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-   -   Why can't I fit this 25.4mm handlebar into a 25.4 stem? (https://www.bikeforums.net/showthread.php?t=1053702)

daveed 03-23-16 10:22 AM

Why can't I fit this 25.4mm handlebar into a 25.4 stem?
 
Must I resort to prying open my Kalloy Dirt Drop quill stem (25.4) to fit 25.4 Origin 8 road bar drops? Forcing the curvy bar through the stem seems like a bad idea. I'm not sure why the handlebar doesn't seem to fit. Anyone have a solution?

SquidPuppet 03-23-16 10:27 AM

Are you having difficulty getting the sharp bends of the bar through the stem clamp, or is it the clamping area of the bar that won't go into the stem?

aggiegrads 03-23-16 10:32 AM

I like to use a coin and the pinch bolt to slightly pry open clamps. This also works with seat post clamps.

Remove the pinch bolt, thread through the backside threads, and place a coin in the slot that the pinch bolt will hard stop against. Continuing to turn the bolt will slightly spread the clamp. Much preferable and safer than prying open with a flathead screwdriver.

This will not work if the tapped end is a blind hole or if the geometry of the stem does not allow you to start the pinch bolt through the threaded side.

Edit: looking at photos of the Kalloy dirt drop stem, it appears to be a blind hole.

daveed 03-23-16 10:53 AM

Yes, getting the sharp bends through the stem clamp. Thanks.

daveed 03-23-16 10:57 AM


Originally Posted by aggiegrads (Post 18630696)
I like to use a coin and the pinch bolt to slightly pry open clamps. This also works with seat post clamps.

Remove the pinch bolt, thread through the backside threads, and place a coin in the slot that the pinch bolt will hard stop against. Continuing to turn the bolt will slightly spread the clamp. Much preferable and safer than prying open with a flathead screwdriver.

This will not work if the tapped end is a blind hole or if the geometry of the stem does not allow you to start the pinch bolt through the threaded side.

Edit: looking at photos of the Kalloy dirt drop stem, it appears to be a blind hole.

Blind hole. Grrr!

fietsbob 03-23-16 10:59 AM

A well designed stem is less wide on the bolt side . the narrow part of the stem faces the radius center of the bends,

You probably have to remove the stem from the fork to get it to turn the proper way to have it sliding around the curves ..

fietsbob 03-23-16 11:01 AM

Oh and make sure its not a 26mm bar . drop bars in 1" centers have not been a thing for decades ..

Andrew R Stewart 03-23-16 11:29 AM

This thread is a VERY good example of why buying by the numbers only still can end up with problems. (And I'm not trying to pick on the OP, just using his issue as a learning point). On paper the stem and bars are compatible. But in real life the bars curves are such that they hang up on the stem's clamp width. The bars are made in the era of removable face plate stems where the bar shape is no issue to install. The stem was designed in an era of bars having large enough curves to pass through the stem's clamp width. These "dimensions" are never stated because either manufacturer didn't have the other's product in mind.

The solutions have already been stated. Try opening up the stem's clamp either with a bolt forced manor or a pry bar one. Grease up the bar's curves. Be willing to have some bar marring. In the end there is a point that a good mechanic will say the combo won't work. Knowing when to back away from the bench is a very good skill to have, too bad too few accept this option. Andy.

daveed 03-23-16 11:38 AM


Originally Posted by Andrew R Stewart (Post 18630860)
This thread is a VERY good example of why buying by the numbers only still can end up with problems. (And I'm not trying to pick on the OP, just using his issue as a learning point). On paper the stem and bars are compatible. But in real life the bars curves are such that they hang up on the stem's clamp width. The bars are made in the era of removable face plate stems where the bar shape is no issue to install. The stem was designed in an era of bars having large enough curves to pass through the stem's clamp width. These "dimensions" are never stated because either manufacturer didn't have the other's product in mind.

The solutions have already been stated. Try opening up the stem's clamp either with a bolt forced manor or a pry bar one. Grease up the bar's curves. Be willing to have some bar marring. In the end there is a point that a good mechanic will say the combo won't work. Knowing when to back away from the bench is a very good skill to have, too bad too few accept this option. Andy.

Heh-heh. Well-stated, sir. (I have another hair-brained project going, but will save it for a future post.)

CliffordK 03-23-16 01:25 PM

It seems as if I've often had to twist the bars a bit to find the "sweet spot" to get around the curves, although a perfect cylinder shouldn't need it.

Just make sure you figure out which way to start, and don't install the bars backwards :eek:

FBinNY 03-23-16 01:37 PM

You may NEVER get this to fit.

Stems made for drop bars are carefully designed with relieved areas which can clear the inside radius of a drop bar. It's sometimes a bit of a chinese puzzle to keep turning the bar so the inside of the curve is where the relief is, but that's how it's done.

OTOH stems made for BMX or upright bars which lack sharp inside curves don't need and often don't have this relief, so no curvy bar can ever be slid in.

