REDSHIFT ShockStop Suspension Seatpost for Bicycles

Product Information

I've recently bought one (Suntour SP12-NCX) and I'm super impressed - I ride mainly on the road in Devon, where the surfaces aren't exactly smooth. Best method: Use a pair of calipers to directly measure the diameter or take your bike to the local bike shop and they will be able to measure it for you.

I don’t know if this is the effect of two springs working together or not but the feel changed for the better. There was no bottoming out and the suspension performance was quite noticeable. As we just saw in the test, if you’re riding on rougher terrain with larger forces coming from the rear wheel, you will benefit from more suspension travel as it can dampen more vibrations. I’d say most rough roads can be comfortably cycled with just 35mm of travel, but 50mm+ may be required if you’re hitting bumps at a higher speed (on an eBike, for example). Apart from tire pressure the next thing when it comes to bike comfort and this is proven is seatposts. Responsible for a lot of your bikes overall comfort while riding. When compared to a frame, seatposts flex much more which equals better comfort. So at the end of the day you are probably better off getting a flexible seatpost then a new bike if comfort is the issue. Lastly, we have air springs, which are sometimes used in telescopic seatposts. The main advantage is that you can adjust the spring stiffness to a higher degree of accuracy. Suspension Seatpost DesignsBut I did not stop there. I wanted to find out what would happen with a firmer suspension tune (this time to level 4).

I used an Argon 18 Dark Matter gravel bike for this test. The bike was set up with Challenge GravelGrinder 700C x 42mm tires. The Redshift sestpost has a lot of moving parts so there is always a question of long-term reliability. I’ve only gotten four or five rides in with the new Thudbuster, but I’m quite impressed. The redesigned seat clamp is fantastic, and I found the new elastomer system to work very well. Unlike some of the softer, coil-sprung posts, the new Thudbuster offers a nice mix of chatter dampening and medium-hit suspension to take the edge off of sharper bumps. And, it doesn’t feel as if it has as much of an effect on pedaling efficiency as other, longer travel posts do. At half the weight (~300 grams) and half the travel (20mm) of most squishy posts, it performs closer to the best carbon seatposts available.

Internals

It’s constructed from FACT carbon fibre to a 27.2mm diameter with a cylindrical aluminium head for easy saddle adjustment. And finally, the air seatpost improved things a bit (6% improvement) but clearly requires a higher bump force to activate than other suspension seatposts. I put an extra spring into the post, set the firmness to level 2 (for 90kg riders), and went for another test ride. Big surprise! Regular dropper seatposts have very little vertical flex, which is an unfortunate consequence of their telescoping design.