I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
Also, I don't have the packaging for it anymore and I'm not sure what the clamp diameter is on it. The bars I have are 26.0 (Italian) and it seems to clamp down well enough to where it doesn't seem to rotate, but I don't know how I can measure the clamp.
-alan
-- Alan Hoyle - [email hidden] - http://www.alanhoyle.com/ "I don't want the world, I just want your half." -TMBG Get Horizontal, Play Ultimate.
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
Also, I don't have the packaging for it anymore and I'm not sure what the clamp diameter is on it. The bars I have are 26.0 (Italian) and it seems to clamp down well enough to where it doesn't seem to rotate, but I don't know how I can measure the clamp.
-alan
-- Alan Hoyle - [email hidden] - http://www.alanhoyle.com/ "I don't want the world, I just want your half." -TMBG Get Horizontal, Play Ultimate.
I have one of those stems that used to be on a hybrid I have, I don't know the torque spec, but I had the same problem, mine seemed to loosen over time and I just torqued the heck out of it. I think you would really have to gorilla it to damage it.
[...] the stem seems to be "loose" at the adjustment joint.
[...] I just torqued the heck out of it. I think you would really have to gorilla it to damage it.
Wow, I could not disagree more, if this is the same kind of adjustable Zoom quill stem I bought about eight months ago.
This was the type where you tighten a bolt to draw a triangular, ridged aluminum block up against a ribbed section of the moveable part of the stem to lock it in place.
I was using a standard Allen key, just holding the stem in my hands (it wasn't clamped to a stand or anything). I was just playing with it, and voop, the threads on the aluminum wedge vanished.
Maybe I got the crappy kind, and there's a good kind, though. The experience definitely soured me on "adjustable" anything, though.
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
I've only used the threadless version of this stem. I heavily greased every mating surface of the clamp parts to make sure there would be no creaking and no binding when the bolt was tightened down. I had no problems for the few months of service I put it to use.
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
Quoted message said:
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
I've only used the threadless version of this stem. I heavily greased every mating surface of the clamp parts to make sure there would be no creaking and no binding when the bolt was tightened down. I had no problems for the few months of service I put it to use.
The loose one I saw (think it was Zoom, but not sure) used plastic teeth in the gearing. The plastic teeth were partially stripped. If I were U, I'd disassemble it to inspect exactly what the problem is. If it is worn plastic gear teeth, I wouldn't ride it. Although I don't know how catastrophically they may or may not fail. It may be possible to order only the plastic gear for replacement.
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
All adjustable stems do this, they're [censored]. You're much better of (and safer!) to get the measurements from the adjustable stem then purchasing an standard stem in that shape.
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
Also, I don't have the packaging for it anymore and I'm not sure what the clamp diameter is on it. The bars I have are 26.0 (Italian) and it seems to clamp down well enough to where it doesn't seem to rotate, but I don't know how I can measure the clamp.
-alan
-- Alan Hoyle - [email hidden] - http://www.alanhoyle.com/ "I don't want the world, I just want your half." -TMBG Get Horizontal, Play Ultimate.
Hello,
I have a Jamis Coda with an adjustable stem and I had the same problem last year.I can't remember which, but I either pulled up or pushed down on the stem as I tightened the adjuster bolt, and the stem was solid after that. Just a week ago I adjusted the bike and had the same problem, totally forgetting what had worked the last time. I played around for a bit, and "rediscovered" that trick. Since it worked twice I don't think it was just a fluke, but it seems odd that pulling up or pushing down would help.
My stem looks kinda like this one: http://nordicgroup.us/bikerec/images/stem2.gif ; on mine the bolt on the side loosens to adjust, and tightens to lock into that position. I'm not familiar with other styles of adjustable stems, so I don't know if they adjust via a similar mechanism or not.
[...] the stem seems to be "loose" at the adjustment joint.
Quoted message said:
Just A User said:
[...] I just torqued the heck out of it. I think you would really have to gorilla it to damage it.
Quoted message said:
Wow, I could not disagree more, if this is the same kind of adjustable Zoom quill stem I bought about eight months ago.
This was the type where you tighten a bolt to draw a triangular, ridged aluminum block up against a ribbed section of the moveable part of the stem to lock it in place.
I was using a standard Allen key, just holding the stem in my hands (it wasn't clamped to a stand or anything). I was just playing with it, and voop, the threads on the aluminum wedge vanished.
Maybe I got the crappy kind, and there's a good kind, though. The experience definitely soured me on "adjustable" anything, though.
These are not cold forged Italian equipment but they have been supplied to the millions of pieces per year an new bikes for quite a while and failure rates are low.
