[Closed] 10 speed shifter / 9 speed mech / 8 speed cassette

no the spacing on a 8 speed cassette is very wide in comparision to modern standards.

In fact im not sure any of it will work together,

No

No, cable pull on 10 speed shifter is different.
An 8 speed shifter will work with an 9 speed mech though.

OK thanks. What mech and shifter combos will work with 8 speed cassette - does mech and shifter have to be 8 sp too?

What defines the pull ratio - the mech or the shifter?

Shifter defines the pull ratio, mech is designed to work with the pull ratio.
Shimano changed the pull ratio for 10 speed so 8 or 9 speed mech should work with an 8 speed shimano shifter (I used to run 9 speed XT mechs with a XT 8 speed shifter).

What mech and shifter combos will work with 8 speed cassette

The shifter has to be 8 speed. The mech can be 7/8/9 speed.

As above, 8 and 9 speed deraillers are interchangable. The spacing on 8 and 9 speed is different, so you cannot use 9 speed shifters with an 8 speed cassette.

OK thanks a lot everything, he has ordered an 8 speed mech and shifter for simplicity 🙂