KS LEV Circuit Wireless Dropper Post

If you asked my 1996 self if one day I'd be riding a 170mm travel mountain bike with a 200mm wireless dropper seatpost that works in all conditions, the reaction would have been priceless. Past me would not have seen an obvious need to drop my saddle to the heights we require them to now, let alone through the magic of sending commands through the air!

KS's seatpost catalogue is vast: there are 14 different droppers for every application under the sun. You can even get an under the saddle lever-actuated one called the ETen. The LEV Circuit is their latest offering with a few tricks up its sleeve and some shortcomings, too. In the past, my local bike shop's discarded dropper post bin was filled with KS Levs and Integras. The lack of serviceability and parts really inched the OneUp, PNW, SDG Tellis and some Reverbs forward compared to the OEM KS post that came with many bikes.

The KS Lev Circuit's engineers managed to fit the actuator inside the saddle clamp. The hollow construction hides the upside down LEV mechanism and the new saddle angle adjustment mechanism, which we will get to later. This doesn't make for a short stack at the saddle side but the bottom of the post is clear from all clutter, save for a Schrader valve to adjust the return speed.

The idea of a 200mm wireless dropper post was intriguing on the Orbea Rallon. The big bike in the stable could use some more clearance for the way down. The 180mm OneUp V2 was well seasoned and was getting crunchier by the day, even after multiple rebuilds.

Since day one, we've been asking for RockShox to make a longer AXS dropper. They still haven't. While I am sure something undeniably cool and catchy is on the way and we'll love the marketing behind it, the KS Lev Circuit has us covered with 125, 150, 175 and 200mm options in 30.9 and 31.6 diameters. My tester is a 31.6/200mm that comes in around 740 grams for the post, plus 45 grams for the remote. The 22.2 mm clamp sits between my Shimano XT lever and the grip. The remote design is simple. The ergonomics work really well on the trail. While the construction of the plastic doesn't scream durability, a couple of crashes have not harmed the remote and it has worked through multiple washes and wet rides just fine.

The post is meant to come already paired to the remote from the factory. My sample did not come paired from the factory but the pairing method was pain free and successful.:

1. Pressing the button on the dropper post in the LED blinks
2. Pressing the recessed button on the remote with paperclips until the LED blinks
3. Wait until the LEDs stop blinking indicating a successful pairing.
4. Repeat if it doesn't work
5. Scream and toss it out the window if it refuses to work

The biggest downside to droppers with batteries is the obvious: running out of juice or not having juice to begin with. The weakest link in the system needs to be well engineered and taken care of. Battery placement on wireless droppers like the AXS Reverb and the KS Circuit makes them prone to catching on the rear tire on a bottom-out and being ripped right off their housing. While it is rare, it is possible. The KS Lev Circuit comes with a healthy 450mAh battery - that's 50% bigger than AXS. The efficiencies of the systems are unknown to me but the 450mAh battery only died on me once at the end of a ride. I had not charged it for weeks, so that's on me! I now charge the battery for an hour every few weeks and remove it during long drives. Remember, motion wakes these wireless systems up, so make sure you remove the batteries and put the dummy units in for drives longer than a couple of hours. Great... new habits!

As an AXS X01 derailleur user, I am used to charging a battery and bringing a spare along on certain rides just in case. Adding a new type of battery to the circulation is a slight concern but I haven't been left dead in the water yet. If I was going on a big journey in the middle of nowhere, while I would trust the integrity of the KS Post, I would also grab a second battery.

The KS Lev Circuit works well when actuated. The return spring is pumped up to 180 psi but it is not in a hurry to get to full extension. While the speed may not be there, the top out sound is nice and audible while on the trail. There is absolutely no play in the post when fully extended or lowered. The action is also the smoothest of any post I have ever encountered. Delightful to raise and lower.

However, there are some issues I found with the post.

My biggest complaint is the way the saddle angle is adjusted. A single bolt system might be necessary due to the design constraints, but most single bolt setups tend to slip under heavy loads. There is a 3mm bolt hiding under a 4mm cap on the front of the head. The 3mm bolt that connects to a nut that corresponds with the saddle clamp has tolerance issues and creates vertical play in your saddle angle. There is no easy way of tightening this play out of the system.

I managed to set my saddle angle, then get the 3mm bolt as tight as possible by rocking the seat back and forth and retightening it and then tightening the 4mm cap to secure everything in position. The play is still there and is noticeable on steeper climbs when I rock back and forth. I thought this might be a deal breaker earlier on but I have grown more used to it and the other benefits of the post make me less frustrated. I think the design can be greatly improved. Both the SDG Tellis V2 and RockShox AXS Reverb have way better ways to secure saddles in place.

Multiple months of repeated abuse and the summer that refuses to arrive in the North Wet put the post through its paces for sure. The system is solid and works exceptionally well. The ergonomics of the remote work for me and the post operates without fuss no matter the conditions. The 2032 coin cell battery in the remote should last 8 months+ under normal use.

700 USD / 960 CAD is a lot of money for a dropper. Cheaper than AXS while slightly less refined in construction, the KS Lev Circuit still offers way longer drop in a tidy and functional package.

KS Lev Circuit