blimly

I am looking for an extra long 33.9mm seatpost to use on my Dahon Classic III folding bike.

I am looking to replace the heavy chromed-steel telescoping seatpost with a single piece alloy post.

The challenge is that I am a tall rider and need something longer than the standard 580mm seatposts sold by Dahon and others.

QUESTION 1:

Other than the Tern 33.9mm telescopic seatpost, has anyone seen a good single-piece (non-telescoping) seatpost option?

One potential option I found is the LitePro 650mm aluminum seatpost being sold online through Amazon and by various sellers on Ebay.

However, I have scoured the internet (and written to a few online sellers) and can't seem to get an answer as to the distance from the bottom of the seatpost to the minimum insertion line. I worry that (based on all the product photos I've found) the min-insertion is further up the post, meaning I won't gain as much effective length as the 650mm measurement would otherwise imply.

QUESTION 2:

Has anyone used one of these LitePro alloy seatposts? Could you let me know the distance from the bottom of the post to the minimum insertion line?

rhenning

I have 3 of these seat posts and all have worked fine for several years. From the rails of a Brooks B17 I have 15+ inches showing and they could be a bit higher. Roger

Kabuto

The minimum insertion on the 580mm Litepro seatpost I have is 150mm, and judging from the pictures on Alibaba it looks like the 650mm seatpost has the same amount of minimum insertion. Maximum weight limit is also 80kg. The minimum insertion of the 580mm Creek Thudbuster, Tern and Dahon seatposts I have is 100mm, so compared to them, the Litepro 650mm only gets you 20mm more height.

blimly

Thanks both for the quick response. That's exactly the info I needed.

So, it sounds like the 650mm LitePro gives only about 500mm of height from the minimum insertion line to the rails.

That'll make it about 40mm too short for the height at which I need my saddle on this bike.

Unless anyone knows of any other seatposts that are long enough (which, thus far, I've been unable to find anywhere), I'm guessing the Tern telescopic seatpost may be my only option.

Kabuto

Update: I ended up buying a Litepro 650mm seatpost, because I was really hoping it would give me an extra 20mm of height and put me in the perfect position, and it arrived today.

Much to my disappointment, the minimum insertion of the Litepro 650mm seatpost is 160mm, not 150mm. So you only get a measly extra 10mm compared with a standard Dahon or Tern seatpost. MAJOR DISAPPOINTMENT

The seatposts are from left to right: Dahon seatpost from Speed D8 > Litepro 600mm > Litepro 650mm > Tern Stasis by Syntace seatpost

drzdave58

i think U could squeeze out that extra 10mm without any major problem couldnt you?

Nemosengineer 

Sometimes you have to bite the bullet and build your own seatpost. I had to do this to get a quality seatpost that actually fit a vintage frame. This is done by cutting the seat mount off the post of an existing seatpost, machining it to a socket configuration and welding it to a suitable piece of 6061 T651 (T651 is the weld friendly variant of T6) aluminum tubing of the desired length. A photo of my modified seatpost is shown below. Please note that there are many things to consider before undertaking a fabrication of this type as your safety is a direct result of your design choices, also note that certain alloys of aluminum are not considered weldable (2000 and 7000 series alloys).





: Mike

Kabuto

Lol there's always that option. But I was actually hoping I'd have that option plus the extra 20mm (or even 30mm). Oh well. You win some, you lose some.

abone

Xootr Swift, although discontinued, still show a 34mm x 640mm seat post available on their website. You will have to click and select the xxl size in the drop down. Not sure how much height is avail. They are quite helpful if you call.

https://www.xootr.com/swift-seat-post.html

Doctortee

Hi,
I have the same problem with a seatpost being too short. I also found only the two alternatives (telescopic seatpost and litepro). I‘m surprised about the different minimum insertions. Normally, the overall recommended minimum insertion is 100mm, though. In my case an additional hull is inserted in the tube of the frame, where the seatpost is inserted. The length of this hull is also 100mm. So, to insert the litepro farer than these 100mm wouldn‘t make any sense as there is no additional clamp force to bring on the resulting 60 mm of the litepro tube. So, I will give the litepro a chance. I also need every mm of the seatpost length....
Maybe you also have this inserted hull. But also if not, I would give the 100mm a try, if you don‘t weight to much (in my case 83 kg).

tomtomtom123

you could switch to longer crank arms. Or use the Brooks flyer/imperial. The springs on the flyer raises the height by quite a lot. Probably a couple of centimeters.

Doctortee

Thanks,
longer crank arms would be too expensive and don‘t give me the needed extra in height. I decided to build an own telescopic seat post by buying a 600mm/33,9mm seatpost, a 350/27.2mm seatpost, an adapter and a clamp. That costs a little over 30 €, and maybe itīs also a little lighter than the Tern one...