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Wireless down and up dropper post??

yzf1999

Member
Mar 25, 2018
18
18
Illinois
Ok guys I have a question…I use my dropper post all the time at my favorite bike park. My analog dropper works perfectly, but I’d like to have a battery powered (blue tooth activated) dropper that will retract without me having to be setting on it using my weight to drop it. This would save me a ton of energy from having to lift myself back into the attack position every time I need it to be down. RockShox AXS Reverb only pops it back up not down. Does any know of a dropper that is battery operated down as well as up?? Thanks.
 
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steve_sordy

Wedding Crasher
Nov 5, 2018
9,098
9,589
Lincolnshire, UK
When I read "auto down and up dropper post" I thought you meant some GPS triggered device that would drop at the top of a hill, and rise at the bottom. I was composing a response in my head when I actually read your post. I now believe that you mean that you want to be able to trigger a down as a well an up.

I gave up trying to answer your post at that point and I am now seeking clarification.

It would be helpful if you could expand on the circumstances where you need a trigger to drop the saddle without your arse already being sat on it, or poised above it.

Your description of "This would save me a ton of energy from having to lift myself back into the attack position every time I need it to be down." We must have totally different riding needs because I cannot recall circumstances where my saddle was fully up and yet my arse was below the saddle height as something that I planned for, let alone requiring it on a frequent basis. Whenever that happens to me, I am usually in involuntary dismount mode. :eek:

I have just thought of one circumstance. The bike and I are stationary and, because of physical failings of mine, occasionally I need to drop the saddle to get my leg over the top tube and I have to lean on the saddle. Surely, you don't mean anything like that! :unsure:
 
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Polar

Well-known member
Jun 16, 2023
424
546
Norway
When I read "auto down and up dropper post" I thought you meant some GPS triggered device that would drop at the top of a hill, and rise at the bottom. I was composing a response in my head when I actually read your post. I now believe that you mean that you want to be able to trigger a down as a well an up.

I gave up trying to answer your post at that point and I am now seeking clarification.

It would be helpful if you could expand on the circumstances where you need a trigger to drop the saddle without your arse already being sat on it, or poised above it.

Your description of "This would save me a ton of energy from having to lift myself back into the attack position every time I need it to be down." We must have totally different riding needs because I cannot recall circumstances where my saddle was fully up and yet my arse was below the saddle height as something that I planned for, let alone requiring it on a frequent basis. Whenever that happens to me, I am usually in involuntary dismount mode. :eek:

I have just thought of one circumstance. The bike and I are stationary and, because of physical failings of mine, occasionally I need to drop the saddle to get my leg over the top tube and I have to lean on the saddle. Surely, you don't mean anything like that! :unsure:
I'm sure some wouldn't mind the last circumstance you mentioned everyone has different preferences
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,628
5,104
Weymouth
When I read "auto down and up dropper post" I thought you meant some GPS triggered device that would drop at the top of a hill, and rise at the bottom. I was composing a response in my head when I actually read your post. I now believe that you mean that you want to be able to trigger a down as a well an up.

I gave up trying to answer your post at that point and I am now seeking clarification.

It would be helpful if you could expand on the circumstances where you need a trigger to drop the saddle without your arse already being sat on it, or poised above it.

Your description of "This would save me a ton of energy from having to lift myself back into the attack position every time I need it to be down." We must have totally different riding needs because I cannot recall circumstances where my saddle was fully up and yet my arse was below the saddle height as something that I planned for, let alone requiring it on a frequent basis. Whenever that happens to me, I am usually in involuntary dismount mode. :eek:

I have just thought of one circumstance. The bike and I are stationary and, because of physical failings of mine, occasionally I need to drop the saddle to get my leg over the top tube and I have to lean on the saddle. Surely, you don't mean anything like that! :unsure:
Nice try at sorting this !! I would also add that an auto down ...ie you press a rocker and the seat drops.........could well be considered dangerous if hit by mistake!! I usually only have the dropper at full extension on access routes to trail heads, but anywhere properly offroad i slam it about halfway...............then only fully slammed on gravity descents. So any auto down would need to be controllable to that extent. Meanwhile as @steve_sordy suggests all of that seems completely unnecessary when I have an ass with 70KG above it to the job of slamming it:D
 

DieBoy

Active member
Jul 14, 2023
144
218
EU
Ok guys I have a question…I use my dropper post all the time at my favorite bike park. My analog dropper works perfectly, but I’d like to have a battery powered (blue tooth activated) dropper that will retract without me having to be setting on it using my weight to drop it. This would save me a ton of energy from having to lift myself back into the attack position every time I need it to be down. RockShox AXS Reverb only pops it back up not down. Does any know of a dropper that is battery operated down as well as up?? Thanks.
No.

