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Old 08-24-12, 05:20 AM   #1
Derailed
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Thoughts on Kore I-Beam Seat post and Compatible Saddle?

Anyone have an opinion on Kore's I-Beam seat post / saddle combination?

I'm looking to have some weight-saving options for my Dahon Mu Uno for when I travel by train and will be putting the bike in overhead luggage racks, yet riding for short enough distances that I'm willing to forgo the seat-post pump that came with my Mu Uno.

Two things give me pause:

1) Would this really save much weight?

The Biologic Postpump I have now is listed at 755 [g] on Thor's site, whereas the Kore I-Beam seat post is listed at 394 [g]. I can't find a weight for my saddle, but I figure even in the worst-case scenario an I-Beam compatible saddle wouldn't weigh any more. Accordingly, it seems like a lower bound on the weight savings should be 361 [g] (~0.8 lbs). Perhaps a light I-Beam saddle could bring this up to a total of close to a pound? Hmm... that best-case scenario might not be quite enough to justify the ~$100 expense...

2) Would an I-Beam setup lower the maximum height at which I can position my saddle?

I set my current saddle to right at the limit. Thor's site says the I-Beam post is 24" long with a 6" minimum insertion height. The Postpump is listed at only 23" long, but it doesn't specify a minimum insertion height. For comparison, however, I see that a standard Tern seat post is also only 23" long, but that it has a minimum insertion of only 4". If those numbers are the same for the Postpump, then I'd actually be an inch lower at maximum extension.


Hmm... It seems that in thinking this through to write this post I've just about talked myself out of it. That said, I'll keep an open mind in case anyone has any strong opinions in favor.
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Old 08-24-12, 05:44 AM   #2
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Depends how heavy you are.
The older SDG I beam seat post was even lighter and you can feel it flex a little whilst riding, perhaps the flex would reduce stress on the frame.
The weight saving is significant, I think the standard post is way overbuilt for most people and the pump hardly ever of any use.
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Old 08-24-12, 12:06 PM   #3
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check this out. i had this on my dahon speed tr. it's superlight. http://www.aliexpress.com/store/prod...533223162.html
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Old 08-24-12, 12:34 PM   #4
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Quote:
Originally Posted by Derailed View Post
Anyone have an opinion on Kore's I-Beam seat post / saddle combination?

I'm looking to have some weight-saving options for my Dahon Mu Uno for when I travel by train and will be putting the bike in overhead luggage racks, yet riding for short enough distances that I'm willing to forgo the seat-post pump that came with my Mu Uno.

Two things give me pause:

1) Would this really save much weight?

The Biologic Postpump I have now is listed at 755 [g] on Thor's site, whereas the Kore I-Beam seat post is listed at 394 [g]. I can't find a weight for my saddle, but I figure even in the worst-case scenario an I-Beam compatible saddle wouldn't weigh any more. Accordingly, it seems like a lower bound on the weight savings should be 361 [g] (~0.8 lbs). Perhaps a light I-Beam saddle could bring this up to a total of close to a pound? Hmm... that best-case scenario might not be quite enough to justify the ~$100 expense...

2) Would an I-Beam setup lower the maximum height at which I can position my saddle?

I set my current saddle to right at the limit. Thor's site says the I-Beam post is 24" long with a 6" minimum insertion height. The Postpump is listed at only 23" long, but it doesn't specify a minimum insertion height. For comparison, however, I see that a standard Tern seat post is also only 23" long, but that it has a minimum insertion of only 4". If those numbers are the same for the Postpump, then I'd actually be an inch lower at maximum extension.


Hmm... It seems that in thinking this through to write this post I've just about talked myself out of it. That said, I'll keep an open mind in case anyone has any strong opinions in favor.
I have the older version of the SDG I-Beam saddle that came from my Mu SL and is now on my Speed Duo and it works great. Should be the same as the new version? No? I really love the I-beam seatpost especially when it flexes. It does provide some suspension, a little less than my Thudbuster ST or more akin to a beam bike, on my 4130 chromoly Speed frame. Without it, it rides really harsh on chip sealed and potholes infested roads as I commute with my Duo everyday.

