Review: KS Lev Circuit Wireless Dropper Post
KS is the latest company to enter the wireless dropper fray with their $699 Lev Circuit. It's available with up to 200mm of drop, which is 30mm more travel than the longest Reverb AXS. Now, this isn't the first time we've seen a wireless dropper from KS – a prototype was on display at Eurobike all the way back in 2016, but it wasn't until late last year that that a production version hit the market.
There are 31.6 and 30.9mm versions of the Circuit, with travel set at 125, 150, 175, or 200mm. I've been testing the 31.6mm, 200mm version for the last three months, enough time to subject it to plenty of rain, mud, and generally messy conditions.
There are 31.6 and 30.9mm versions of the Circuit, with travel set at 125, 150, 175, or 200mm. I've been testing the 31.6mm, 200mm version for the last three months, enough time to subject it to plenty of rain, mud, and generally messy conditions.
Lev Circuit Dropper Details
• Travel amounts: 125, 150, 175, 200mm (tested)
• 30.9 or 31.6mm diameters
• Adjustable air pressure to alter return speed
• IP67 water resistance rating
• MSRP: $699 USD
• Weight: 739 grams / remote: 45 grams
• More info: kssuspension.com
• Travel amounts: 125, 150, 175, 200mm (tested)
• 30.9 or 31.6mm diameters
• Adjustable air pressure to alter return speed
• IP67 water resistance rating
• MSRP: $699 USD
• Weight: 739 grams / remote: 45 grams
• More info: kssuspension.com
DETAILS
The internals of the Lev Circuit are almost identical to the non-electronic version, it's just that the orientation is flipped – the air valve that can be used to adjust the return speed is located at the bottom of the post, and a small motor at the top opens a valve to actuate the post when the remote is pushed.
The Lev Circuit is powered by a 450mAh rechargeable battery that slides in just behind the seat clamp. On their website, KS touts the benefits of a rechargeable battery over a disposable one, saying that it allows riders to “contribute to a greener approach and help reduce their carbon footprint.” You know what's even greener than a rechargeable battery? Not using batteries at all...
The main battery is said to provide up to 8 weeks of run time under normal use, and it can be recharged with the included charger in 4.5-hours. The wireless dropper remote uses a CR2032 battery, and has an LED indicator that changes from green to red when the battery needs to be replaced, typically after 8 months of use.
A single bolt clamps the seat rails in place, and then the angle is adjusted via a 3mm Allen key at the front of the post.
The battery slides into the back of the post's head and is locked into position with the latch at the bottom.
INSTALLATION
Getting the Circuit up and running is dead simple – insert the post and clamp it down, install the remote, and then pair the system by pushing the button on the top of the post and the smaller recessed button on the remote. Honestly, the only slightly challenging part was figuring out that a cap hides the saddle angle adjustment screw – I was used to the configuration of a Reverb AXS, so it took me a couple of extra minutes to get things sorted out.
Installation is when all the measurements start to matter, and this is one area where the longer overall height of the Circuit could become an issue. Similar to the the TranzX post I reviewed in September, the Circuit's length below the collar is fairly short at 291mm for a 200mm post, but the motorized mechanism adds around 15mm to the overall height.
That means if you had a Circuit and, say, a OneUp dropper, the Circuit would need to be inserted 15mm further into the frame than the OneUp in order to achieve the same saddle height. For riders on bikes with short seat tubes and plenty of insertion room that won't be an issue, but it's something to keep in mind if you're trying to fit a post with the maximum amount of drop.
The return speed can be adjusted via the valve at the base of the post.
PERFORMANCE
The Circuits remote lever is large and easy to reach, and the response time is very quick. The amount of force required on the saddle is fairly light, and the post slides smoothly out of the way without much effort. It'd put it on par with the RockShox AXS Reberb post as far as how much (or little) effort it takes to get the seat out of the way, and ahead of the TranzX EDP01 – the post didn't operate as smoothly as the Circuit.
When it's time to raise the seat for a climb, holding down the the remote returns it to full extension. This is where the AXS Reverb has the edge – that post extends much more quickly than the Circuit. I inflated the Circuit to 180 psi, the max recommended, and even then I'd call the return speed adequate but not amazing. On rides with more rolling terrain where the seat is constantly being adjusted the difference between the Circuit and the AXS Reverb is noticeable. The same goes when comparing it to a Fox Transfer – the Circuit is a little less eager to fully extend. Of course, not every one wants a super-speedy post, and I wouldn't call the Circuit slow, it's just not the fastest out there.
I didn't have the time (or patience) to test out KS' claim that the Lev circuit will get 12,000 actuations out of a single charge, but I can say that the run time is more than adequate. I never had the post die out on a ride, and I'd usually charge it every 2-3 weeks depending on how much I'd been riding, or whenever the thought crossed my mind.
