Is it possible to remove 2 gears in 11 speed cassette and fit to a 9 speed hub? or remove 1 gear in the case of 10 speed. my hub is Shimano WH-RS10 9 speed hub. My current cassette is sunrace 9 speed 11-28. I want to change it to a wider gear ratio and i am planning on using a 11 or 10 speed MTB (11-40) cassette then remove extra gears to fit on my 9 speed hub. My RD is sora GS,and i will also use roadlink to reach 11-40 set up. Thank you!
This will not work. The sprocket spacing decreases by about 0.5mm as the number of sprockets increases. The difference sounds small but you would get awful shifting and indexing problems at the largest and smallest gears.
BTW: 8, 9 an 10 speed cassettes all fit on the same width freehub body. 11 speed road gets slightly wider.
You'll have to look for a 9 speed cassette with the large sprockets you want. Beware you will get big jumps between gear ratios which could negate the benefit of the low gear ratios. Opinions expressed on this site about how well Roadlink or other hanger extenders work are varied, so don't expect the setup to work well straight away.
No you can’t.
The spacers between 9 speed, 10 speed and 11 speed are different. Sprocket thickness between 9 speed and 10/11 speed is also different.
Maybe you could get it working with some special spacers to achieve the same center-to-center distance between sprockets.
The largest 9 speed cassettes seem to be 12–36t.
In any case, 11–40t with 9 speeds would have huge gear steps (~20%).