I would like to put some of my older 9sp kit on my boy’s 20″ wheel bike. It is currently 7sp with a grip shift. He struggle with getting up the cassette with the grip shift yet can operate my paddle shifter no problem.
I have a SLX GS rear mech and the bottom jockey wheel looks as though it will drag on the ground.
Can I use an older shimano 9sp road mech with a nice short cage? Are the pull ratio’s the same?
Alternatively, can I fit a shorter cage to one of my old 9sp MTB mechs? Has anyone done this? If so, which cage was used?

Thanks in advance.

Yep, Shimano 9 speed MTB and road play together nicely, at the rear at least.

Thanks Midlife.

I am also trying to shed a little weight out of the bike too. I recon a 9sp xt cassette with be half the weight of the wrought iron 7sp that is on their.