Happy new year to all.

I am adjusting the top tube length on a couple of bikes by installing different stems. The bikes came with short stems. I have road style handlebars, and the older style stems that do not come apart. The reason these replacement stems are useful is that they are the right (longer) length and they fit into the steering tubes of the respective bikes. Also, of course, because they are here and now. I would rather keep these stems than to buy newer vintage. To get the bars into the stems, I need to somehow open up the jaw of the stem.

I tried wiggling the stem back and forth. But there is not enough opening in the jaws to do it smoothly, or even at all. I looked on Youtube for help. But the demos I found were all for the newer stems that break apart. Does anyone have any ideas?

Thanks in advance.

Saul

Are you using mountain bike stems with road bars?
Different diameters.

Just as a matter of jargon, you're not adjusting the top tube length, you are adjusting the reach. The bike's top tube can't be adjusted.

Are you talking about quill stems, like this? If so, you need to remove the handlebar tape and brake levers and thread the bar through the stem's bar clamp.

Watch this video. It will tell you everything you need to know about this
Bing Videos

As mentioned above make sure they are matching clamp/bar diameters. The key to getting the bars in the clamp is to rotate the bars (or stem is easier if it's not installed yet) as you try to get it around the bar bends. Should go through with some patience and finessing. Usually not necessary to pry open the clamp but sometimes needed but don't pry it too far open.

I always pry them open slightly with a flat screwdriver.

Get a threadless adapter for your bike or bikes and then changing stems and bars becomes easier. You don't even have to remove the bar tape, STI's or anything else on the bars when you decide to try a different stem length. Here is one just to show you what it is.

https://www.treefortbikes.com/Zoom-Q...rk-286mm-1-1-8

You can find them in all different finishes and colors if you look enough. Of course you'll have to buy the stem too. Notice this and most others go from the 1" quill size to let you use a standard 1 1/8" stem with whatever diameter your handlebars clamp area is.

On your current stem and bars, you have to turn the bars to find what will allow the bends to go through the stem. You might also have to pry the clamp on the bars open just a very little bit.

as somebody pointed out above, at least on Cinelli stems, the lower part of the stem (where the clamp bolt is) is narrower, and by rotating the bars you can find the way to slide the bars thru the stem such that the inner radius of the bar bends are oriented towards that narrower part of the stem.

Mismatched bar / stem combos may not be so user-friendly.

I am not a big fan of using "a big screwdriver" to spread the clamping piece of the stem. there is a technique using a bolt and a coin that is very controllable. Don't spread it any wider than necessary.

/markp

He's talking about length no reach, which quill stems certainly vary in as well as reach.
https://www.somafabshop.com/shop/nit...4109#attr=3773

Some stem clamps (of the single bolt design) are too wide for the bar's tight curves to fit through. This is why some stem clamps have their undersides next to the clamp's slot beveled back, to gain more clearance. Still many times the clamp needs to be pried open a touch while wiggling/snaking the bars through. The industry has made specific pry tools for this (Specialized as example) but with the advent of the split clamp two bolt designs are no longer needed or offered. Flat blade screwdrivers and the open end of a wrench sometimes also work but the chance of the pry tool slipping and/or marring the stem are greater.

I suggest that one make really sure the stem is being slid on the bars pointing in the correct direction before prying anything. Andy

I guess only the OP can clarify, which might be difficult because he is confused about terminology.

Yeah, of course quill stems can vary in terms of what you call "length" which I guess is the length of the insertion (aka height) and also the extension length. Other (more?) common ways of referring to these are "length" for the extension and "height" (not length) for how tall it is. Nitto makes some very tall stems, up to 225 of insertion length as well as a variety of extension lengths, e.g. 80, 90, 100, etc. mm.

Blah, blah, blah... But regardless.

He said

Since he referred to adjusting the "top tube length" and stems being "short", I thought he was obviously referring to adjusting the reach by adjusting the extension length of the stem. From your comment and link, I think you're thinking he's referring to the insertion length/height of the stems, not the extension length? I doubt that based on his original statement.

