Review: Crank Brothers Kronolog Dropper Post – Weighed, Dismantled & Ridden

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

Crank Brothers’ Kronolog dropper seatpost arrived a few days in advance of the official introduction back in March, so we’ve had a couple months of riding on it. We’ve also dismantled it, weighed it and given it a good once over.

The basics:  It’s a mechanically controlled air spring post that’s infinitely adjustable. A big deal is made of preset positions by Fox and Specialized with their posts, but if you like being able to set it where you want it, the Kronolog obliges with a simple push of the lever. Rather than slotted channels to prevent rotational play, Crank Brothers flattened the sides of the telescoping section and shaped the internal seals and guides accordingly. The result is a (thus far) smooth operating post with as close to zero play as we imagine possible. Other nice features are a secondary air chamber that damps the return speed, slowing it down as it nears top out and keeping your special bits safe. When you pull up on the saddle, it won’t raise the seat because the jam plates lock the post into position in both directions. Lastly, the lever is very easily mounted under or over the bar and on either side.

Fit and finish on the post and remote are top notch, as with most Crank Brothers products we’ve seen. And while the Kronolog solves some of its predecessor’s problems and addresses common complaints with dropper posts in general, there are a few concerns worth mentioning. Drop in for the full review…

UNBOXED & WEIGHED

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

A simple Schrader valve on the bottom is filled with a shock pump. Max pressure is 100psi, but I found 70psi to 80psi to be adequate. Lighter riders may want less, but it’s easy enough to experiment. The key is to get the pressure light enough that you can use your weight to only drop it as far as you want. To0 firm and it’s hard to “fine tune” the position. Too light and it’ll just drop too fast.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

The saddle clamp is 3D forged as part of the telescoping post, not bonded on. This makes it stronger and lighter. It clasps the outside of the saddle rails and squeezes them toward the center piece, which prevents the rails from bending inward. Angle and everything is adjusted via a single T25 Torx bolt on the left side. After a bit of time on the trail, we had to really loosen it up to make small angle adjustments, but it never slipped. It is set at a slight angle already, so you’ll need to make sure it’s put into the bike the right way when first installing it, otherwise you’ll never get your saddle flat.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

The lever is simple, lean and beautiful. Both of these parts are offered in colors to match other CB components.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

Slide the cover off and you’ll see the cable actuated jam plates. When “closed”, they’re literally jammed into the post at opposing angles on both front and rear, giving them four contact points to hold it in place. Because they’re opposed, they prevent upward and downward movement until you press the lever.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

We got the larger 31.6 post. It weighted in at 566g. The cable comes preinstalled and is 40″ (101.5cm). All of our testing so far has been on a size Large Devinci Atlas 29er, and this was exactly the perfect cable length with the entry point on the post facing forward. If the top tube were any longer, we’d probably have had to put a longer cable and housing on it.

On that bike, there was plenty of static post. Even at 6’2″, I had a bit more than two inches of post left before it would have hit the minimum insertion.

PERFORMANCE

Our testing so far has been on a lot of XC-ish trail, which puts the rider’s weight on the post a lot more than constant gravity riding. We’ve taken it to the mountains, too, and used it as intended. On those rides, the action was smooth and quick, and return to start was predictable. The slow down in return speed at the top is greatly appreciated.

On the flatter rides, we were swapping the bike back and forth between riders. Rather than pull out the mini tool each time to adjust saddle height, we simply pushed the lever and played with the post until it felt right. Lazy, yes. But a good test: In reality, dropper posts are generally used fully up or fully down. There aren’t too many instances where you’re going to spend much time in a middle setting. We did spend a lot of time in various positions, though, and the post held solid the entire time.

Based on horror stories we’ve heard of other posts developing play or failing after a few rides, two months on this one without issue tells us it’s off to a good start. We’ve had zero problems with the post and it’s developed no play. That said, there are a few issues we’re watching closely, all of which we discovered as we dismantled the post to flip the cable entry to the rear (and feed our insatiable desire to tinker and see how things work!).