With the new I-beam, they sell an adapter to convert the I-beam rail to take on regular saddles and it will put the saddle much higher than the stock I-beam saddle for a fee, but you may loose the flex that the I-beam saddle provides. This will probably be your best bet if you're facing minimum insert issues and the ability to use your own favorite saddle is a plus.
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Old 08-25-12, 03:40 AM   #5
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I'm curious about this myself. My Tern Duo came standard with a Biologic seatpost pump. Not only is it heavy but it doesn't even work. Even if it did work, I don't think I'd ever have the opportunity of using it. So I've been thinking about switching it with a lighter seatpost. But if the weight savings is less than a pound then I don't think it'd be worth the price/hassle.
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Old 08-25-12, 03:51 AM   #6
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The seat post that vmaniqui mentioned is often available new on ebay at a very good price. I'd go for that as you can use a standard saddle.
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Old 08-25-12, 03:56 AM   #7
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Quote:
Originally Posted by Taipei Tony View Post
I'm curious about this myself. My Tern Duo came standard with a Biologic seatpost pump. Not only is it heavy but it doesn't even work. Even if it did work, I don't think I'd ever have the opportunity of using it. So I've been thinking about switching it with a lighter seatpost. But if the weight savings is less than a pound then I don't think it'd be worth the price/hassle.
It doesn't work? Are you sure you're using it correctly? Oh, and by the way, these seatposts on Ebay seem to be lighter than those Kore ones - 50mm shorter, but 120 grams lighter. It's 481 grams lighter than the Biologic seatpost, so you're basically saving a pound. Worth it for $134 though? Hmmm...

http://www.ebay.com/itm/TEAMSSX-New-...item43b2fb5279
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Old 08-25-12, 04:06 AM   #8
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A similar seat post has been selling on ebay.co.uk for around 20.
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Old 08-25-12, 05:56 AM   #9
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Originally Posted by chagzuki View Post
I'd go for that as you can use a standard saddle.
I can see the attraction of using a standard saddle but, from what I understand, part of the weight savings of the KORE system is from the attachment mechanism for the non-standard saddle -- the system saddle, presumably, can weigh less because of less material needed for the rails.

I just weighed my Postpump plus stock WTB / Dahon branded saddle, and I get 1.06 [kg]. If I use the Postpump weight from Thor of 755 [g], that would imply that my current traditional-rail saddle weighs 305 [g].

I see an I-Beam saddle on Thor's site with a stated weight of 239 [g]; combined with the I-Beam post (394 [g]), that would put me at 633 [g], a predicted savings of 427 [g], or, almost a pound.

I'm tempted...

As always, thank you all for the responses!
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Old 08-25-12, 07:20 AM   #10
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On ebay UK at the moment there's a Kore seat post new for 15. Perhaps they'll ship to the US if you request it.

The SDG seat post/saddle combo was ridiculously light, a shade under 600g according to my scales.
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Old 08-25-12, 07:50 PM   #11
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Quote:
Originally Posted by Training.Wheels View Post
It doesn't work? Are you sure you're using it correctly? Oh, and by the way, these seatposts on Ebay seem to be lighter than those Kore ones - 50mm shorter, but 120 grams lighter. It's 481 grams lighter than the Biologic seatpost, so you're basically saving a pound. Worth it for $134 though? Hmmm...

http://www.ebay.com/itm/TEAMSSX-New-...item43b2fb5279
that doesn't seem right. i wouldn't touch it for that price. as what chagzuki mentioned, it sells on ebay for much less. i got mine for about $18.
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Old 08-26-12, 09:11 AM   #12
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Originally Posted by Training.Wheels View Post
It doesn't work? Are you sure you're using it correctly? Oh, and by the way, these seatposts on Ebay seem to be lighter than those Kore ones - 50mm shorter, but 120 grams lighter. It's 481 grams lighter than the Biologic seatpost, so you're basically saving a pound. Worth it for $134 though? Hmmm...

http://www.ebay.com/itm/TEAMSSX-New-...item43b2fb5279
Yea it doesn't work. When I first opened up the pump, the whole thing was filled with oil. Very strange, took me awhile to clean it out. When I pump it, I feel air coming out of the nozzle. But when I hook it up and pump, nothing happens, it only drains the tire. It seems like the pumped air is escaping before reaching the tire. Perhaps I'm doing it wrong but I don't see any way that's possible...

