Folding Bikes - Any Feedback on the Biologic Postpump Seat Post

I saw this on Dahon's Web site and am considering ordering it -

Has anyone tried this and does it really work as well as they say it does? I have a rather long commute and would feel better having a pump with me that could actually work in a pinch.

I had one on my Matrix. The pump itself is pretty cool (though it does get grimy). My suspicion is that on that bike, it didn't extend as far into the seat tube as it should have, and the resulting flex may have contributed to the frame cracks I experienced.

I could be totally wrong about this, and I'm not an engineer (thank god). But I would at least compare its length to whatever you're using now.

I have one on my Dahon SmoothHound. I've even had occasion to use it in two emergency situations. Works very well. I'm surprised other mfgs don't do something similar.

Thanks for the feedback, especially about the lack of extension. I'm on the short side, so my seat post stays pretty far in, but I wouldn't want to do anything to harm my baby (a Dahon Speed Pro TT). I will probably order it, but will make sure to compare it to my current seat post when I get it.

I have one on my Dahon SmoothHound. I've even had occasion to use it in two emergency situations. Works very well. I'm surprised other mfgs don't do something similar.

It's almost the perfect way to provide an on-board pump isn't it. Maybe Dahon have patented the idea or something. You'd think it was too good an idea to miss if it was freely available.

My P8 came stock with one. The pump itself is great. Easy to use and powerful.

Problem is the handle is prone to falling out from the bottom of the post while you're riding (you can find numerous forum posts about this). It's dangerous. There are a number of ways you can rig it to not do this but as far as I know Dahon has still not fixed it.

It's almost the perfect way to provide an on-board pump isn't it. Maybe Dahon have patented the idea or something. You'd think it was too good an idea to miss if it was freely available.

A quick search for US patents assigned to Dahon shows only one old patent. Strange. I would expect them to have more many more.

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=dahon.ASNM.&OS=AN/dahon&RS=AN/dahon

http://www.pat2pdf.org/patents/pat5269550.pdf

BTW, the patent seems to be very restrictive (just the main claim is more than half a page long) and does seem to be relevant to most of their existing models (I am not a lawyer).

Kam

The new one comes with a screw-on cap. Mine never falls off.
OP's picture shows the old one like folderster's.

I like it but I like having a Thudbuster more. All my bikes have a rack bag or under seat pouch and I'd rather have the Thudbuster and carry a small pump with me.

Now if they'd just make a Thudbuster with an airpump inside, that would be cool.

John

love the pump; powerful. As mentioned screwtop fixes the old fallout problem. Only issue is the weight it adds, but I like the post as a whole so have left it on.

its pretty long enough for the 20 inch bikes ....
http://www.thorusa.com/dahon/accessories/seatpost.htm
the 26 inch one is a different diameter and much shorter ( not terrible short but obviously shorter around 320 mm versus the 550 mm for the small wheeled bikes )

the new one indeed have a screw cap and are muchniocer in that respect than the old ones
good pump although I do prefer the thudbuster and a small pump as well

thor

The pump is effective for emergency pumping but it's a screw on pump and you lose air when unscrewing the pump from the tire.

The pump is effective for emergency pumping but it's a screw on pump and you lose air when unscrewing the pump from the tire.

I feel the same way - it's irritating screwing this onto a schrader valve, but the pumping seems to be fine and I filled to 80 psi with no difficulty. I am curious how stiff the tube will be after a few years. I haven't tried this on a presta valve yet, it comes with an adapter to do both.

I personally like the design of the Topeak Road morph, with the built in gauge, and same pumping style (against the ground). But it's not integrated into anything and a little large.

My 2007 Mu P8 came with the postpump seat post too. I have never used it to inflate a tire, but I do expect it will be handy if I ever have to fix a flat on the road. At home I use my air compressor instead.

This one does not have the new screw cap, but only once has the pump end dropped down to drag on the ground.

Recently, one of the two set screws that hold the innards in place came unscrewed from its place. That interfered with raising and lowering the seat post until I discovered the problem and tightened it back into place.