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T-shaped Handlepost Upper: No Such Thing?

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T-shaped Handlepost Upper: No Such Thing?

Old 08-24-21, 02:25 PM
  #1  
sjanzeir
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T-shaped Handlepost Upper: No Such Thing?

So, if you wanted to install one of those adjustable double stems from Syntace, you've got to replace the entire handlepost with a T-shaped one; you cannot simply just replace the factory upper with a T-shaped upper because no one makes an aftermarket T-shaped upper. Does this sound about right, or am I missing something here?
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Old 08-25-21, 02:27 AM
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Fentuz
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Are you talking about the telescopic Dahon stem clamp/handle post that goes up on a down?
https://foldingbike.biz/epages/7665e...dlepost_Uppers

I swapped the handle post on my helios and I find it much stabler than the telescopic version. The T version is monobock ~ 60 + 40 for the syntace kit.
I did it on the jetstream too however, the jetsteam handle post is monoblock but it has a top handle bar clamp (like the telescopic version. I used a litepro tube (25.4mm from memory) in the post clamp and the syntace braces joint the tube to the handlebar...

you could do the same. or alternatively, get a cheap aluminium straight flat bar, put it on your handle post, fit the syntace braces and cut to size... then, add you handle bar the the syntace brace and pop 4 end-caps to finish it off nicely
https://www.decathlon.co.uk/p/flat-h...523372-2635386
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Old 08-25-21, 08:33 AM
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Many of those dual-stem things come with a short bar/tube for which to clamp,
which effectively transforms the handlepost into the T-shape.
Some brands that make them are Litepro and ParasolTree.
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Old 08-26-21, 06:28 AM
  #4  
sjanzeir
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Originally Posted by Fentuz View Post
Are you talking about the telescopic Dahon stem clamp/handle post that goes up on a down?
I swapped the handle post on my helios and I find it much stabler than the telescopic version. The T version is monobock ~ 60 + 40 for the syntace kit.
Yes, that's the one that I have on both folders (albeit the one on the Mu has the nicer, wider clamps.) I do see where you're coming from with the monobloc handlepost being nicer and stiffer than the telescopic one. My problem, though, is that the handlepost tucks in between the two halves of the frame when the bike is folded; the bike won't fold completely (the magnet won't catch the coin) unless the handlepost is fully extended (both red dots are visible.) Here's what the situation looks like with the upper fully retracted:






As you can see, it's impossible to fold the bike fully with the upper in any position other than fully extended. So, if I install a monobloc handlepost of the same height as when the upper is fully retracted (which I prefer,) I won't be able to fold the bike securely.



Originally Posted by Nyah View Post
Many of those dual-stem things come with a short bar/tube for which to clamp,
which effectively transforms the handlepost into the T-shape.
Some brands that make them are Litepro and ParasolTree.
I realized that as soon as I looked at the Litepro stems. Now that my Litepro zero-offset seatpost is on the way, I can put myself a little farther forward along the wheelbase and bring the Hemingway a little closer to replicating the Mu's neutral handling. That Litepro stem will help, too. Thanks everyone!
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Old 08-26-21, 08:54 AM
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As you can see, it's impossible to fold the bike fully with the upper in any position other than fully extended. So, if I install a monobloc handlepost of the same height as when the upper is fully retracted (which I prefer,) I won't be able to fold the bike securely.
Try folding it with the handlepost across the frame instead of in-between it (pull the seatpost entirely out of the seat-tube before folding the handlepost). Here's what mine looks like fully folded and the seatpost put back in:

Last edited by Nyah; 08-26-21 at 08:58 AM.
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Old 09-25-21, 10:58 AM
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tomtomtom123
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With the tern Andros adapter, you can quickly rotate the handle to the vertical position when folding. But you still need a T post. The Andros has something like double the offset/length. I use it on my dahon to bring the reach further rearward. I have a seatpost with a 2cm rear offset but the brooks saddle is much further forward than most seats and I still need another 1 to 2cm rear offset to get it in the optimal position.
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Old 09-25-21, 12:23 PM
  #7  
sjanzeir
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Originally Posted by tomtomtom123 View Post
With the tern Andros adapter, you can quickly rotate the handle to the vertical position when folding. But you still need a T post. The Andros has something like double the offset/length. I use it on my dahon to bring the reach further rearward. I have a seatpost with a 2cm rear offset but the brooks saddle is much further forward than most seats and I still need another 1 to 2cm rear offset to get it in the optimal position.
A zero-offset Litepro solved that particular problem for me.

When I first got my Hemingway late last year,
I was kind of disappointed with the way it handled, especially compared to my Mu D9's neutral, tossable nature. Whereas you could pretty much point the Mu where you want it to go and just go for it, throwing it into almost any corner at any speed, the Hemingway's front end felt fluffy and light, which isn't at all what I would call confidence-inspiring.

Even when I clamped it down all the way forward, with the rails pushed right against the seatpost bracket, the tip of the Hemingway's saddle was still about 18mm or so farther back from the handlebars than where it was on my current Mu D9 (both the Hemingway and the Mu have identical saddles; I even swapped them over to make sure that what I was seeing was accurate.)

So I started taking measurements of both frames - the Mu and the Hemingway. As it turns out, both frames are more or less identical in all but two parameters: head tube length and effective seat tube angle. At 100mm, the Mu's headtube was 15mm taller than the Hemingway's 85mm headtube. Correspondingly, that put the Mu's handlebars 15mm higher off of the front axle than the Hemingway's - which I found somewhat surprising given the Mu's more "roady" nature, as opposed to the somewhat more "MTB-ish" Hemingway.

Obviously, the Hemingway's slacker effective seat tube angle (by about one degree, as measured with a protractor app on the seatposts of both bikes, parked over the same two floor tiles, with both tires on the ground,) was responsible for the saddle being set back farther than it is on the Mu.

So, in order to get the Hemingway to handle as sweetly as the Mu, I needed a way to get my ass (and, thus, my body mass) a little closer to the middle of the wheelbase, similar to where it would be on the Mu, effectively steepening the seat tube angle.

To achieve this, I had to swap out the factory 20mm-offset seatpost for a zero-offset one, which apparently only Litepro sold. After set the saddle in where I wanted it and clamped everything down, I went for a ride, and wow! It was as though I had just bought me a new Hemingway! The bike's ride, handling, and overall fun factor were orders of magnitude better than they were the day I took it home. It's still not exactly like the Mu (nor did I expect the experience to be replicated, what with the different tires and all,) but the change made the difference between a bike I didn't want to ride anymore (and which I had up for sale for a while,) and one I now look forward to hopping onto every day.
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