For $18, I'll try a new seatpost, why not! But the problem is I'm in Taiwan. Are those seatposts available here?
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Old 08-26-12, 09:21 AM   #13
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Would any of these work? They all seem a little short...

http://tw.page.bid.yahoo.com/tw/auction/c63323925
http://goods.ruten.com.tw/item/show?21201069039205
http://goods.ruten.com.tw/item/show?21011027378787
http://goods.ruten.com.tw/item/show?11090219308093
http://goods.ruten.com.tw/item/show?21011027380072
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Old 08-27-12, 01:10 AM   #14
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will not work. what you need is size 33.9mmx600mm. since you're in taiwan you've got access to all these accessories. this will work although it's in china. http://item.taobao.com/item.htm?id=1...0_3k4_62985785

this is the pic of my $18 seatpost (gold color). size is 33.9mm x 600mm.
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File Type: jpg IMG_0154 A.jpg (100.9 KB, 93 views)

Last edited by vmaniqui; 08-27-12 at 01:16 AM.
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Old 09-14-12, 06:36 PM   #15
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check this out on bay. they have a seatpost now: http://www.ebay.com/itm/2012-GUB-Sea...item51a1327cb9
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Old 09-05-16, 11:11 PM   #16
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One benefit of 33.9x600mm is storage of inner tube

Inner tube in side dahon 33.9x600mm

I am able to insert a 20x1.7 - 2.10 (smaller is easier ) inner tube in side my Dahon 33.9x600mm seat post.

I fold it in half, attach a velcro and loop at the air\stem. Roll the inner tube at the middle and secure with a Velcro strip. Using a long wooden stick (dowel 3/16 from homedepod ), I push it against the first strap up the tube. At the end I attach a string for pulling out. I have enough room to store a rubber cement tube, a short metal saw blade, and a few repair patches. I use a candle wax on the inner tube to make it slide up easier and I have to replace the plastic cap.

A metal saw blade is a good use for scoring the inner tube instead of sand paper. Just break about 3 inches for this.

The inner tube rarely get used and need to be away from sunlight so this is a good place for this setup. I store the my hand pump and on the frame and levers under the seat.

I have tempted to change out the i-beam system when considering touring because i-beam is a new technology and few carry replacement. However, I have been using it for 5 years and it works with no problem.

Cheers

Last edited by resting; 09-05-16 at 11:17 PM. Reason: spelling error
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Old 09-09-16, 01:27 PM   #17
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My Dahon Formula S18 has a Kore I beam seat post and saddle. I dislike it as it is impossible to find other seats for it without ditching the seat post. I hate it.

Don't do it.
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Old 09-09-16, 02:04 PM   #18
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i saved almost a pound of weight (~400g) on my dahon mu uno by ditching the seatpost that came with the bike and replacing it with a controltech carbon fiber seat post i purchased from thorusa.

in my opinion it's a superior weight reduction solution to the KORE seatpost because the controltech seatpost is still equipped with a conventional saddle bracket can accept any old ordinary saddle.

also, the carbon seatpost is a flat black, which matches my mu uno quite nicely:

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Old 09-09-16, 08:07 PM   #19
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My Dahon Formula S18 has a Kore I beam seat post and saddle. I dislike it as it is impossible to find other seats for it without ditching the seat post. I hate it.

Don't do it.
You could always get the Kore seatpost rail adapter, then you could run any rail type saddle. There is one on ebay for under $20 .. normally they run around $35 new..

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Old 09-10-16, 12:33 PM   #20
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You could always get the Kore seatpost rail adapter, then you could run any rail type saddle. There is one on ebay for under $20 .. normally they run around $35 new..

I have one of these adapters and no matter how tight I tighten the adapter bolts, the seat does not stay in place because the bottom of the adapter eventually slips on the curved portion of the seatpost. The seat always slips all the way to the back. I'm not happy with it because of this.
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Old 09-10-16, 02:55 PM   #21
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I have one of these adapters and no matter how tight I tighten the adapter bolts, the seat does not stay in place because the bottom of the adapter eventually slips on the curved portion of the seatpost. The seat always slips all the way to the back. I'm not happy with it because of this.
Interesting, I never had problems with mine.. but that was back a few years.. I still ride the SDG I-Beam system (similar, but won't take the Kore Adapter) .. even worse nightmare for running rail seats as there was never an adapter.. good that I picked up a few I-Beam saddles that I liked back when..

If you haven't, you might try some carbon friction paste .. I use it on lots of interference fits that aren't carbon fiber..
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Old 09-16-16, 01:41 PM   #22
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Interesting, I never had problems with mine.. but that was back a few years.. I still ride the SDG I-Beam system (similar, but won't take the Kore Adapter) .. even worse nightmare for running rail seats as there was never an adapter.. good that I picked up a few I-Beam saddles that I liked back when..

If you haven't, you might try some carbon friction paste .. I use it on lots of interference fits that aren't carbon fiber..
Thanks for the tip. Never thought of using carbon friction paste on non-carbon parts. Don't use my Kore adapter any more but will use the friction paste next time I have metal on metal slippage.
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