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Old 01-07-09, 12:07 PM   #1
dschwarz
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I need a new stem for my DT Mini handlepost, any suggestions?

Hi,

I have a 2009 Downtube Mini and just traded a wobbly handlepost for a good one (thanks Yan.) The replacement handlepost is a 2008 model. It pairs with a handlebar that is welded to a vertical tube, about 11" long and 1" outside diameter that fits into the handlepost.

The handlebar is about 2" narrower than my stock 2009 handlebar, which is not good. My nice Ergon GR2 grips will not fit on the right side; between the brake lever, twist shift and grips, I'm out of room! I don't want to cut the grip or go back to nasty cheapo grips. I'd rather replace the handlebar and stem.

So now my question.. does anyone know where I can get a new stem that'll work? It needs to have the 1" outside diameter, needs to be long enough, and it'd be a bonus if it can work with my stock handlebars. If not, I'm OK buying new bars.

The Dahon Revolve Stem
is the only thing I've seen online that looks like it might work. I've emailed Thor to get the exact dimensions on the stem.

Thanks!
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Old 01-07-09, 02:12 PM   #2
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There are also Ergon shorty grips. Selling the ones you have and buying the shorties might be another option.

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Old 01-07-09, 02:50 PM   #3
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If by "shorty grips" you mean the "twist shift compatible" grips, those are the ones I have. The grip itself is about a hand-width wide (plus space for the bar-end)
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Old 01-07-09, 04:26 PM   #4
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The grip itself is about a hand-width wide ...
Are you a time-traveler from the year DCCC ?

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Old 01-08-09, 09:20 AM   #5
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Quote:
Originally Posted by dschwarz View Post
Hi,

I have a 2009 Downtube Mini and just traded a wobbly handlepost for a good one (thanks Yan.) The replacement handlepost is a 2008 model. It pairs with a handlebar that is welded to a vertical tube, about 11" long and 1" outside diameter that fits into the handlepost.

The handlebar is about 2" narrower than my stock 2009 handlebar, which is not good. My nice Ergon GR2 grips will not fit on the right side; between the brake lever, twist shift and grips, I'm out of room! I don't want to cut the grip or go back to nasty cheapo grips. I'd rather replace the handlebar and stem.

So now my question.. does anyone know where I can get a new stem that'll work? It needs to have the 1" outside diameter, needs to be long enough, and it'd be a bonus if it can work with my stock handlebars. If not, I'm OK buying new bars.

The Dahon Revolve Stem
is the only thing I've seen online that looks like it might work. I've emailed Thor to get the exact dimensions on the stem.

Thanks!

What happened to the 2009 stem post and handlebar?
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Old 01-08-09, 02:13 PM   #6
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What happened to the 2009 stem post and handlebar?
The 2009 handlepost was defective; the excess play was there from day one. It couldn't be fixed. The 2009 handlepost is much different than the '08, it has an integrated stem that cannot be removed, so the stem would not have been transferrable.

I still have the stock '09 handlebar, and hope to use it with a new stem.
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Old 01-08-09, 02:20 PM   #7
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Update

I heard back from Thor at thorusa.com, the Dahon revolve stem is 1 1/8" OD and works differently besides, so it is not a solution.

Jur suggested I buy a length of 1" OD aluminum aircraft tubing (cheap, light, strong) and use that with a threadless stem. This is the only workable solution I've found so far. I don't have any experience selecting or installing threadless stems, so I have to do my homework on that.
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Old 01-08-09, 03:40 PM   #8
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I still have not seen the 2009 Mini up close -- the Downtube site had few pictures of the 2009 ... at least ones that I could find -- so I am trying to picture what you are talking about.

(1) There is the stempost base with the quill that gets inserted into the head tube.

(2) There is the stempost with a stem welded to the top that allows the handlebar to adjust vertically.

(3) There is a handlebar that you actually hold onto.

So you write that there is a stem welded onto the top of part #2? Interesting. And the handlebar is on the inside of the fold ... that isn't what I would expect.

I seem to recall that Yan used a stubby BMX stem on the 2008 model.
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Old 01-08-09, 03:49 PM   #9
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BTW, Jay Gaerlan might have that stubby BMX stem you are looking for.

http://gaerlan.com/dahon/stem.htm
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Old 01-09-09, 12:56 AM   #10
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My 2009 stem was also very wobbly in stock form. I had to glue a plastic tab to the folding interface to get the tolerances right. Much better now...no wobbles.
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Old 01-09-09, 09:35 PM   #11
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Thanks for all the responses. Invisiblehand, I assume you're referring to the 50mm stem for $24.95 at Gaerlan. Looks good, I think!