One final note on performance is that if you have the post compressed and go to lift up a bike by the saddle it'll extend slightly, a trait that I've only experienced on KS posts. I know, you're technically not supposed to pull on a seat with the dropper lowered, but it happens, and WTB even has a saddle with a built-in handle. It's a fairly minor detail, but one that's worth a mention since I haven't experienced it on any other posts in recent memory.
It's not pretty, but it works surprisingly well. This is the fix I came up with after accidentally breaking the remote lever.
DURABILITY / SERVICE
Part way through testing I accidentally broke the thumb paddle off the remote. I'd laid my bike on the ground and was stepping away from it when my shoe snagged on the plastic lever and ripped it off. That's 100% user error, but it did illustrate that the lever can break fairly easily. The quick fix I came up with involved putting a ferrule over the actuator button, and covering it with mastic tape. It's not pretty, but it actually works very well, and I'm not really sure why KS went through the effort of creating a thumb lever – a simpler push button design would have been easier to execute, and would probably be more crash resistant too.
Opening up the post to give it a refresh is as easy as removing the nut at the bottom of the post and unthreading the collar to slide the stanchion out of the lower. There was still plenty of grease when I pulled the post apart after 3 months, but it was clear some mud and grit had made it way past the wiper seal. A quick cleaning and a fresh coating of grease took less than five minutes, and the entire procedure is a sub-15-minute affair even when working at a leisurely pace.
PRICE / WEIGHT
At $699 the Circuit sits between the $861 Reverb AXS and the $499 TranzX EDP 01. Of course, there's no 200mm Reverb AXS, so riders looking for that length will be choosing between the TranzX and the KS. The KS does lower more easily than the EDP01, and the battery lasts longer, but $200 is a pretty substantial price difference.
When it comes to weight, the 739 gram Circuit is just 28 grams lighter than the TranzX, so I'd call it a draw. Even without the weight of cable and housing, adding a battery and a motor to a post creates a heavier product - a 210mm OneUp post weighs 592 grams, and even after adding in 60 grams for cable and housing you're still looking at an 87 gram weight difference.
Pros
+ Smooth & light action when dropping seat
+ Long battery life
+ Easy installation
Cons
- Middle of the road return speed
- Remote is a little flimsy
- Expensive
Pinkbike's Take
 | For me, wireless dropper posts still fall into the 'neat, but not necessary' category. There's no shortage of cable-actuated options that are reliable, affordable, and don't require remembering to charge a battery, and that's the direction I'd point most riders. That said, for those who want a post that's easy to install (or swap from bike to bike), and creates a clutter-free cockpit, the Lev Circuit is worth a look. I wouldn't mind a slightly faster return speed and a more robust remote, but the long battery life and the fact that there's a version with 200mm of drop does make it a good option. |
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There is a reason why most brands put out Wireless droppers at around 600 - 800 usd... there is a warranty which raises costs.
For example i had a mild issue with my AXS dropper, they sent me a new one with no questions asked. I even had the chance to keep the one with the mild issue which was easily resolved and keeps working perfectly.
Its a complete package. I believe that axs barely needs any service whatsoever which makes its worthwhile UNLESS you forget to charge your bat or not carry another E.g on the derailler or backpack
Add single bolt posts to the Kill List.
Havent used them too much tho..
All this said, people also run wireless Reverbs which are more expensive and people call for the longer travel so yeah, there is demand.
This is only valid if the wireless dropper is cheaper than equiping all your bikes with cheaper wired droppers, which most of them aren't unless you own more than 4 or 5 bikes.
You'll have to pry my AXS derailleur out of my cold dead hands, but Reverb AXS I sold after a couple underwhelming months of use.
What other products are the standard against which others are measured against?
Chris King bearings
Burgtec cockpit
Fidlock
EdBull Media house
Finale gelato’s
So, now I'm choosing from:
1) buy wireless dropper
2) buy bb tool and torque wrench (40nm) and do the thing (already have magnet tool)
3) bring my bike to bike shop (most boring option)
A bottom bracket tool will pay for itself the first time you need to replace the bearings. I got one that attaches to a 3/8 wrench for like $10.
But if your mechanical abilities are really low taking it to a shop would be the wise thing to do.
You can remove that temporary cable and do your build.
?!?!?!?!?!
I have the TransX and it works fine, but I had to adapt to it. I definitely prefer speed and clunk of other posts.
That thing could drop you to the ground faster than you could say "dropper post" when it clipped you in the no-no zone.
I like the fast return, press the lever, bam and it’s up.
Bullshit it's the only brand you've experienced it on. All Reverbs have this issue, and a few others as well. And you've definitely tested bikes with a Reverb. Don't throw KS under the bus all by itself, that's quite disingenuous.
OneUp posts seem pretty immune to it, and the Fox Transfer was explicitly designed to be able to handle it with the use of a spool valve instead of a poppet valve.
So the battery needs to be replaced every year or two?! Ooof.