DISMANTLING & SWITCHING CABLE ENTRY TO THE REAR

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

Our testing so far has been with the stock set up, and that’s with the cable entry on the front. In order to flip it around to the rear, you need to disassemble it. This requires a Park Tools SPA-2 spanner tool to unscrew the bottom cap. First, remove the Schrader valve cap, then have at it. Ours was pretty tough to open, so I’d recommend leaving the saddle on and using it as leverage (that’s why I’m standing on it). If you love your saddle, put it on a towel first.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

Once that one’s off, squeeze the lever and slide the post all the way down to get to the second piece you need to use the spanner on (left). This one was much easier to remove. The full internals are on the right (click to enlarge). Once that’s pulled out, press the lever again and pull the telescoping post out, spin it 180º and reinsert. This effectively puts the cable entry point on the back of the post. Honestly, we wish the post’s saddle clamp weren’t directional; this would make it much easier to run the Kronolog in either direction right out of the box.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

The piston has a good bit of grease to keep it sliding freely. On the bottom of the piston is a spacer (about 10mm) that can be moved above the piston to shorten travel by that amount. Add up to 20mm in spacers. Stock travel is 125mm. Shorter riders on smaller frames may need to limit the travel to be able to fit themselves on this post, which is why they made it internally adjustable.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

As I was poking around the seals, I noticed a couple of metal shavings (two of them form an “X” just above a seal in the photo on left). At first, I thought perhaps they were manufacturing remnants. That wouldn’t have been good, but at least it wouldn’t have meant anything was wrong with the post.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

Unfortunately, the source appears to be the telescoping post. It looks as though the metal jam plates dig into the post slightly and are scraping metal off. On the left you can see markings from all the various positions we’ve set the post in. Most of these marks are just normal metal-on-metal superficial scratches and aren’t worrisome. A few, though, are larger and are visibly scratched into the post.

I’m holding off on forming a final opinion yet. Yes, at first glance this looks bad. Real bad. But it could be that just a few bits came off and now things are fine. Time will tell, and I plan on putting a lot of time on this post over the summer. Worst case is that the post and/or jam plates will scratch, scrape and wear off enough material that they’re no longer able to hold the post in place.

crank brothers kronolog adjustable height dropper seatpost review weights and dismantle

The other issue, which is both minor and quite possibly entirely my fault, is that the cable housing cracked right at the entry point. It seems kinda weak that it would crack almost to the point of separation so early in its life, and we haven’t wrecked while aboard the post, but who knows. It’s a minor thing…the post still works as is and changing out the housing isn’t that big of a deal. I may need to do it anyway to extend the length…and I think Gore Ride-On makes an upgrade kit for just such things. Mmmmm….Gore Ride-On.

NOT SO DEEP THOUGHTS

Overall I like the post. I want to keep liking the post. There’s a lot to like. I want Crank Brothers to have a winner on their hands. But at the moment, I’d say hold off on purchasing. I’ll talk to Crank Brothers and see what they say, and we’ll keep riding it and report back.

Comments

Laos - 05/10/12 - 3:47pm

Although I have not tried or even seen the seat post from close by, I thought from the start that is is just bad mechanics. It is obvious that the post will be one day so badly scratched up that it will not work properly at all positions. Especially taking into account the force that each rider exerts on it every single time it moves…hope I am proven wrong

Steve M - 05/10/12 - 3:47pm

Droppers pose rather substantial engineering problems. It seems that another ounce or two of steel in some key areas in most of the posts would greatly benefit the breed. I am surprised that CB would release this post with an aluminum wear surface given the extremely high contact stresses the clamps put on it.

Brian S - 05/10/12 - 4:23pm

I have tarp poles for camping that pretty much use the same style of clamp to keep the pole elongated. The clamp wedges on to the pole and the pressure is concentrated on two opposing small points. Just as you saw in your testing, these areas either get shaved off or they get notched in a way that the clamp starts to get stuck in the notches as you try and adjust the length.

It happens on my tarp poles, and they aren’t being subjected to constant impacts like a seatpost.

This is a failed design on CB’s part.