CliffordK 03-23-16 01:41 PM

My Bike Friday just cuts the bars right down the middle.
It is EASY to install, even with brifters and tape already on the bars :thumb:

Ok, so the bars have an internal sleeve, and they have a special wide clamp, but...

LesterOfPuppets 03-23-16 01:52 PM

I'd probably just get a stem with removable faceplate.

Product Description | Origin8

Andy_K 03-23-16 03:08 PM


Originally Posted by Andrew R Stewart (Post 18630860)
Be willing to have some bar marring.


Originally Posted by FBinNY (Post 18631203)
It's sometimes a bit of a chinese puzzle to keep turning the bar so the inside of the curve is where the relief is, but that's how it's done.

This is my experience with quill stems and drop bars. Sometimes it seems like it won't pass, but then I turn the stem and bars in various ways and it slips through. I usually scratch the bars, but since I'm going to have bar tape over the scratched spots that doesn't bother me. I haven't run into a combination that just won't work, but I don't doubt that it happens.

I've got a Salsa Poco bar which is compact and has the weird zig zag bend on the drops. Those are always a challenge to get through any stem without a separate face plate, but so far I've managed it.

FBinNY 03-23-16 03:27 PM

For those dealing with classic single bolt road stems

Here's an old trick from BITD.

Remove the bolt, and thread it in from the opposite (threaded) side. Place a penny in the slot, and turn the bolt in until it makes contact. Then you can use the bolt to gently jack the stem open a millimeter or two and prevent scratching a bar as you install it. Just be careful to make sure the penny is not in the way, and don't jack the stem open beyond it's spring range, all you need is 1-2mm at most.


SquidPuppet 03-23-16 03:37 PM


Originally Posted by FBinNY (Post 18631456)
For those dealing with classic single bolt road stems

Here's an old trick from BITD.

Remove the bolt, and thread it in from the opposite (threaded) side. Place a penny in the slot, and turn the bolt in until it makes contact. Then you can use the bolt to gently jack the stem open a millimeter or two and prevent scratching a bar as you install it. Just be careful to make sure the penny is not in the way, and don't jack the stem open beyond it's spring range, all you need is 1-2mm at most.


What? Post number three wasn't good enough for you? :p

FBinNY 03-23-16 03:43 PM


Originally Posted by SquidPuppet (Post 18631484)
What? Post number three wasn't good enough for you? :p

I don't usually read EVERY post in a thread. I do a quick scan, and sometimes miss stuff and end up repeating prior posts. Compost happens.

SquidPuppet 03-23-16 03:45 PM


Originally Posted by FBinNY (Post 18631498)
I don't usually read EVERY post in a thread. I do a quick scan, and sometimes miss stuff and end up repeating prior posts. Compost happens.

:)

trailangel 03-23-16 05:06 PM

I don't think Origin8 makes 25.4mm road drop bars, just 26mm

CliffordK 03-24-16 01:50 AM


Originally Posted by SquidPuppet (Post 18631484)
What? Post number three wasn't good enough for you? :p

Not when considering post number 5.


Originally Posted by daveed (Post 18630763)
Blind hole. Grrr!


Bike tinker man 03-24-16 04:15 AM

From my humble experience:-

Some stems are slightly wider than others at the clamp area, & some drop bars have tighter bends in than others.

I find it best to take the stem off from the bike & feed the stem on the handlebar.

SquidPuppet 03-24-16 07:44 AM


Originally Posted by CliffordK (Post 18632381)
Not when considering post number 5.

And how was post 15 any different? That was my point.

daveed 03-24-16 08:44 AM


Originally Posted by trailangel (Post 18631688)
I don't think Origin8 makes 25.4mm road drop bars, just 26mm

Origin does, in fact. And, by the way, I twisted the handlebar through the hole once I found the sweet spot mentioned in another post. Thank you.
Origin8 - Pro Pulsion Alloy Gary-2 Handlebar, 530 x 25.4mm, Black

Manu431 09-06-19 07:37 AM

I have faced the same problem yesterday.
I had many difficulties to use my available 25.4mm stem (which was installed previously installed with a city handlebar 25.4mm) to fit on my new purchased 25.4mm drop bar.
It is very frustrating.

I finally managed with difficulties to get it thru the curve, but the bar is now full of scratching . Not really a problem because it will be covered with bartape, but I don't like the concept at all of scratching a brand new drop bar.

But it is not finished. Once the curve has been passed thru, the stem doesn't fit on the 25.4mm center part of the dropbar (24.5mm written on the handlebar). It should, but it doesn't fit.
it looks as the stem is just slightly to small, but i can not install it on the drop bar. I should open the stem a little, but I could not managed to find a solution to open it a little that at the moment. I should try again, or resigned and purchase a new front-opened stem.
my stem has no thread side. It use screw and nut, so I don't think that the trick with a coin could work.

Totally annoying.


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