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Dropper post Giant Liv Lust XS


I was wondering if you could shed some light on a suitable dropper post for my Giant Liv Lust3 full sus in XS.

I’m only 5ft so both me and the bike are pretty small. I’ve done the measurements I think I need but can’t work out if it’s possible to find a small enough dropper post.

- The diameter is 30.9
- The max insertion from seat post collar to it hitting the bolt in the frame is 150mm
- The seat collar to centre of the saddle rails is 180mm (seat collar to top of the post is 150mm)

Any ideas? I’m guessing I’m going to struggle with the overall length...

I’ve attached a photo of my bike so you can see the frame I’m talking about.

Thanks in advance for any help!


  • reaperactualreaperactual Posts: 1,183
    edited May 2020
    Highly recommend checking out Chain Reaction Cycles. They do the Brand X dropper post in stealth (internal routing) and an externally routed version in various travel options. Really good reviews and a very good price compared to some brands.

    Off memory sounds like the 125mm travel will fit you and your frame. To be sure there is a diagram on image 8 so scroll through pics. on the listing page.

    Has all the measurements you need and from there you can work out the stack height (exposed portion of post) for a comparison with your measurements or check out Q+A on internal routed post as I know for a fact someone worked out stack heights and stated them on there, because it was me!
  • reaperactualreaperactual Posts: 1,183
    Apologies nellransom for previous and useless post!

    Just had a closer look at your frame design. Your probably right that you don't have much insertion room at 150mm. No dropper that I can think of would fit inside such a short Seat tube insertion depth, sorry!
  • steve_sordysteve_sordy Posts: 2,438
    edited May 2020
    So that is 330mm for the complete seatpost. (180 + 150).

    The 30.9 diameter 105mm travel dropper (Brand -X Ascend II)

    The main body is 207, so it will fit into your seat tube with 207-150 = 57mm sticking out. That is plenty in there for safety.
    Then there is a collar on top of the main body that is 33mm tall, taking you to 230mm (207+33)

    Then you get the 105mm travel, which in the fully extended position makes 230 + 105 = 335mm. On top of that you have the seat clamp which is 55mm to the centre. That gives you an overall extended height of 335+55 = 390mm.

    That is too tall for your 330mm. It is too tall by 60mm. You don't have to use all the travel of course, but for spending your money you will only get 105-60 = 45mm of usable travel.

    You can fit and use the Brand-X dropper, but you will only get 45mm travel. In case you think "fine! I'll have that!" be aware of this:
    I had a dropper that fully extended was just 10mm too high for comfort. In use, I could never get the dropper to return to the place I wanted when on the move. The saddle was either too high or too low. Both were a nuisance and took the edge off the ride. Trying to find the right height whilst pedalling over a bumpy trail was never easy. You may decide that you can live with this, I couldn't. But I was fortunate that the Reverb dropper failed soon after bike purchase and I was able to be specify a replacement that was 25mm shorter, that sorted the problem! You have been warned.

    Have a look around to see what else you can get, some droppers come with 80mm travel only and the body is also shorter, so they may fit and work for you! But they may not have a 30.9mm diameter body to fit your seat tube. The good news is that they will be smaller diameter and you can shim them. You can buy seat post shims of all thicknesses and materials, or you can make your own. all is not lost! :)
  • steve_sordysteve_sordy Posts: 2,438
    I have just spotted this 85mm travel 27.2mm body diameter dropper by Brand-X

    It is usable, but still puts the saddle too high but only by 20mm this time. It means that you will get 65mm of travel. It is also a stealth dropper and the cable comes out of the bottom, which may be a problem.

    If you decide to give it a go, then you will need a 27.2-30.9mm shim. The shim material will be 1.85mm thick, so it is unlikely that you will be able to make one yourself unless you have access to machinery. But you will be able to buy one.

    Good luck, and if you find a solution let us know, others may have the same problem.
  • JBAJBA Posts: 2,852
    Giant do a 295mm Contact Switch dropper post that should fit. However, I suspect that will not offer much travel. Maybe 65mm?
    The KS Lev comes in shorter lengths as well. The 295mm would fit and possibly the 335mm.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Sonder Broken Road 2021¦ Giant Revolt Advanced 2 2019 ¦ Giant Toughtroad SLR 1 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • steve_sordysteve_sordy Posts: 2,438
    Someone somewhere usually has the perfect answer. Well done JBA! :)
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