The wedge doesn't have threads. Did something fail? Just wondering. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
All adjustable stems do this, they're [censored]. You're much better of (and safer!) to get the measurements from the adjustable stem then purchasing an standard stem in that shape.
FWIW, I've sold bikes with Ritchey and even Kalloy without a single complaint. They certainly add an element of adjustability to a bike that doesn't exist otherwise, and are a valid way to determine the "right stem" even if you plan on replacing it with a lighter "fixed stem" later on.
On Wed, 11 Apr 2007 18:09:28 -0500, A Muzi <[email hidden]>
Quoted message said:
Quoted message said:
Wow, I could not disagree more, if this is the same kind of adjustable Zoom quill stem I bought about eight months ago.
This was the type where you tighten a bolt to draw a triangular, ridged aluminum block up against a ribbed section of the moveable part of the stem to lock it in place.
I was using a standard Allen key, just holding the stem in my hands (it wasn't clamped to a stand or anything). I was just playing with it, and voop, the threads on the aluminum wedge vanished.
These are not cold forged Italian equipment but they have been supplied to the millions of pieces per year an new bikes for quite a while and failure rates are low.
The wedge doesn't have threads. Did something fail? Just wondering.
If it's the same problem I had, the aluminum threads in the stem body stripped. Took me a couple years to break it, and to be honest, I wonder if it was my fault for not tightening the bolts on either side of the bars evenly. (The Nitto I replaced it with is lovely, though!)
I have a Zoom adjustable threaded stem that I'm trying to use on a 80's road/fixed gear conversion. I've got two problems with it: one real and one potential.
The demonstrable problem is that the stem seems to be "loose" at the adjustment joint. If I pull up to climb, the whole thing seems to pop up a fraction of an inch. Is there some trick to tightening these down? I can't find documentation online for torque specs.
All adjustable stems do this, they're [censored]. You're much better of (and safer!) to get the measurements from the adjustable stem then purchasing an standard stem in that shape.
Quoted message said:
FWIW, I've sold bikes with Ritchey and even Kalloy without a single complaint. They certainly add an element of adjustability to a bike that doesn't exist otherwise, and are a valid way to determine the "right stem" even if you plan on replacing it with a lighter "fixed stem" later on.
This is what I'm going to do. It turns out that the model stem I have is indeed a 25.4mm clamp, but the handlebars are 26.0mm diameter. It seems like it fits, but I don't think it's a good idea to keep this setup.
Now I just need to decide if I'm going to get a regular threaded stem or get a threaded to threadless adapter, move the stem from my road bike, and "upgrade" that stem. Clearly the cheaper way would be the former, but I have wanted to get a stem 1-2 cm longer for the road bike...
Thanks for the advice all.
-alan
-- Alan Hoyle - [email hidden] - http://www.alanhoyle.com/ "I don't want the world, I just want your half." -TMBG Get Horizontal, Play Ultimate.
On Wed, 11 Apr 2007 18:09:28 -0500, A Muzi <[email hidden]>
Quoted message said:
The wedge doesn't have threads. Did something fail? Just wondering.
If it's the same problem I had, the aluminum threads in the stem body stripped.
I went out to my garage this morning to have a look, but I'm pretty sure I threw it out. I'm sure you're right; I can envision the bolt passing through the wedge and threading into the stem.
So, it must have been the threads in the stem that stripped. I was even thinking to myself, "I should be careful". I'm not Mozart with a wrench or anything, but I've never stripped anything that easy before that wasn't made of cheese. Maybe I got a bum part.
On Wed, 11 Apr 2007 18:09:28 -0500, A Muzi <[email hidden]>
Quoted message said:
The wedge doesn't have threads. Did something fail? Just wondering.
If it's the same problem I had, the aluminum threads in the stem body stripped.
I went out to my garage this morning to have a look, but I'm pretty sure I threw it out. I'm sure you're right; I can envision the bolt passing through the wedge and threading into the stem.
So, it must have been the threads in the stem that stripped. I was even thinking to myself, "I should be careful". I'm not Mozart with a wrench or anything, but I've never stripped anything that easy before that wasn't made of cheese. Maybe I got a bum part.
Not necessarily. Mine had a bit of slop around the bar, so you could (and I probably did) screw it tight on one side, getting full engagement of the bolt on that side, and then get only about half that much engagement on the other side of the bar. With a bit of time, that slowly stripped the threads, and when I readjusted, there was only the other half of the threads left to hold it, which then stripped a bit faster.
Looking back, I suspect things would have been fine if Kalloy (or me) had used bolts that were about 1/4" to 1/2" longer. But that would have added 2 cents to the cost of the stem, and it wouldn't have been quite so neat looking with bolts sticking out the bottom.