A dropper post is in its "natural" state up. To depress it takes at least 30-40kg of 'weight' (gladly accept corrections on the figure here), so around at least 350 Newtons worth of force, applied for the length of the stanchion.

You'd need a fair sized motor or solenoid for that, especially as you'd want it to be moving faster than 1mm per second. You'd then need a large battery to power it, capable of a full depress multiple times per charge.

In short, totally unfeasible for size, weight, cost, and reliability for a feature I suspect almost nobody in the world actually needs or wants.
 

yzf1999

Member
Mar 25, 2018
18
18
Illinois
Well if someone could come up with one it would be a game changer in my book...I see no advantage to the wireless up only droppers when it saves no energy for the rider.
 

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
1,870
2,936
La Habra, California
Well if someone could come up with one it would be a game changer in my book...I see no advantage to the wireless up only droppers when it saves no energy for the rider.

You might be on to something. Someone should build a "Riser Post." The air piston would have the pressure on the OTHER side. When you want the saddle up, squeeze it between your thighs and lift. When you want the saddle down, you hit the remote button and the saddle slams downward. BAM! Totally sick, yo.
 

Hattori-Hanzo

Well-known member
Apr 10, 2023
428
568
UK
I seem to recall a dropper post that allows you to have two height settings on the same lever, half press the lever and it goes to position 1, fully depress the lever and it goes to position 2.
Can't remember what make it was though.

You still have to manually lower the dropper though
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,628
5,104
Weymouth
You might be on to something. Someone should build a "Riser Post." The air piston would have the pressure on the OTHER side. When you want the saddle up, squeeze it between your thighs and lift. When you want the saddle down, you hit the remote button and the saddle slams downward. BAM! Totally sick, yo.
...the kit would include velcro patches on the saddle and some that you sew onto your shorts so you have grip to raise the saddle. .........hang on....I just thought of a few problems that may cause
 

Jokipea

Active member
Apr 4, 2023
9
31
Scotland
When I first read the OP I thought it was a bit of a pisstake but you're serious FFS.
Jeez, how much energy does it take to stand up on pedals again after using your arse to push the saddle down?
How do you even manage to actually ride a bike?
This has got to be a whoosh...
 
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yzf1999

Member
Mar 25, 2018
18
18
Illinois
You don’t understand the terrain…in a 13 mile loop I probably have to use the dropper over 50 times. That’s adds up in the energy usage.…also i guarantee in the future this style post will exist, it’s the logical evolution of the dropper.
 
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Astro66

Active member
May 24, 2024
353
637
Sydney Australia
Yeah sorry, I agree with the OP. Sometimes I want to move the dropper just a little up or down. It's really hard to do when you are bouncing over rough terrain, as your butt bounces up and down and you keep over-shooting the position you are trying to get to.

I don't find it energy zapping. It just distracts me from hitting the perfect line, as you try and set the perfect seat position, for the terrain you are currently running.

This is how I would design it. A pneumatic piston that slams up and down really quick like the current systems. Then a separate button that does finer increments using an electric stepper motor, like on the electronic derailleurs.

So it's a pneumatic piston held within a electric motor drive piston. 2 actions. 2 controls. One coarse control. One fine control.

It's literally combining a electronic dropper with an AXS derailleur. Come on SRAM. Get to it ...... :p
 

whitymon

Active member
Nov 29, 2023
290
151
Europe
There is something out there for 1k but not sure it allow you to do a full slam/full up, plus the required insertion is more important.


In any case, having a motor in there would make it heavier but mostly way too slow (for at least one direction) which is why they come up with some kind of second tiny chamber.

We would really need to picture the issue here as on all I can ride, this was never a real issue. I mean it is way more exhausting to keep myself on knees bent for few minutes than having to pull the lever place my but on the saddle and slam it back later on.
On Enduro loop, I also tend to never put my butt on the saddle except if it is a climb then I do not waste any energy reaching top to slam it back, I let my body and gravity do it.