Here are some photos of my Mini "before" and "after" the changes so you can get a better sense of what I'm talking about.

First, before. This is my 2009 Mini, mostly stock. You can see the 2009 handlepost here. It is comprised of the bottom part with the quill, the folding hinge, the handlepost extending above the hinge, then finally a nonremovable, adjustable height stem at the top. The handlebar bolts onto this. The fact that the handlebar is mounted directly over the stem makes for a very compact fold, and allows the stem to fold down between the halves of the bike.



Now, after. Here is the bike after some customizations and installation of the 2008 handlepost. The handlebar is welded to the vertical tube which curves down into the handlepost. It folds to the outside of the bike because the handlebars are offset from the stem. I can completely remove the handlebar, and I'm thinking of removing it and replacing with a length of 1" OD aluminum tube + a threadless stem + my stock 2009 Mini handlebar or some other inexpensive handlebar.



Last, a cockpit view of the 2008 handlepost + handlebars. The right side is so crowded with brake lever, twist shifter, and Ergon GR2 grip, that the brake lever is pushed onto the curved portion of the handlebar -- it doesn't pull back straight and it doesn't engage as well as it should. I have switched the left and right brake levers, so that my front brake lever is on the left and it engages properly.



Something tells me I should have just kept shimming up my 2009 handlepost.
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Old 01-09-09, 10:10 PM   #12
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Wild. Did the placement of the bar change when you switched from the 2009 to 2008?

I found that with the 2008 base, my knee would occasionally hit the stempost. To get the reach I wanted, I needed a 130mm stem. After it was all said and done, I simply put the old post back on and reversed the handlebars such that the sweep moves away from me. The extra two inches or so does it for me; although I don't have a lot of surface area at the end of the bar. I have considered looking for really short bar ends but it might make the fold difficult.
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Old 01-09-09, 11:05 PM   #13
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You could take a hacksaw to the 1" riser to which the handlebar is welded, then clamp a 1" stem onto that, finally a nicer-looking flatbar. (I think a flatbar looks better than the riser.)
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Old 01-09-09, 11:10 PM   #14
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Wild. Did the placement of the bar change when you switched from the 2009 to 2008?
When you say "placement of the bar" I assume you mean the location of the handlebar? Yes, that changed when I switched to the 2008, because of the new handlebar/vertical tube included with the 2008 handlepost.

I have never experienced any bumping into the stempost (my limbs are probably a lot shorter than yours; I'm 5'5")

If you are looking for really short barends I can highly recommend the Ergon GR2s (assuming your handlebars are wider than mine, of course) They are a huge improvement over the stock grips and the bar ends didn't really interfere with the fold when I had the 2009 handlepost installed. Now, of course, they still don't interfere with the fold, but they do increase the overall width of the folded bike.
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Old 01-10-09, 08:11 AM   #15
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What are the inner diameters of the clamp the arrow is pointing to, on the 2008 and 2009 models respectively?
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Old 01-10-09, 09:06 AM   #16
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When you say "placement of the bar" I assume you mean the location of the handlebar? Yes, that changed when I switched to the 2008, because of the new handlebar/vertical tube included with the 2008 handlepost.

I have never experienced any bumping into the stempost (my limbs are probably a lot shorter than yours; I'm 5'5")

If you are looking for really short barends I can highly recommend the Ergon GR2s (assuming your handlebars are wider than mine, of course) They are a huge improvement over the stock grips and the bar ends didn't really interfere with the fold when I had the 2009 handlepost installed. Now, of course, they still don't interfere with the fold, but they do increase the overall width of the folded bike.
It looks like the total reach to the handlebar might be shorter than before. Although I suppose that it would depend on how much you raise the handlebar.

The problem with the Ergon grips is that it forces the shifter and brake lever too far inwards for my taste. But I concur regarding the original grips. I swapped them for a nicer set from Ritchey and cut the one for the right hand to adjust the reach for the shifter. Otherwise, I like the Ergon grips in other applications.

