The latest version of Easton’s lightweight EC90 Offset seatpost is impressive, with a one-piece, all-carbon design, a user-friendly clamping system and excellent saddle adjustability. The only shortfall is that the 350mm length is a little short for longer-legged riders.
Easton claim to have remedied the perennial problem of damaging a carbon fibre post by over-tightening it in the seat clamp through use of their RAD (Relief Area Design) and TaperWall technology. By flattening the aft side of the post and adding material where needed, the seat clamp’s force is dispersed much more evenly through the carbon tubing, greatly improving durability.
“The post has more material in the area that will be clamped for increased strength; less elsewhere for lower weight,” Easton’s press officer Peter Nicholson told BikeRadar. "This combines with a carbon layup that's designed to allow some flex in the post, smoothing out the ride."
Out on the trail, this built-in flex is tangible – the EC90 offered a slight but noticeable improvement in smoothing out the bumps compared to the older-generation RaceFace Next carbon post it replaced on our main test bike. At the same time, there wasn’t any noticeable flex or wandering, even under a 205lb test rider running the post at full extension.
Setup of the EC90 will make many a mechanic very happy. The lower piece of the all-carbon clamping system slides easily to the side to allow painless saddle installation. Once the seat is installed, fine-tuning both fore/aft and nose angles via two 4mm bolts (hidden inside the upper body but easily accessed) is a breeze.
Over weeks of riding and racing in both mucky, and dry, dusty conditions, the EC90 never so much as hinted a squeak or creak. The clamp held the saddle in position flawlessly, and swapping out saddles or the post itself between different bikes didn’t cause any problems at all, either.
The only issue we had was that the 350mm post was a little too short for one long-legged test rider to run on one particular bike, so riders who often need a 400mm (or longer) post may not be able to use the EC90. Other than that, it's a fantastic post.