As for dropper micro adjustments on the fly, I need to think about it, I never ever had the need better anticipation might be the idea?

Everyone is and ride different stuff but there is a need for a big market or race need to be a thing and I honestly don't see it, could be wrong.
 

p3eps

E*POWAH Elite World Champion
Subscriber
Dec 14, 2019
1,983
2,405
Scotland
Anyone ever considered drilling 2 holes in their rim and putting 2 tubes in?!

On a more serious note... if you want it to be able to go in both directions automatically, then it's going to need a motor (as mentioned above), which is going to take time to go up and down.

I've had an AXS dropper for 5 years now. The thing I like about it is it's instant response to the click, and the fact you can actually just touch the button for a millisecond and drop the saddle a couple of mm.
When I'm on fire roads and most climbs I like my saddle at full extension, however if it's a technical climb, I like it to be down a fraction so I have a bit more stability - especially if I need to put a foot down.

Like most, I rode for years without a dropper, and you just got used to shifting your body about to cope with it.
If you were going to a gnarly DH trail, you'd whip an Allen key out of your pocket, loosen the collar, then slam the post. At the end of the run, you'd have to raise it again.
The dropper post surely must be one of the best improvements to MTB in the last 10 years?! There have been plenty of refinements to it... but does it really need re-invented?
 

whitymon

Active member
Nov 29, 2023
290
151
Europe
Just remember the AXS is just a tiny little thing that do a tiny move to let the air pushing back the post. It is not a gearbox for up and down :D as it would be incredibly slow.

AXS dropper is cool but too heavy for its purpose, 760g vs 525 for OneUp, it does not make any sense for me compared to a cable actuated one, it use less thumb power true but the drawback is too much for me, anticipation is way better than hitting a button.

I get we all loves tech stuff, I live the idea of the AXS dropper, really, but this is definitely something people do not need if they read carefully the trail - at the very least I am glad this is useless to me.
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,628
5,104
Weymouth
The OPs primary concern is to save energy and given there are no dropper posts that meet his needs maybe some advice on how to use a dropper could help.
Firstly the fully extended position only serves one purpose and that is to achieve the most efficient pedalling position. On an emtb it is less critical since the motor provides a proportion of the power so a partially slammed seat position can also be used. At the same time a fully extended dropper has disadvantages in making rider plus bike centre of weight more top heavy. So for me anywhere offroad a fully extended dropper is rarely used.
For any gravity runs the post is slammed. For me on forest rides most of the time I am stood on the pedals with the post slammed except on climbs. For more cross country type rides the dropper is mostly about one third slammed except on the boring bits
 

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
1,870
2,936
La Habra, California
There is something out there for 1k but not sure it allow you to do a full slam/full up, plus the required insertion is more important.

Dude! That is certainly... innovative. As lame as it sounds, I couldn't resist reading about it and watching some videos.

The saddle does move up and down with the press of a lever. But it's not a regular seatpost that you can put on your bike. It's part of the frame that comes on that particular BMC model. The power to actuate the device is from compressed air. You have to pump up your frame to 200 psi. Even in the videos, the movement isn't super-fast. The benefit is that beginners don't need to worry about smashing their balls. The travel is a whopping 80 mm.
 

timo2824

Member
Dec 27, 2023
48
65
USA
You don’t understand the terrain…in a 13 mile loop I probably have to use the dropper over 50 times. That’s adds up in the energy usage.…also i guarantee in the future this style post will exist, it’s the logical evolution of the dropper.
Get a gym membership and start working out 😂.

On the post it's totally possible, but would involve an actuator and gear system that would add quite a bit of weight.
 

yzf1999

Member
Mar 25, 2018
18
18
Illinois
Think of the dropper post as a solenoid where the seat post is the metal shaft and the part in the frame has the windings to create the electro magnet to move the post…I know everyone thinks it’s stupid, but most people thought the E-bike was stupid till it came out and the advantages of them were experienced first hand.
 

timo2824

Member
Dec 27, 2023
48
65
USA
Think of the dropper post as a solenoid where the seat post is the metal shaft and the part in the frame has the windings to create the electro magnet to move the post…I know everyone thinks it’s stupid, but most people thought the E-bike was stupid till it came out and the advantages of them were experienced first hand.
I work with solenoids, one with the power to overcome a spring that holds a grown human up with 170mm of travel would be a hunk of metal 😂. Probably add at least 20lbs to a bike.
 

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