CrankBrothers Joplin 4 seatpost review

Clever post improved for 2010

Our rating 
3.5 out of 5 star rating 3.5
GBP £199.99 RRP | USD $250.00
Crank Brothers Joplin 4 seatpost

Our review

Better seals and internals, and increased height drop for less money. It’s looking good so far
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The original Joplin dropper seatposts certainly weren’t without flaws. Sealing issues caused them to seize and excessive play developed very quickly. The new version squares up to these problems and has new internals to fight them off.


There are two keys and keyways to hold the post straight, instead of one, and they’re suitably longer to further increase durability.

In our first month of testing we can report minimal play. This is despite some harsh weather conditions and a couple of decent sized crashes, which previously resulted in instant slop as the guide keys got flattened on impact.

The main wiper seal is a lot tighter than before and does a very good job of keeping dirt and water on the outside, with no ingress into the bushes so far. The post has needed priming a few times, but this isn’t an issue, because doing so is tool-free and takes seconds.


The extra inch of height drop, now at 101.6mm (4in), is much better for steeper trails or more aggressive riding, and a price drop to under £200 brings it in line with the competition. It’s still early days, so we’ll update you as we continue to use and abuse it.

Product Specifications


Name Joplin 4 Lever Seatpost (10)
Brand CrankBrothers

Description 4in adjustment range
Weight (g) 505
Diameters Available 30.9mm 31.6mm