13 best hydraulic seat posts
Hydraulic seat posts, also known as dropper seat posts, are innovative components used in cycling that have gained popularity among mountain bikers and other off-road cycling enthusiasts. These seat posts are designed to allow riders to quickly and easily adjust the height of their saddle while riding, without having to dismount or use tools.This feature is especially valuable when transitioning between uphill climbs and downhill descents.
Here are some key points about hydraulic seat posts:
1. Dropper Mechanism:
Hydraulic seat posts consist of a hydraulic cartridge inside the seat post tube. When activated by a lever usually mounted on the handlebar, the hydraulic mechanism lowers or raises the saddle height as desired by the rider. The range of adjustment varies between models but usually allows for several inches of movement.
2. Remote Activation:
Most hydraulic seat posts come with a remote lever mounted on the handlebars, allowing riders to adjust the seat height on-the-fly, enabling them to focus on the trail without distractions.
3. Improved Maneuverability:
By lowering the saddle during descents, riders can lower their center of gravity, improving stability and maneuverability. This is particularly advantageous when navigating challenging terrain or technical descents.
4. Increased Confidence:
Being able to quickly lower the saddle provides riders with more confidence, especially in steep descents and jumps. It allows for a more aggressive riding style, enhancing overall performance.
5. Compatibility:
Hydraulic seat posts come in various diameters to fit different frames. It's crucial to choose a seat post that matches the diameter of your bike frame's seat tube.
6. Maintenance:
Proper maintenance is essential to ensure the smooth operation of hydraulic seat posts. Periodic checks, cleaning, and, if necessary, bleeding the hydraulic system, are important to maintain consistent performance.
7. Weight Consideration:
Hydraulic seat posts are generally heavier than traditional fixed seat posts due to the added hydraulic components. However, advancements in technology have led to the development of lighter models, catering to weight-conscious riders.
8. Popular Brands:
Various reputable cycling component manufacturers produce hydraulic seat posts, offering different features and price points. Some well-known brands include RockShox, Fox Racing Shox, KS Suspension, and specialized cycling companies like Thomson and Crankbrothers.
In summary, hydraulic seat posts have revolutionized the cycling experience, especially for off-road enthusiasts. Their ability to swiftly adjust saddle height enhances rider confidence, maneuverability, and overall enjoyment of the sport. Riders can easily adapt to changing trail conditions, making them a valuable addition to any mountain bike setup.
Below you can find our editor's choice of the best hydraulic seat posts on the marketProduct description
Description:
Product Category:Seatpost
30.9 / 31.6 wire controlled lifting seat tube
Color: Black
Material: al7075
Specification: 43 * 42mm
Stroke: 100mm
Wall thickness: 3mm
Degrees: - 5 ° + 18 °
Length "external wiring 375mm internal wiring 400mm
Diameter: 30.9 / 31.6mm (actual OD, no adapter)
Weight: 30.9/31.6 inner wiring 653 / 679g
30.9/31.6 external wiring 628 / 650g
Applicable to road bike, mountain bike, DH, FR, am, XC
Packing list:
1 * Seatpost
Note:Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.
- Made from quality material, which is not only wear resistant but also stable.
- Built to greatly strict quality control standards, so it has a stable and excellent performance.
- It is easy and convenient to install, it just costs you a little time on its installation.
