Bicycle Mechanics - stem size for Trek mtn bike

hello I am sitting here at work and wish to order a steering stem extender online.(bares are to low for mw) Have read pretty much about it (on this forum and like from Sheldon Brown) and from what I've read I could almost guess I need a one inch size, which seems to be most standard.
Does anyone happen to know what size steerer stem a Trek 850 Antelope (like mid - late 80's) would use?
Am just asking on the off chance someone can give me that info, so I can order now, before going home and trying to figure it out.
Thanks!
Em

The 850 Antelope originally used a quill-type stem, which isn't compatible with the stem extenders I think you're considering. If you've already adjusted the stem as high as it will safely go, you'll need a whole new one with a longer quill to go higher.

hi Juicemouse, thanks for your response,
this is what I was wanting to order:
http://harriscyclery.net/site/itemdetails.cfm?ID=1884&Catalog=39&sort=Price
they (at Harris) emailed me back saying I need to go ahead and measure as they were not sure about the Trek. So, I guess the ordering will have to wait.
:)

hi Juicemouse, thanks for your response,
this is what I was wanting to order:
http://harriscyclery.net/site/itemdetails.cfm?ID=1884&Catalog=39&sort=Price
they (at Harris) emailed me back saying I need to go ahead and measure as they were not sure about the Trek. So, I guess the ordering will have to wait.
:)


Ah ha! I've never seen such a device! Brilliant! Your bike almost certainly uses the 1" size.

ok, thx. Will report back if it is otherwise.
I appreciate the input.
:)

hi Juicemouse, thanks for your response,
this is what I was wanting to order:
http://harriscyclery.net/site/itemdetails.cfm?ID=1884&Catalog=39&sort=Price


If/when you get the extender, I would appreciate a review... I am looking to raise the bars on my old Cannondale touring bike.

One of my curiosities is how the extender's wedge is tightened... My guess is that it must require a long allen wrench reaching inside the upper portion.

good question. Maybe an excuse to buy a long t-handle allen in that size. Or! a set!
will let you know if I do get this, or, Tom, at Harris Cyclery, answered my email very promptly, maybe you could drop him a line.
Order@HarrisCyclery.net
:)

Not sure about your bike, but my '89 Trek 970 has a 1 1/8" threaded steerer.

Not sure about your bike, but my '89 Trek 970 has a 1 1/8" threaded steerer.

I'd double check that year. Trek didn't switch to 1 1/8" head tubes until 1991, while they continued to make lugged steel 9xx MTB frames up to 1993. 1994 was the fist year for TIG welded 9xx series frames.

I'm actually not sure what year my bike is.
Today when I got home I loosened the Allen bolt in the stem to see if I could just pull it up some in the steering head and re-tighten it but higher.
The thing that (at the moment) prevents that from happening, is, the front brake cable. On this Trek the cable loops into a hole on the top surface of the hollow stem and emerges from the other side as naked cable. Goes in with plastic sheath, comes up just cable. So the plastic sheath is stopping the stem from being able to be pulled up any higher. If I force it, it engages the front brake.
So I guess what needs to happen is disconnect that cable, pull it out of the hole in the stem and cut back the plastic sheath a bit, to expose more of the cable itself, to allow the stem to be position higher up. I think the cable itself is long enough for an inch or 2 up, but that plastic sheath, now, stopping that from being possible.
On my OTHER Trek, a very funky white 800, that cable doesn't go through the stem, but rather goes through a little brace (a "stay"?) with a hole in it big enough for the cable but not the cable housing or sheathing.
Anyway, that cable is going to have to be altered, whether I get the stem extender or even just decide to raise my stem a bit. Right now it only protrudes up maybe an inch over the top of the top ring at the top of the steering head.
Sorry folks I really AM going to learn some bicycle specific terminology, but in the interim, I hope I made myself understandible.
:)
Em

The size of the stem is usually stamped on the quill. You can disconnect the front brake QR, pull the stem out, wipe any grease off and look carefully. If you see a number like 22.2, your headset is 1". Likewise, if it reads 25.4, your headset is 1 1/8"

Be sure to add grease before inserting the stem and mind the minimum insertion mark.

so the headset is a bit bigger than the quill size? Is that to allow for the quill to be forced outward a bit as its tightened?
and thank you, for the tip about the grease.
Em

A 1" steerer tube (measured by the outside diameter) will accept a 7/8" (22.2mm) quill stem.

A 1 1/8" steerer will accept a 1" (25.4mm) quill stem.

I'd double check that year. Trek didn't switch to 1 1/8" head tubes until 1991, while they continued to make lugged steel 9xx MTB frames up to 1993. 1994 was the fist year for TIG welded 9xx series frames.

OK. I'm just going by what the seller told me. There are a few numbers under the bottom bracket. The largest is 933155. Is that the serial number?

OK. I'm just going by what the seller told me. There are a few numbers under the bottom bracket. The largest is 933155. Is that the serial number?

I'm not going by the serial number, just my memory. I worked for several Trek dealers from 1989 to 2000.

I owned a 1989 Trek 950 and one of my coworkers had the same model year 970. Both had 1" head tubes and ran the derailleur cables under the BB. The 1990 9xx models were similar.

If your lugged frame has a 1-1/8" head tube and all cables are routed along the top tube, it's a 1991 thru 1993 model.

If your lugged frame has a 1-1/8" head tube and all cables are routed along the top tube, it's a 1991 thru 1993 model.

That's what it is. Well how about that? Imagine, an inaccurate description on eBay! Oh well, no harm. It's a good frame nonetheless.

If/when you get the extender, I would appreciate a review... I am looking to raise the bars on my old Cannondale touring bike.

One of my curiosities is how the extender's wedge is tightened... My guess is that it must require a long allen wrench reaching inside the upper portion.

There is one for the threadless and threaded styles. I recently raised my riding position for both and went with a Delta. And yes, the one for a threadless has a long bolt to fit the star nut. The one for threadless has a conventional wedge and uses a newer style threadless type stem.

1 1/8 inch steerer tubes didn't start until the mid or late 90's I believe (might be wrong???).

1 1/8 inch steerer tubes didn't start until the mid or late 90's I believe (might be wrong???).

They were introduced in the late '80s to confront Gary Fisher's 'Evolution' headset size -1 1/4". By 1990 there were a few production bikes with 1 1/8" headsets, dubbed OS for 'oversize'. In 1991 most of the major manufacturers had switched to OS, with small builders like Ritchey, Bontrager and Salsa holding out for 1" with the attitude OS was heavy and unneeded. They eventually came around, which is why there were several MTB frames made in the early '90s with 1" head tubes.