But I could be wrong in understanding both the OP and your comment. So, please excuse me if I am.

Again, only the OP knows what he's hoping to do and what he is talking about vis a vis the stem and "top tube length", I hope he clarifies and the posts have helped him get the bars into the new stem.

Interesting idea.

for getting drop bars through this type of stem usually requires some turning of the bars as you work your way through the curved parts of the bars.

I think opening the stem is what the OP is needing. And mpetry912 's method is a far better way than how I've always done it.

Yes, "reach" is the term that I forgot. And yes, too, it is a quill type stem. Also, the handlebars are the right size for the stem. Also also, they are road style handlebars. However, I looked at the video. And the place in the video where it looks like the stem slips off easily in the video is the place where it gets stuck for me. I *think* I remember that there was some way of wedging the stem open enough to run the handlebars through. The penny trick does not work because the threading is not part of the stem; it is a pinch bolt with a nut.

Thanks to all for your wise guidance. I think I'm going to take it to may all-time favorite mechanic who taught me most of what I know.

Saul

saul, you have to turn the bars when you get to the start of the curved parts. go slowly and trial and error it. Yes, prying the bit open a bit with a screwdriver helps, but its the turny turny in the right direction/position that is the trick.

I havent done it in years, but certainly recall wondering how the .... to do it the first time, and getting the bars jammed a bit, until I thought things through properly and figured it out as I went.

good luck, even if someone else shows you, it will be a skill to learn.
On one of my old bikes about 30 years ago, I could have done with a stem a bit shorter or taller, but just couldnt be bothered screwing around with removing the tape, the brakes and messing getting the bars out again, so just left it and lived with it.
Newer stems are so much easier!

Wouldn’t the nut as per the photo still hold it, if there’s enough of a gap to get one in there?

ISTR there was also a 26.2 mm bar/stem, 3TTT perhaps?

I find a cold chisel works well, just wiggle it gently into the gap. On steel stems you can be more forceful.

Pedantics for sure (what else is BF good for, right?), but I think the definition of a bike's reach is independent of stem length. I think most define it as the horizontal distance between the center of the crank to the top point of the head tube, where the steer tube exits through the upper headset bearing.


From: https://road.cc/content/feature/what...portant-266968

Using that definition, you can't change a bike's reach by changing the stem's length. Conversationally, though, I think we all know the intent here...to change the distance from the saddle to the end of the stem.

Is there a well-defined metric for that? Something like "effective reach"? Some sort of horizontal measurement from the end of the stem, where the bar mounts, rearward to where it'd intersect the seat post?

After reading your post, I was wondering what it's called when you lengthen or shorten the stem length. I did know that reach vis a vis frame geometry is as you describe. So I looked it up. (to add ammo to my pedantry stock )

I guess what it's called, and what I was talking about, and what the OP was trying to do -s to change "handlebar reach"? Oh well.

The correct word does not matter substantively. what I need is a longer distance between my tush and my hands on the bars. The bars I am using are all the proper thickness for the stems that I am talking about. And the stem thicknesses are all the same. So compatibility is not an issue.

Thanks for all the ideas.I think I am going to take the whole schmutz to "ye olde bike shoppe," the one that has been around since back in the day, where they have done this before. Most stuff I can do myself. But this project is vexing.

Saul

Nobody likes a quitter... lol.

Just joking, it sounds like you want a longer stem. The penny bolt and nut will work unless you can't fit the nut and coin between. Regardless it could also be that you need to change up your cables to accommodate the change in reach.

It sounds like you really want to do this yourself, which I support. I would investigate the local area for a co-op. One may have exactly what you are looking for in parts and experience.

Thanks to all for your thoughtful comments. I took the parts to a bike shop that I trust. And the mechanic pointed out that you need to have the open part of the stem on the inside of the bend of the bars. All the stems went on the new bars without incident. I feel like such a nimnul!

Anyway, the right sized stems are now on the bikes. And I have no excuse for not riding!

Saul

Saul, this is what I was trying to get across, that you needed to turn the bars, rotate the bars, to get them through the stern.
Well, now you understand!
We all went through this at one point and learned.