- [Friendly Tips]:1> This suspension 27.2 seat post is designed to absorb the shocks from the road suck as hitting a pothole ,it is not for making the ride like sitting on a limousine ,If you need more comfortable riding,please consider advanced remoted control or hydraulic seat post.2> Seatpost clamp is not included
- [Specification]:Material: 6061 Aluminum alloy barrel& Steel Mount, durable.Seatpost Clamp Mount Diameter: 22.2mm(O.D.).Length: 350mm.Diameter:27.2mm(real outder diameter ,no adapter)
- [Damping type]:Built-in Coil Spring Suspension, Travel: 40mm adjustable preload suspension travel.Tube Thickness: 3 mm.Weight: Approx 458g(27.2mm)
- [Wide Application]:Fit For beach cruiser bikes,mountain bikes,tankdem bikes,comfort bikes,Cyclocross Bikes, Electric Bikes, Folding Bikes, Hybrid Bikes, Kids Bikes,Time Trial/Triathlon Bike, Touring Bike, Town Bike, Track Bike, Tricycle, Unicycle, Urban Bike - Fixed Gear Bikes and BMX bikes etc.,
- [How to Choose the Size]:Check the Original Seatpost Size Marked on the body ,choose the same size as the original one.Inquire the bike frame maker to get the further informationMeasure the inside diameter of the frame tube(considering Operator,measuring tool , Temperature,etc,normally it is not accurate, )
User questions & answers
Question: | Can you adjust the spring tension |
Answer: | Small it is for smaller cat. Mine is a kitten |
Question: | Do I need to also purchase a "seatpost clamp |
Answer: | My cat is a fatty, she weighs 14 pounds and is able to lay in the sling without the thing topping over. Hope that helps. |
Question: | Does this work for an ebike |
Answer: | Yes Very good pass |
Question: | What is the weight limit for this type of seat post? I recently bought another premium brand and it was too soft for 200 lbs |
Answer: | No, it is not legal for California. |
Product description
Q: How can I determine if I received the correct size seat tube?
A: The size is engraved on the bottom of the seat tube, you need to look at it under sufficient light.
Q: How do I know what size seat tube I need to buy?
A: Please check our last picture (the seventh), which contains information on how to measure the size of the seat tube.
Q:What you need to pay special attention?
A:the size between 30.9mm and 31.6mm difference is not big, but if it is different from your bicycle size, it still cannot be used normally, so please measure before buying! !
If it is measured that your seat tube is 30.9mm, please do not buy a 27.2mm or 31.6mm seat tube, because it will not be suitable
Q:The ad title says the size is 27.2/30.9/31.6, but the ad text (which changes depending on what picture you click) gives different sizes - which is correct?
A:Tips: Please choose your correct size according to the ad text (which changes depending on what picture you click). The title contains all the sizes we sell, which is not accurate enough. Please refer to the first description for the correct size.
Feature:
♫ The hydraulic seat Tube have excellent shock absorber and buffering pressure performance
♫ aluminium alloy 6061(tube part)
♫ Anti-corrosion
♫ anti-oxidation
♫ Suitable for most road bike, fixed gear bicycle,
mountain bikes,downhill bike, track bike, MTB, BMX, DH, etc
- specification:30.9*350mm Suspension Seatpost, Made of high-quality aluminum alloy 6061
- Advantage : The new spring Hydraulic Seat Tube adopts internal shock absorption mode to make riding comfortable. The screw inside the seat tube can finely adjust the stroke rebound speed and reduce the vibration effect for bike.
- Installation: Installation is easy, just loosen the old seat and remove the seatpost, then bolt the seat to the new seatpost and install it into the bike frame.
- Must pay Attention:The seat post outside diameter is 30.9mm ,please measure your bike and choose the right model.Please double check whether it fits your bike size before buying! Our last picture has a measurement method
- Tips: Please choose your correct size according to the ad text (which changes depending on what picture you click). The title contains all the sizes we sell, which is not accurate enough. Please refer to the first description for the correct size.
Product description
30.9/31.6 Bicycle Dropper Seatpost Manual Control Lever Height Adjustable Hydraulic, 100mm Travel x 375mm
Features:
Material: Aluminum alloy 6070-T6, durable and practical to use
The mountain bike manipulator controls the lifting seat tube, the operation is more convenient and the lifting seat rod frame is solved in one fell swoop
Anodized surface treatment, polished wire drawing, CNC molding technology.
The product adopts a seal ring design to effectively protect the inside of the seat tube. It is more sealed to fit the seat tube, preventing rain, cement, sand and dust from entering. It also protects the oil inside from leaking and maintains lubrication.
Pipe diameter ruler, clear scale and safety mark Specifications:
Type: Hydraulic dropper seat post
Color: Black
Package include: 1 x 30.9MM dropper seatpost, 1 x Seatpost 30.9 I.D. / 31.6 O.D. Shim.
- Original diameter of dropper seatpost 30.9, the diameter of the 31.6mm seatpost is the effect after using the reducing sleeve, a conversion kit is required to install 31.6.
