30.9mm will be the seatpost diameter but not the seat tube diameter. If it's an M2 frame you need a 34.9mm front mech - I have a 98 M2 Stumpjumper Comp.As per the title, my 98 Stumpy hardtail needs a front mech. anybody have one thats in decent condition
XT 8 speed Front Mech - 30.9 Bottom Pull
Thanks