TheFort

Hey all,

I need an extreme adjustable stem due to back pain and a small torso/long legs. My question is how does a stem like this one work? It seems to have a bolt built in. Does that somehow produce compression? I'm currently using a compression plug in my carbon steerer. Just wondering how I get compression with one designed like this. Thanks!

https://cyclingdealusa.com/products/...40371176177829

veganbikes

So it sounds like you need a fitter. Go see one and then they can help you figure out your ideal riding position for the issues you are having. Go in be honest about what is going on and they can make you a whole lot more comfortable and figure out better solutions to your issues.

TheFort

No no no. Been to a fitter. My inseam is 35" and my torso is small (I'm 5"9 to give an idea). I need an adjustable stem because I want to be in an upright touring position.

So back to my question: how does this stem actually work, like specifically how do you get compression without a compression plug in the steerer?

gene99

so, it sounds like you need a suspension stem, or, depending on the type of bike you have, a suspension fork, to ease bumps.
for the stem, something like this:
https://redshiftsports.com/products/...BoCZYYQAvD_BwE

flan48

Hi Fort,
Have you considered a stem riser? These will definitely put you in a more upright position. Here is an example:
https://www.amazon.com/Delta-Cycle-B...544687058&th=1

Good luck and
Best regards

TheFort

The maker of the bike told me it's not safe to use a riser with a carbon steerer.

TheFort

This isn't meant to be offensive, but can anyone answer the actual question of how these are installed on a bike that uses a compression plug? Much appreciated!

veganbikes

Have you actually been to a fitter and explained your issues? It sounds like you kind of brushed that off as if you were just trying to avoid it. If you have seen a fitter and mentioned everything going on and what you are looking to achieve and they couldn't get you there I would be surprised or you found someone who may not be a fitter.

I would go see a fitter and again tell them your issues and what you are looking to get out of it which would be in your initial conversation at the start of the fit or maybe even before that. Fits are for everyone not just for people racing and that myth really needs to die and die quickly. Anyone who rides a bike or is looking to ride a bike more than once in a blue moon should get a fit, you will be more comfortable on your bike and be in a better position optimized for you not for racer x or something. A good dynamic fit will change your riding and up your comfort quite a bit.

You do have to be honest with your fitter though. They are not there to judge you they are there to help you but cannot help if you don't tell them what you need them to know. They can certainly figure out some stuff and probably a lot of stuff you didn't know or realize but in the end you can become quite comfortable. I know I did and know a lot of other folks who have benefitted as well.

njkayaker

The thing you linked to is a riser with a stem stuck on top.

Both types of risers don't use compression plugs given there's no access to the screw.

TheFort

Oh okay, I'm new to all this as you can probably tell. Lol. So this can't be used on a carbon steerer that has a compression plug?

So is the option to use the thing I linked completely out, or is there a mod where it can be used?

Thank you!

njkayaker

They provide no access to the plug.

​​​​​​The standard riser has a sticky-up part you clamp an separate stem to.

The riser you linked to has an integrated stem in place of the sticky-up part.

With respect to the steerer tube interface, they are exactly the same.

TheFort

Awesome, thanks. Mostly understand now.

But I still don't understand how does either create compression to hold the bearings together?

Like do I keep the compression plug in there and the thing I linked goes over that? ...But that can't work because it has a bolt in it...

freeranger

Don't know about using with a carbon steerer, but this one could be used with a compression plug. Maybe check with your LBS, or Ritchie on whether it should be used with a carbon steerer. Ritchey 4-Axis Adjustable Stem | Stems (ritcheylogic.com)

TheFort

Thanks. that one is only 55 degrees, and I need the 90 degree. Appreciate it, though.
I keep running into a limit on the degrees with the ones that have the donut hole cut out; that's why I was wondering about these other ones.

freeranger

? A 90 degree angle would be straight up. Here is an example of a 55 degree angle: drawing of 55 degree angle - Search (bing.com) 90 degrees seems drastic.

pdlamb

It looks like a standard threadless stem at the interface. You put a cap on the top, put "enough" spacers under the stem, and adjust the bolt through the cap. When you have the headset right, then you tighten the stem's bolts. You've got a separate bolt to let the rest of the stem rotate; when you get the bars where you want them, you'll tighten that adjustment bolt and probably rotate the bars to where they need to be.

Frankly, the stem you link to doesn't look like it's going to give you very much adjustment; it's likely too short to raise the bars much. But that's another question (that several of the posters here have jumped to).

njkayaker

The Satori ST-UP3 has an access hole at the top for the compression bolt.

Here's the video showing how it works:


This guy is using the standard type with a long bolt (or is the bolt people already have long enough?).


I think the concern with carbon steerer tubes the extra torque due to the increased length.

TheFort

But how does it compress the bearings? That's the part I'm confused about...

Does the compression plug go in the steerer tub as normally, and this thing goes over it?

TheFort

I asked the maker of the stem about the compression issue, and they said, "You need a star nut in the steering tube"

Does anyone know what this means? I know what a star nut is, but I don't know what they mean. Are they saying you replace the hex nut on the compression plug with a star nut? I guess I can ask, but they don't seem to want to help.

pdlamb

Take a look at Stem Removal & Installation: Threadless | Park Tool

njkayaker

They are just confused by your question. And they end-up telling you what you already know.

No, it works like a really long stem. (The risers can't fit over the cap.)

It works like the stem you already have (though, I'm not sure about how long the bolt needs to be).

The video shows clearly how it works.

Chandne

They work really well. I have a friend who has been cycling for over 20 years. Dirt biking messed him up due to crashes...mainly back issues and a hip issue. The last 6-7 years (after two bike fits) he has been using an adjustable step on his Dean Ti bike. He is a good rider and pretty fast. He can bomb the downhills too, and has had zero issues with it.

I am not sure about compression since the steer tube has the expander plug. It works like a regular stem.

TheFort

Thanks. Glad they work well. I'd love to try one!

But this is the thing nobody seems able to explain or understand.

Chandne

Maybe compression isn't a thing in these stems or any stem. The compression is inside the steer tube.

TheFort

But these stems have a built-in bolt in them that would bump into the compression plug in the steerer tube. That's the issue, unless I'm missing something.