- Package include: 1 x 30.9MM dropper seatpost, 1 x Seatpost 30.9 I.D. / 31.6 O.D. Shim.
- Dropper seatpospost 100mm travel, length 375mm, Offset 18°, Weight 1.4 lb.
- Adjust the height manually by hydraulic pressure, and stretch it several times before use, easily adjust the height of the seat tube to solve your troubles of difficult adjustment of the seat tube.
- Material: Aluminum alloy 6070-T6, anodized surface treatment, polished wire drawing, CNC molding technology.
User questions & answers
Question: | Do you make a 27.7 mm version |
Answer: | That is the seat post clamp. |
Question: | Can you adjust the speed that it goes up/down |
Answer: | Worked with my e bike. Just be sure to order Correct diameter. |
Question: | do you have 400 mm post |
Answer: | I have the 30.9mm version. It does not specify a weight limit but I am over 200lbs and it works fine for me. It only moves when I hit a hard bump. |
- Please check which size you need before place an order.
- Material : Forged Aluminum 6061 Max Travel 100mm
- Diameter 31.6mm Offset 18mm
- Weight 640g
- You could adjust travel by the manual control lever
Product description
Material: aluminum alloy
Size: 27.2mm/31.6mm
Weight: about 632g (27.2mm) / about 706g (31.6mm)
Control: Wire control
Length: 440mm
Lifting stroke: 0-100mm
Application: mountain bike
Installation operation:
1. Confirm that the size of the middle tube of the frame is suitable for the lifting seat tube (27.2/31.6mm)
2. Confirm that there are no burrs, metal shavings or sand in the middle tube of the frame that may cause scratches
3. Install the lifting seat tube to the frame in the correct direction, and the outlet of the control line faces the rear of the frame
4. Install the control handle set on the handlebar
5. Use cable ties to properly fix the control wire to the frame
6. Pry the handlebar left and right to confirm that the control line will not interfere with the steering
Operation note:
This lifting seat tube has 3 fixed height adjustable
1. Lower the seat cushion height: lift the buttocks slightly away from the seat cushion, keep pressing the control handle while pressing the seat cushion down with your weight; once the seat cushion starts to move, release the control handle, and the seat cushion will continue to drop to the next position. "The click is automatically locked.
2. Raise the height of the seat cushion: Lift the buttocks slightly away from the seat cushion, continue to press the control handle while slowly raising the buttocks to make the seat cushion rebound automatically. Once the cushion starts to move, you can let go of the control handle. When the cushion continues to rise to the next position, it will make a "clicking sound and automatically lock it."
Packing List:
1 Piece Bike Seat Post
- Hydraulic line control lift seat tube bicycle seatpost.
- High quality aluminum alloy material, lightweight, durable and strong.
- Multi Sizes for different needs(27.2mm, 31.6mm).
- Smoothy surface, classic pillar style design, exquisite workmanship, nice touch feeling.
- Suitable for most old style bicycle saddles with clamp. ( Note: If the height segment is not fastened smoothly or cannot be fastened, please adjust the tension fine adjustment knob on the thread set.
Product description
Features:
New spring suspension seat tube, the use of internal shock mode, makes riding comfortable. Made of good quality aluminum alloy, solid, durable, wear-resistant and corrosion-resistant. The screws underneath the seat tube can micro-adjust stroke rebound velocity. The installation is easy, no need complex operation. Perfect accessory fits for mountain bike, road bike and so on.
Specification:
Item Type: Mountain Bicycle Seat Rod
Material: Aluminum Alloy
Color: Black, Silver (Optional)
Options: 27.2mm Seat Rod Black, 31.6mm Seat Rod Black, 27.2mm Seat Rod Silver
Length: Approx. 350mm/ 13.78 inch
-01 Caliber: Approx. 27.2mm/ 1.07 inch
-02 Caliber: Approx. 31.6mm/ 1.24 inch
-03 Caliber: Approx. 27.2mm/ 1.07 inch
Packing List:
1 x Mountain Bicycle Seat Rod
Note:
1. Please kindly confirm the fitment and replacing OE number before ordering to make sure this item is perfectly fit.
2. It is easy to install, but professional installation is always highly recommended.
WE SELLER HAS TO SAY:
As an reliable seller, we promise that 100% money refund about damaged product during delivery. We are committed to provide the best customer services to our customers. If you have any questions, just contact us and we will give you the most satisfactory solution.
