub
Therefore, no spacer is required to fit the 9 speed cassette
A hanger extension is required to fit the wide range cassette
Tighten the B-tension screw to extend the gap between the guide pulley and the bottom of the cog
Adjust the limit screws if necessary
Let's take a look at the gear ratios with the front 30T chainring and 11-50T cassette
The 1x chainring works beautifully with the wide range cassette on mountain trails and uphills