Oderus - 05/10/12 - 4:28pm

Huh! A Crankbrothers product that doesn’t hold up. That’s odd.

boobie - 05/10/12 - 4:35pm

Seems like your review is consistent with nearly every other review. “I want to like it, but it’s a total failure” – although no one seems willing to say it quite that strongly. There is no way that every single one that I’ve seen a review of should have so much damage after two months. I’ve riddent a Command Post for 2 years – not a single issue. The reverb also has set a very high bar. This doesn’t seem to come close to either of those products. Although, I think the location of the cable attachment is the future of dropper posts.

mountguitars - 05/10/12 - 6:17pm

I’m not surprised this product sucks. Only suckers would buy this.

dave - 05/10/12 - 6:24pm

the metal shavings indicate a design flaw…the detents will wear away and the clamp will start slipping.

this was obvious when this post was released..

Rob - 05/10/12 - 8:34pm

Sounds like pretty much every other Crank Brothers product – looks nice but about a durable as a pencil.

What we need is Cannondale to shrink their Lefty technology into a dropper post.

fanboy - 05/10/12 - 8:34pm

I can’t stop laughing. Another Crank Brothers product that’s failed upon release.

Actually, it’s no longer a laughing matter any more. it’s just plain pathetic.

nh - 05/10/12 - 9:11pm

Pinkbike did a review and had the same problem to the point where their post would slip – http://www.pinkbike.com/news/Crankbrother-Kronolog-Telescoping-Seat-Post-Tested-2012.html

I had hopped this product would live up to the hype but I am sticking with my 3 position Specialized Command post now.

John - 05/10/12 - 9:18pm

This is just what we’ve come to expect from Crank Brothers. How does this company want to be taken seriously when they design such garbage products? The fact that they still use a double spoke design on their wheels (that never even worked in the 90s) shows you they lack a total understanding of engineering principles. Should be named Fail Brothers.

shreddie - 05/11/12 - 12:48am

“Worst case is that the post and/or jam plates will scratch, scrape and wear off enough material that they’re no longer able to hold the post in place.”

I think you meant to say, worst case is the jam plates wear enough material on the front and back of the post that it weakens the telescoping portion to the point of failure – an abrupt snapping of the post.

Won’t find one on any of my bikes.

Dizza - 05/11/12 - 12:57am

Happy to say my bike is now entirely crank bros free. Finally got rid of my Joplin. Threw it in a campfire and it turned into a flame thrower. Coolest thing I’ve ever seen out of a CB product. They make very good looking junk and that is all. Customer service sucks too. Never again.

Sam - 05/11/12 - 1:12am

I’ve seen three long-term reviews of this post now, and they’ve all had the same problem with the clamps marring the post surface. I’m pretty disappointed, because when I first heard about this design I thought it seemed like a sound concept. Too bad Crankbrothers couldn’t nail the execution.

gringo - 05/11/12 - 2:30am

bummer.
our sample post did not even make it on to a test bike, the 1920′s friction / clamp ‘technology’ leaves a bit to be desired.

RS1800 - 05/11/12 - 5:04am

ROb, you’re 200% right!!!

For the rest nothing more than another crankbrother product…

tirider1 - 05/11/12 - 7:28am

Where is there a mention of failure?

BT - 05/11/12 - 9:09am

If Crank Brothers made brakes, would you use them?

Yeti - 05/11/12 - 9:28am

Agree with most comments except the one about CB customer service. I’ve had nothing but good experiences with them. Pedals failures, RA straight away and replacement. Joplin failures, great help getting it sorted. Customer service seems to be their one saving grace, really.

MTB - 05/11/12 - 10:29am

Customer service is the only thing saving them from going under. The only reason I still buy their products, even though I know they have durability issues (huge understatement), but after being disappointed with the Kronolog in a big way (I’m getting slippage after couple of weeks) I think this is it for me.

P.S. Unless you’re doing a lot of downhill/descents, I think adjustable seatposts are major ‘overkill’.

BT - 05/11/12 - 11:04am

CB has great customer service because they have to

MW - 05/11/12 - 3:58pm

Crap-brothers!

LMFAO - 05/11/12 - 9:25pm

Crank Brother product…is it broken yet? How about now? Now?

Happy to say I never bought a single piece of their crap, watched my buddies suffer thru all the crap they’ve put out. 10 years from now they’ll be remembered (past tense) as the ONZA of the 21st century. Remember the crap they put out?