- ☆【Aluminum Alloy】: Made of high-quality aluminum alloy, strong and durable. Lightweight and durable. Polished and anodized, never rust.
- ☆【Fitment】: Options: 27.2mm Seat Rod Black, 31.6mm Seat Rod Black, 27.2mm Seat Rod Silver, Length: Approx. 350mm / 13.78 inch.
- ☆【Internal Shock Absorption】: The new spring suspension seat tube adopts internal shock absorption mode to make riding comfortable. The screw under the seat tube can finely adjust the stroke rebound speed.
- ☆【Easy Installation】: Installation is easy, just loosen the old seat and remove the seatpost, then bolt the seat to the new seatpost and install it into the bike frame.
- ☆【Pay Attention】: Be sure to measure the actual diameter required before purchasing. Saddle clips are not included, please purchase saddle clips separately as needed.
User questions & answers
Question: | What is maximum rider weight |
Answer: | Hello, in the bottom of the post you'll find a threaded adjuster. Use an allen key, to screw it in (increase pressure) or out (decrease pressure). |
- Please check which size you need before place an order.
- Material : Forged Aluminum 6061 Max Travel 100mm
- Diameter 30.9mm Offset 18mm
- Weight 612g
- You could adjust travel by the manual control lever
Product description
Need a dropper that doesn't kill your budget? KS aims to please with the Race-i. This pocket-friendly dropper is built to get the job done with a two-bolt micro-adjust head, and stanchion tube that doubles as an open bath hydraulic cartridge body for smooth and reliable support.
- Diameter: 30.9mm, 31.6mm, 34.9mm
- Offset: zero
- Travel: [30.9mm, 31.6mm] 75mm, 100mm, 125mm, 150mm, 170mm, 190mm, [34.9mm] 125mm, 150mm, 170mm, 190mm
- Dropper: yes
- Claimed Weight: 549g
User questions & answers
Question: | Does it include the remote lever to activate the dropper |
Answer: | This link is the 30.9 cm / 31.6 cm dropper seatpost. |
Product description
The PNW Components Cascade Dropper Seatpost pays homage to the Cascade mountain range, home to some of the best riding in the Pacific Northwest. Featuring reliable coil sprung internals, tidy external cable routing, and multiple travel options, this post is an absolute workhorse that provides dependable up and down service for miles and miles to come. The 150mm and 170mm travel options have been updated with larger diameter stanchions that makes them both stiffer and lighter, as well as an added DU bushing to combat side-to-side seat wobble. Together these changes improve the post's reliability even further, giving you some much-needed peace of mind when you're out in the mountains, miles away from civilization.
- Material: aluminum
- Diameter: 30.9mm, 31.6mm
- Length: [125mm travel] 406mm, [150mm travel] 449mm, [170mm travel] 489mm
- Offset: 0
- Travel: 125mm, 150mm, 170mm
User questions & answers
Question: | Total length |
Answer: | Bicycle dropper seatpost manual control lever up/down adjustable hydraulic, 100mm travel x 375mm. |
Product description
-------------------------------------------------------------------------------------------
[Friendly Tips]:
1> :this suspension seatpost is designed to absorb the shocks from the road suck as hitting a pothole ,it is not for making the ride like sitting on a limousine ,If you need more comfortable riding,please consider advanced remoted control or hydraulic seat post
2>:Seatpost clamp is not included
--------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------
How to Choose the Size:
1>Check the Original Seatpost Size Marked on the body ,choose the same size as the original one.