Because I flipped my handlebar, the handlebar ends barely clear a few points during the fold. But I thought that I saw a make by cateye that looked promising. However, it isn't high priority at the moment.
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Old 01-10-09, 06:45 PM   #17
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What about this one? Anybody know the steerer tube (fork tube) dimension (1" or 1 1/8"?) on this one? https://sslrelay.com/s75353868.onean...NPOST2004%3D29
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Old 01-10-09, 08:07 PM   #18
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What are the inner diameters of the clamp the arrow is pointing to, on the 2008 and 2009 models respectively?
On the 2008 handlepost the QR clamp separates easily from the handlepost tube, so the inner diameter of the clamp is not important (it fits around the handlepost, as it should.) A 1" OD riser tube fits perfectly in the handlepost and clamps in tightly when the QR clamp is secured.

On the 2009 handlepost, the QR clamp is integrated in the handlepost, and the riser tube is non-removable. If I recall correctly, the diameter of the 2009 tube was more than 1".
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Old 01-10-09, 08:24 PM   #19
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You could take a hacksaw to the 1" riser to which the handlebar is welded, then clamp a 1" stem onto that, finally a nicer-looking flatbar. (I think a flatbar looks better than the riser.)
That's an option. I have embarrassingly few tools in my NYC apartment, but I do have a hacksaw. Given how cheap the required length of 6061T6 tube is, it seems a shame to cut up a perfectly OK handlebar.

I'm more concerned about the cost of the stem. I've found some insanely cheap stems but they are 120mm and longer. The Gaerlan stem that invisiblehand mentioned above is much more appropriate, only 50mm, but it's $24.95 + shipping. I'm holding out hope for a short extension, reasonably light stem for $10. Still looking.
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Old 01-11-09, 02:59 AM   #20
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You could take a hacksaw to the 1" riser to which the handlebar is welded, then clamp a 1" stem onto that, finally a nicer-looking flatbar.
Please don't use a hacksaw. Have a bike shop cut it with a steering tube cutter. If you must do it yourself, at least get a cheap pipe cutter from the hardware store.
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Old 01-11-09, 07:42 AM   #21
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Quote:
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On the 2008 handlepost the QR clamp separates easily from the handlepost tube, so the inner diameter of the clamp is not important (it fits around the handlepost, as it should.) A 1" OD riser tube fits perfectly in the handlepost and clamps in tightly when the QR clamp is secured.

On the 2009 handlepost, the QR clamp is integrated in the handlepost, and the riser tube is non-removable. If I recall correctly, the diameter of the 2009 tube was more than 1".
jur's earlier suggestion is the cleanest solution IMO: a 6061-T6 aluminum tube with a 25.4mm (one inch) outer diameter, that is long enough and whose wall is thick enough for the stresses it will receive, coupled with any standard stem that matches the outer diameters of both this makeshift riser tube and of the handlebars you want to use.

You'd just need to fashion a little cap to plug the hole at the top. You could probably use a cork from one of the olive-oil bottles sold at Trader Joes.

There are aircraft supply shops on eBay that sell tubing in custom lengths in various gauges if you cannot find this locally.
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Old 01-11-09, 08:45 AM   #22
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jur's earlier suggestion is the cleanest solution IMO: a 6061-T6 aluminum tube with a 25.4mm (one inch) outer diameter, that is long enough and whose wall is thick enough for the stresses it will receive, coupled with any standard stem that matches the outer diameters of both this makeshift riser tube and of the handlebars you want to use.There are aircraft supply shops on eBay that sell tubing in custom lengths in various gauges if you cannot find this locally.
Easy solution is to use a seatpost of the right size if you`we got one lying around or a bikeshop near by.



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You'd just need to fashion a little cap to plug the hole at the top. You could probably use a cork from one of the olive-oil bottles sold at Trader Joes.
Champagne cork! Or an eagle like the one Sheldon had on his helmet.
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Old 01-11-09, 09:17 AM   #23
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An eagle? Or the top of a Pickelhaube!
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Old 01-11-09, 10:23 AM   #24
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take the old strqaight up stem and than use a aber hallo stem
http://www.thorusa.com/dahon/accessories/handlebar.htm
to get extra reach ,, use a regular flat handlebar or even one with a little rise for even more adjusability

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Old 01-11-09, 02:23 PM   #25
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An eagle? Or the top of a Pickelhaube!
Well, that'd encourage me to be careful and avoid sudden stops! I think I'll go for the champagne cork, though.
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