KIDS DROPPER POSTS
Dropper Posts start to make sense in 24 inch bikes for some kids. If you are riding a lot of ascending/descending terrain, constantly lowering your kiddos' seat post can be a pain. The droppers below should have you covered for both internal and external routed bikes. We use these posts and can attest the lever is an easy push and lowering post with light weight riders works well. Pay attention to insertion length and post diameter.
One up Dropper V2
New sizes with a 90 and 120mm version that can be shimmed down to 70mm or 100mm. This lets you increase travel as kiddo grows. Its a nice smooth lever and easy actuation of the post so our nine year old has no problems getting on with the post. I think most avg weight 8 year olds and up would do great on this post. In fact you can run lower air pressure and probably get away with a 6/7 year old on it. Comes in 30.9, 31.6 and 34.9 diameters. 90, 120, 150, 180, 210 and 240 mm lengths which can all be shimmed down 20 mm. Shortest insertion and lowest stack in the business. Our go to post.
MSRP: $249 (199 without lever) USD | Where to buy: Jenson USA
KS LEV Si and Integra Droppers
The LEV-Si offers everything you need and nothing you don’t. Internal cable routing, black, hard anodized running surfaces for long performance. Available in 65, 75, 100, 120, 125 and 150mm travels and 27.2, 30.9 and 31.6mm diameters with KGSL Alloy remote. We used a 75mm (30.9) version of this post on our Maxwell 24 for our 7 year old, worked great! This is a great post to use for the 5-10 year olds as it functions on low air pressures and is an easy lever actuation.
MSRP: $239-269 USD | Where to buy: Jenson USA | Amazon (75,30.9) | Amazon (100-150, 27.2-31.6)
Brand-X Ascend Kids Dropper Post
So amazing we now have multiple options for kids specific dropper posts! Brand-X aka TranzX have come up with this light actuation internally routed 70mm drop post. Only available in 27.2 diameter, the idea is to use a shim if you a bike with bigger seat tube diameter (i.e. 30.9). Minimum insertion length is 80mm (including the actuator – this is 114mm of post). Total post length is 315mm. Designed for the 6-12 crowd, this post works for riders 44 lbs up to 88 lbs (20 KG to 40 KG), and check out the price.
MSRP: $135 USD | Where to buy: Chain Reaction
PNW Components Fern Dropper Post
New for September 2021, PNW is the first to do a Kids Specific Dropper! Travel is 90 mm of drop on a 27.2 diameter. The thought is you can shim for larger diameter seat tubes (30.9). They also chose external routing so the post can fit the most amount of kids bikes possible. Its a specific light action cartridge that will work with any PNW lever. Min/max rider weight is 44-110 lbs. That's right a 22 lb kiddo has enough weight to lower this post. Full insertion length is 198 mm and a total length of 348 mm.
MSRP: $199 USD | Where to buy: PNW Components
KS LEV Dropper Seat Post External routing
You get the same easy actuation as the internally routed posts form KS. This is the one for upgrading kids bikes that don't have internal routing.
MSRP: $259 USD | Where to buy: Jenson USA
It looks like CRC/Wiggle have stopped international shipments. Do you know of an alternate source for the Brand-X ascend or a similar inexpensive kids post? Rider is ~65 pounds, frame in question is 30.9, and supports internal routing but I would be comfortable shimming the post.
My 40kg son is too light to drop a Brand X Ascend II (150mm) post. He doesn’t need the full 150mm travel so I’m looking at the 100mm post, but unsure if the shorter travel makes it more likely that he can drop it at his weight. Any experience of this? Do shorter-travel droppers typically need less weight to drop?
No, its more the specific dropper than the length of travel.
Has anyone tried the RockShox Reverb Stealth 1X?
How does it compare to a OneUp dropper?
Can it be used by a kid with a weight of 30 kg (60 lbs)?
Lately new dropper posts from “DXC” brand popped up on bike24 with great prices. These are probably just rebranded Tranz-X/Brand-X posts.
I bought the DXC DP/TWO 200mm version for myself, and it’s pretty good weight, easily adjustable travel down to 35mm, with 5mm steps, low collar height and the price is awesome.
I was also looking for a dropper for my younger one to put on a 24″, and bought the DXC DP/THREE I.50 27.2x50mm. It’s really nice, the weight is just 415g and the price is great, but unfortunately my 28kg daughter cannot drop it by sitting on it and I will probably return it. Seems like I need to go for the Brand-X Ascend Kids, but it costs 66% more.
Do you possibly know the weight of the Brand-X Ascend Kids?
Verified with another dad… The PNW is just a rebranding of the Tranz-X 27.2 … His 75lb kid has trouble getting the post to drop and replaced with a KS (adjustable air)
OneUp 27.5 looks to use the same sealed cartridge.
