A 27.2 mm Electronic Dropper Seat-Post. Ideas?

[Stefan Mikes]

When I used to own an e-MTB, I was delighted with the applicatons a dropper seat-post was giving me. It was especially useful while riding downhill or in a rough terrain. With descents, I used to drop the seat so I could move my body weight far rearwards. With the rough terrain, especially during sand riding, the lowered saddle allowed me confidently riding with my centre of gravity down, and with the possibility to immediately support my body with planting the feet on the ground when needed. (I tried that on a demo Levo SL to my great satisfaction).

I have used a suspension seat-post on my Vado SL for three years, and the Redshift ShockStop has been indeed excellent. However, I converted to wider tyres and tubeless meanwhile, which allowed me riding at a lower inflation pressure; the tyres have increased the level of comfort to the level I could swap my suspension seat-post for...

A dropper seat-post.

I have used a 350 mm seat-post. The max insertion depth of the seat-post is 200 mm. The seat-tube is 27.2 mm internal diameter. I'd like an electronically activated seat-post because I wouldn't like to route yet another cable inside the busy downtube of my Vado SL. Of course, I'd welcome a dropper with the greatest travel possible.

Suggestions? Experiences?

@Prairie Dog: Could you tell me more about the SRAM Reverb AXS? What size have you used? What travel? Could you take a pic of the lever?

P.S. I did a little research. The long travel Reverb AXS seat-posts are deadly expensive. However, I could buy a 50 mm travel AXS XPLR at a reasonable price. Oh, but the Remote is not included?!

 

[jabberwocky]

Does the bike not have internal routing for a dropper? No experience with wireless, I'm sure it works, but cable actuated droppers are way cheaper and running the cable isn't hard (assuming the bike has internal routing). Plus I love the Wolf Tooth levers.

I had a first gen Reverb (2012-2013 era) and it was very unreliable. It was repaired by Rockshox twice and on the third death I replaced it with a OneUp which has been solid. Hopefully Rockshox has fixed the reliability issues I had. I don't remember what my YT Decoy came with but its been solid too.

 

[Stefan Mikes]

Does the bike not have internal routing for a dropper?

No way. The port in the top tube will not allow the third cable to pass. And I don't want the external routing.
Unfortunately, the electronic dropper costs an arm and a leg!

 

[Prairie Dog]

@Prairie Dog: Could you tell me more about the SRAM Reverb AXS? What size have you used? What travel? Could you take a pic of the lever?

P.S. I did a little research. The long travel Reverb AXS seat-posts are deadly expensive. However, I could buy a 50 mm travel AXS XPLR at a reasonable price. Oh, but the Remote is not included?!

Sorry for the confusion. What I meant to say is that I don’t have the Reverb AXS as I didn’t feel like dropping $1K Cad down for a wireless dropper (pardon the pun). I’m sticking with the stock cost effective X-Fusion Manic for now which appears to be the same dropper on the Levo.

A couple others that I'm not familiar with are the Trans-X and KS LEV Circuit.

https://www.bikeradar.com/reviews/components/seatposts/tranz-x-edp01-wireless-dropper-post-review

https://www.bikeradar.com/reviews/components/seatposts/ks-lev-circuit-dropper-seatpost-review

 

[jabberwocky]

No way. The port in the top tube will not allow the third cable to pass. And I don't want the external routing.
Unfortunately, the electronic dropper costs an arm and a leg!

Oh man, thats annoying. Yeah, electronic it is, unless you're willing to drill out the frame somewhere or zip tie the cable to the top tube and run an external dropper.

 

[PDoz]

He has 3 choices if the extra cables don't fit

1 wireless SOMETHING - personally , I'd go wireless shifting and run dropper cables through the port instead of shifting cables . Ie spend the extra $ on something that enhances the riding experience. We're getting lots more choices in wireless shifting, and every time I've ridden a bike equipped with it I'm tempted to spend the $.

2 external cables , not really a choice for a vain rider.

3 actuation under the nose of the saddle - ks eten do a 27.2 but it's only 100 mm drop. We could run a go fund me campaign to buy him one and then a pay to view site ( stephan stacks?) with footage of him fiddling around in his groin then crashing. Donate the funds to running this site?

As for cabled dropper posts , makes sure they are easy to service and you can adjust air pressure easily ( under the seat using a shock pump) .
Unfortunately one up don't cater to 27.2 -they are a great dropper if you want maximum travel , and I've had a much better run from them than specialized / giant / tranz x .

 

[Stefan Mikes]

1 wireless SOMETHING - personally , I'd go wireless shifting and run dropper cables through the port instead of shifting cables . Ie spend the extra $ on something that enhances the riding experience. We're getting lots more choices in wireless shifting, and every time I've ridden a bike equipped with it I'm tempted to spend the $.