2>Measure the inside diameter of the frame tube(normally it is not accurate, considering Operator,measuring tool , Temperature,etc.,)
3>Inquire the bike frame seller to get the further information
--------------------------------------------------------------------------------------
Material: Aluminium Alloy
Color Options: Black
Rail Width:44mm ,
Offset:10mm ,
Travel:40mm,
Length above min insertion line: 250mm
Damping:Coil Spring
Diameter: 25.4mm/27.2MM/28.6MM/30.8MM/30.9MM- - - - - (real outer diameter , no adapter)
Length: 350 mm
Weight: approx 502g(25.4*350mm)
560g(27.2*350mm)
597g(28.6*350mm)
607g(30.9*350mm)
635g(31.6*350mm)
Fit for: Road bike ,MTB ,Mountain bike ,DH ,FR
How to adjust soft and hard status?
use M6 allen wrench to adjust bike Seat post bottom
- Constructed of ultra light and strong T6 aluminum alloy. Light weight, never rust(ISO 9001,14001).This 25.4 mm suspension seatpost is designed to absorb the shocks from the road suck as hitting a pothole ,it is not for making the ride like sitting on a limousine ,If you need more comfortable riding,please consider advanced remoted control or hydraulic seat post
- Seat Post Size: 25.4mm ,Length :350mm , no adapter , real outer diameter
- Damping:Coil Spring ,Rail Width:44mm ,Offset:10mm ,Travel:40mm,Length above min insertion line: 250mm
- Weight: approx 502g(25.4mm)
- How to Choose the Size(3 choices): Check the Original Seatpost Size Marked on the body ,choose the same size as the original one. Measure the inside diameter of the frame tube(normally it is not accurate, considering Operator,measuring tool , Temperature,etc.,). Inquire the bike frame seller to get the further information
User questions & answers
Question: | Not sure what (30.8)30.9 in the description means, while 30.9 is the ordering option. Will any size option fit a seat tube meant for a 30.8 post |
Answer: | Glad to help you! Our bike seatpost can withstand 120kg at maximum. |
Question: | How do you adjust the tension |
Answer: | Original diameter of dropper seatpost 30.9, the diameter of the 31.6mm seatpost is the effect after using the reducing sleeve, a conversion kit is required to install 31.6. |
Product description
SEATPOST SUNLT SUSPN 25.4x350 noCLMP SL
- Adjustable pre-load design
- Coil spring suspension
- Collar adjustment for play removal
User questions & answers
Question: | How do you adjust the seat post tension |
Answer: | The (30.8)30.9 is the diameter of the seat post in mm. If your existing post is 30.9, then buy the (30.8)30.9 size. If your seat post measures 30.8, then still buy the (30.8)30.9 size. Some bikes may have a nominal size post of 30.8mm, and the Ganopper actual seat post diameter is 30.9mm, but the difference in size is only 0.1mm/0.004in...ergo, it will fit as a replacement, though insertion into your frame may be a little tight. Just be sure you buy as close to your existing post size as possible - don’t buy a 27.2 and expect it to fit a 30.8. |
Question: | Will this help on a MTB terrain to soak up some bumps |
Answer: | There is a screw at the bottom of the post that adjusts the tension of a spring. |
Question: | so what is the minimum height of the seat above the seatpost top with this installed? 2nd time asking! Please reply |
Answer: | 170 mm |
Question: | How do I know what size I need |
Answer: | No, you will need to purchase your own lever. It does however include the cable and cable end that is properly fitted for the post release valve. |
Product description
Comfortable to ride
- Comfortable to ride
User questions & answers
Question: | Do they make a 30.9 mm |
Answer: | There is a spring that runs through the whole shaft.On the bottom of the shaft is a slot to adjust the tenshion.screw it towards the top incresses tenshion.reverse eases tenshion. |
Question: | Is this good for someone around 200 pounds? (90 kilograms |
Answer: | Works like a shock absorber.Does the job for me.Hope this helps |
Question: | can this be adjusted lower? Seems to be as low as it can go and seat is still too high for me at |
Answer: | I was just sent this question for the 1st time, so not sure about your 1st inquiry. The minimum length that this post sticks out of the bike cylinder is 4.5". Note the top inch of this 4.5" length is where the seat attaches to the pole so the resulting minimum length of the pole sticking out of the bike cylinder is 3.5". If you need further clarity please let me know. |
Question: | Is it adjustable or retractable |
Answer: | Best bet is to take your bike to a shop and let them measure. The difference in size is very small and hard to see the stamp on the shaft. |
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