Ron - 05/12/12 - 4:50am

I hope that crank brother read what all guys and test report , stop selling the item and come wirh a new one
The worth thing company can do is to sell a bed product , I am very disopunted but thanks all of you and the reveiew since i thought to buy one but and now for sure i wili Not buy thanks

fanboy - 05/13/12 - 5:34pm

@ Ron

what Crank Brothers will do, is release an “improved” model next season and then offer a “low cost upgrade” to the new post.

Let me see if I understand this, you buy a product, it sucks. So you should pay more money to upgrade to their new one, that is now perfect right? (cue much laughing)

How about just getting the damn thing right the first time?

Or is their business model based on the end user doing all their beta testing?

Mat - 05/18/12 - 7:47am

So, when the Devinci Atlas test will be published? Can’t wait for it…

Tyler (Editor) - 05/18/12 - 11:24am

Mat – soon…couple more weeks probably. It’s a pretty sweet bike.

RoDe - 05/19/12 - 7:40am

MMhhhh I like CB pedals a lot never had an issue with them. CS is good too. But this product is not good now I’m not an engineer but that system will fail. That said I must say that all of the dropper post have some draw back. There are some companies who seem to have good grasp but none are perfect.

I would like to see a review of the Blacx post.

FANBOY - 05/19/12 - 6:24pm

@ Tyler
considering the overwhelming negative feedback on here, and most other sites, about CB product in general, not just their current failure with the Kronolog.

Any chance of getting someone from their company to comment? Not just on the ongoing saga of dropper posts, but on their entire system of releasing product without even beta testing?

I’m sure many others here would be interested to see their comments.

Dean - 05/26/12 - 12:49pm

Dropper posts are absolutely fantastic! However, having had the Joplin 3 which lasted all of 3 weeks first time round, the maintenance wasn’t worth the headache. Since seeing the Kronolog, I thought CB had nailed the design, and eagerly anticipated my Kronolog. I was very impressed with the presentation and packaging, and the post looks super overall.

However, after 1 ride of around 15km (cross country), the post no longer locks at the top. What it does is seem to lock, then if any weight is placed on the saddle, the post slides down abt 10mm and then locks. Unfortunately as it slides I can hear the grinding noise of wearing metal. And it is definitely not an installation issue, as I’ve watched and read all the info on installation.

Do not buy this post.

Innes - 06/10/12 - 8:40pm

Picked one up yesterday. EXACTLY the same issue as Dean. One ride (8.4 miles). Dean, what did CB do for you?

Dean - 06/14/12 - 9:19am

Hi Innes,

See the posting at: http://forums.mtbr.com/all-mountain/crank-brothers-kronolog-adjustable-seatpost-772741-13.html

CB service has been superb! They’ve replaced the post (it is currently on the way; I have a USPS tracking number.) I’ll update the above post once the new kronolog arrives.

Dean

Raf - 06/21/12 - 11:01am

Hi. I have noticed there is no oil in this seatpost. Is this correct? Does it work with air only? How is the post locked in one position? Is this done mechanically?

Thanks!!! Raf

Fabiano - 06/21/12 - 3:56pm

The Joplin 4 is very good ( 30.9 ; 560g w RC ). The system is mechanicaly very simple and eficient. And very easy to mantain too. I have one and the only issue was air leaking after 2 years use, easily fixed with the replace of the rubber o-ring that holds the air pressure. The only upgrade in this model could be a cap around the “head” of the shaft where that o-ring is placed. It could prevent dust and mood in that area, that cause the wear of the o-ring .
Here you can see how simple is the Joplin 4 :
http://vttplus.net/img/joplin/Joplin_1.pdf

Arcel - 07/31/12 - 3:18am

I got mine not even a month yet. every time I hit the bump seat post just drop on me got me annoy is something defect about it so I did call crank bro for warranty …

NatDog - 09/22/12 - 2:01am

I went against my better instincts and ppulled th trigger on the Kronolog because I like pretty things and like the internal travel adjustment capability. What a disappointment. I could not get the internal spanner ring off. I tried ice cubes, major brute and ovaled out the holes to twice thier original size. Now the bummer is I may not be able to return it. I appreciate the review here. Great pictures and I completley agree now about holding off on this purchase.

Post a comment:

Comment sections can be a beautiful source of knowledge, conversation and comedy. They can also get pretty ugly, which is why we've updated our Comments Policy. If your comment isn't showing up or suddenly disappears, you might want to check it out.