That's an interesting idea! Although I'm happy with my current mechanical drivetrain, removing a derailleur cable to route the dropper cable sounds good. @PDoz what is an electronic drivetrain system which does not require the SRAM UDH and is good for MTB/gravel?

3 actuation under the nose of the saddle - ks eten do a 27.2 but it's only 100 mm drop. We could run a go fund me campaign to buy him one and then a pay to view site ( stephan stacks?) with footage of him fiddling around in his groin then crashing.

Too dangerous! Besides, the insertion depth for the relevant 27.2 mm dropper post is 243 mm, while I only have 200 mm available inside the seat-tube.

When I research cable dropper posts, I experience difficulty to find a 27.2 mm one withe the insertion depth not greater than 200 mm. I think I'd give the whole idea up. It looks it would be simpler to buy a new hardtail or gravel e-bike with a dropper post, haha!

 

[PDoz]

That's an interesting idea! Although I'm happy with my current mechanical drivetrain, removing a derailleur cable to route the dropper cable sounds good. @PDoz what is an electronic drivetrain system which does not require the SRAM UDH and is good for MTB/gravel?


Too dangerous! Besides, the insertion depth for the relevant 27.2 mm dropper post is 243 mm, while I only have 200 mm available inside the seat-tube.

When I research cable dropper posts, I experience difficulty to find a 27.2 mm one withe the insertion depth not greater than 200 mm. I think I'd give the whole idea up. It looks it would be simpler to buy a new hardtail or gravel e-bike with a dropper post, haha!

I wouldn't have a clue about gravel bike gearing, sorry

 

[Stefan Mikes]

I wouldn't have a clue about gravel bike gearing, sorry

In my case, MTB drivetrain is used. Currently, M5100.

 

[6zfshdb]

That's an interesting idea! Although I'm happy with my current mechanical drivetrain, removing a derailleur cable to route the dropper cable sounds good. @PDoz what is an electronic drivetrain system which does not require the SRAM UDH and is good for MTB/gravel?

These electronic shifting systems from Archer are reasonably priced, easy to install and work with almost any derailleur. There is also a power cable adapter option for Bosch systems:

Archer Components Electronic Shifting for Every Bike

Electronic shifting systems for every bike. 100% compatible with any rear derailleur. Any number of gears. SRAM, Shimano, TRP, Campy, Box. We work great with everyone! This is the only electronic shifter you need for your bike.

archercomponents.com

I now have them on all my bikes and was able to remove all the shifter cables. I've been using them for 3 seasons now and have had zero problems.

AFAIF, they offer international shipping.

 

[Stefan Mikes]

These electronic shifting systems from Archer are reasonably priced, easy to install and work with almost any derailleur.

Thank you! I am more and more negative to do such modifications. I have realised no system would actually match my Vado SL unless I want to spend a lot for a 50 mm XPLR seat-post and the remote. The situation with electronic drivetrain is even worse unless Shimano eventually releases an MTB electronic Di2.

I would use a dropper post in exceptional situations, so it makes no sense to go that way, and I am as happy with my M5100 11-51T, 11-speed drivetrain as I only can be

Next time I'm buying an e-bike it could be either a Creo 2 or a new version of a Tero (not X), so I can always walk my Vado SL down a steep sandy descent

 

[PDoz]

Thank you! I am more and more negative to do such modifications. I have realised no system would actually match my Vado SL unless I want to spend a lot for a 50 mm XPLR seat-post and the remote. The situation with electronic drivetrain is even worse unless Shimano eventually releases an MTB electronic Di2.

I would use a dropper post in exceptional situations, so it makes no sense to go that way, and I am as happy with my M5100 11-51T, 11-speed drivetrain as I only can be

Next time I'm buying an e-bike it could be either a Creo 2 or a new version of a Tero (not X), so I can always walk my Vado SL down a steep sandy descent

If you get a chance, ride a bike with electric shifting or a higher end lever / mech / cassette.

My giant has an m5100 lever but xt mech, it is perfectly adequate ....but you change gears a lot when riding and I realise that when getting back on it . This might be a wear and tear issue - I hate to think how many km of abuse that bike has endured. It might even be 12 vs 11 sp ( all our other bikes are 12 sp with sram ) .

For perspective, if I hop off an electric shifting bike onto my sram 12 sp levo sl, THAT feels ? 10%? sloppy. Yet hopping off the levo sl to the giant with m5100 would be ?30%? sloppy. It's hard to put a figure on this, and very subjective - but more than the difference you feel by dialling in the mech of fitting a new chain / cassette.

 

[Stefan Mikes]

If you get a chance, ride a bike with electric shifting or a higher end lever / mech / cassette.

I have demo ridden an Epic 8 Expert, SRAM GX AXS Transmission. A wonderful experience. Perhaps in the future