…bummer too, cause the tranz-X 90mm kitsuma post is the exact size needed for my 49lb 8yo
Interesting… My 7 year old ran the PNW Fern all last year on his 20″ Fluid FS 20 and had zero problems at 55lbs. I wonder if its the leaver? My son has the PNW loam leaver
My 45lb son has absolutely no problem actuating and lowering the PNW Fern Kids dropper.
Which dropper remote do you recommend for kids 5 and 7? I have KS droppers going on their bikes this week and need advice on remotes for small hands. thanks
The KS lever works great and we have good success with the oneup lever on the KS posts for the kids too.
Thanks for running this awesome page. I have come back to it time and time again over the past few years. Have you guys honed in on any particular levers that are more advantageous for kids?
The one-up lever works great. We have used it on multiple brand posts.
Brand-X (Chain Reaction Cycles house brand) also offers their Ascend Kids’ MTB Dropper post with remote for $110. These are manufactured by TranzX from what I could tell, just like PNW and some other brands. The post has 70mm of travel with a total length of 315mm and a full insertion length of 114mm. The post is only available in 27.2mm with internal routing. The suggested rider weight is 20kg (44 lbs) to 40kg (88 lbs). We have been using one on my sons 24″ bike for several months and performance has been flawless.
Nice, we were waiting on this one to become available. Thanks for sharing.
Thanks for the tip. Great website. I have a lead on A LEV si second hand. I’ve never installed one of these and wondering if you know if a 100MM would be the right size for a 4’10” kid / 75 lbs?
It depends on kiddo’s inseam (book between legs standing against wall), insertion length (available on KS site) of post and and seat tube length available for post (drop a tape measure in seat tube).
Thanks Colin. I should have asked if it would fit a Woom Off 6. Something tells me no internal droppers work on that bike. Any external post recommendations?
Keep the rubber side down!
BC
Double check but I believe the woom off 6 is 27.2 seat post which would work for a external KS LEV (comes in 65, 100 and 120 mm drop).
The LEV models are perfect for kids, it has an air valve for adjustment.
Light weight riders(kids) will be able to compress it.
The LEV is External Route,LEV Ci, LEV Integra, LEV Si, is internal route.
27.2x65mm,100mm,120mm.
30.9/31.6/x65mm, 80mm, 100mm, 125mm, 150mm, 175mm, 200mm.
34.9x80mm, 100mm, 125mm, 150mm, 175mm, 200mm.
2020 models will now be available without remotes, bringing the price point lower.
Thanks for the specs Mike
The OneUp V2 doesn’t work with my 42 pound 6 year old. KS Lev Si does.
yep, oneup for 9/10 year olds and up (65 lbs plus).
Can your then 9yro push down the post with his hand before getting on?
Never tried as he can drop the seat while riding but it takes a little more with timing compared to a KS Lev or kids specific post. I’de just go a nice smooth action quick release and normal post if dropping by hand was the plan…save some money, weight and maintenance.
Colin, I think the issue is those times of expected dismount when the kid didn’t get the seat down before dismount. Now the seat is up and hard to get on. I often need to push it down for my guy to get on.
Ah I see, my eldest at nine could push down with hand. The KS LEV integra was definitely easier than the oneup. He could still do it but it was more effort.
The OneUp doesn’t have a exact number for activation force, but it’s going to be in the area of 50 lbs they e-mail me.
Also on OneUp droppers with a diameter of 30.9 or greater, they will have an air adjustable cartridge and if you air the post down a little lower than 250PSI (say 200-225psi), it will take a bit less weight to “drop”– the trade off is that it will also rise slower. On the 27.2 droppers, the cartridge is non-adjustable and will take ~50 lb to compress.
My 9yr old just moved off an KS Lev SI post that had a very light activation force…but was still tough when she was 7 and <45lbs. Now she's ~55lbs and can work the OneUp just fine and I set it to 220 psi for her. She can't work it at 250 psi charge.
I had my son using the OneUp v2 since he was 6yo (he’s on the small side too) and on a 20″ bike. Running the air pressure below the minimum worked fine for him. When dismounted he could lean on the seat with his elbow and put his weight into it to bring it down without issue.
One up offers the lowest stack height and short insertion length is very helpful on the 20″ bikes, plus the ability to shim as they grow or move onto a bigger bike is very helpful.
Also check out Lyne Components. Similar to PNW.
Running a 110 (27.2dia, external routing) dropper for my kid on a Specialized Riprock 20.
Post will be moving to his Transition Ripcord soon.
Where can you find Lyne droppers in the USA?
Anyone know is the external ks lev can be slammed all rhe way down to the collar or does it interfere with the external cable interface?
Seems to be the right choice for my 7 year old daughter however worried already about the additional stack height (her current seat is only 30mm stack). I think the ks is 55mm plus if it needs 2 – 3 cm that’s a huge difference from her currently 1cm raised seat.
What seatclamp size is it on the rimrock do you know. I think ill just get a quick release?
its 27.2 seat post diameter I think…so 28.6 Seat tube diameter.