The dropper post length is dependent on a couple of factors; the first being your saddle height and the second being the maximum seatpost insertion depth which you’ll find listed below. Using the values below and the charts supplied by the dropper post-manufacturer you will be able to figure out which dropper post length is best for you.
Slayer 29 carbon: Size M = 230mm Size L = 260mm Size XL = 295mm | Slayer 29 alloy: Size M = 250mm Size L = 250mm Size XL = 270mm |
Slayer 27.5 carbon: Size S = 228mm Size M = 240.5mm Size L = 275mm Size XL = 295mm | Slayer 27.5 alloy: Size S = 230mm Size M = 250mm Size L = 275mm Size XL = 275mm |