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.


2018-2020 Thunderbolt carbon:

Size XS = 200mm

Size S = 225mm

Size M = 225mm

Size L = 245mm

Size XL = 245mm


2019-2020 Thunderbolt alloy:

Size XS = 170mm

Size S = 200mm

Size M = 250mm

Size L = 250mm

Size XL = 250mm