Drop bar conversion on a mtb
#1
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Drop bar conversion on a mtb
I picked up a 1992 Trek 950; the bike is sweet with lugs, true temper tubing, and Deore LX parts (except for the few bits that the PO changed out). The paint job is in really excellent shape. It also has a super long wheelbase and so I want to do a drop bar conversion and turn it into a road/offroad touring bike.
Here is my problem. The bike has a 1 and 1/8 inch threaded fork which limits my ability to find tall stems. The stem needs to be around 8 and 1/2 above the top tube. That's a lot. The top tube though is the right length for me and the saddle height is of course a non-issue.
I think I have two options:
(1) I own a one inch nitto dirt drop stem that would do the job height wise but of course it is the wrong size. I could look around for a shim but I'm a little leery of this. Probably no good reason but I'm really conservative--for pretty obvious reasons I think--when it comes to stems and handlebars. Anyone have any experience in shimming a one inch quill stem so it fits into a 1 and 1/8 inch fork? I haven't had a lot of luck finding a shim like this; perhaps someone here could point me in the right direction?
(2) Alternatively I could get a threaded to threadless converter like this nitto, https://www.benscycle.com/p-2509-nit...-286254mm.aspx. I really, really like nitto products and trust them. It's not very long though. I should be able to find a threadless stem that angles upward sharply.
Am I missing something here? Is there another solution that I should be thinking about? I'd like to get this right the first time.
Here is my problem. The bike has a 1 and 1/8 inch threaded fork which limits my ability to find tall stems. The stem needs to be around 8 and 1/2 above the top tube. That's a lot. The top tube though is the right length for me and the saddle height is of course a non-issue.
I think I have two options:
(1) I own a one inch nitto dirt drop stem that would do the job height wise but of course it is the wrong size. I could look around for a shim but I'm a little leery of this. Probably no good reason but I'm really conservative--for pretty obvious reasons I think--when it comes to stems and handlebars. Anyone have any experience in shimming a one inch quill stem so it fits into a 1 and 1/8 inch fork? I haven't had a lot of luck finding a shim like this; perhaps someone here could point me in the right direction?
(2) Alternatively I could get a threaded to threadless converter like this nitto, https://www.benscycle.com/p-2509-nit...-286254mm.aspx. I really, really like nitto products and trust them. It's not very long though. I should be able to find a threadless stem that angles upward sharply.
Am I missing something here? Is there another solution that I should be thinking about? I'd like to get this right the first time.
#2
Thrifty Bill

Joined: Jan 2008
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From: Mans of NC & SW UT Desert
Bikes: 86 Katakura Silk, 87 Prologue X2, 88 Cimarron LE, 1975 Sekai 4000 Professional, 73 Paramount, plus more
Go with the converter. Opens up the world of opportunities.
I rarely recommend converters, but this is one of those cases where it just works. Find a good LBS that lets you try out various stems.
I rarely recommend converters, but this is one of those cases where it just works. Find a good LBS that lets you try out various stems.
#3
Aspiring curmudgeon


Joined: Aug 2014
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From: Saint Louis
Bikes: Guerciotti, Serotta, Gaulzetti
There are really ugly MTB/hybrid quill stems available in that diameter with a lot of rise.
Nashbar ATB Comfort Quill Stem
Nashbar ATB Comfort Quill Stem
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#4
multimodal commuter
Joined: Nov 2006
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From: NJ, NYC, LI
Bikes: 1940s Fothergill, 1959 Allegro Special, 1963? Claud Butler Olympic Sprint, Lambert 'Clubman', 1974 Fuji "the Ace", 1976 Holdsworth 650b conversion rando bike, 1983 Trek 720 tourer, 1984 Counterpoint Opus II, 1993 Basso Gap, 2010 Downtube 8h, and...
I picked up a 1992 Trek 950; the bike is sweet with lugs, true temper tubing, and Deore LX parts (except for the few bits that the PO changed out). The paint job is in really excellent shape. It also has a super long wheelbase and so I want to do a drop bar conversion and turn it into a road/offroad touring bike.
Here is my problem. The bike has a 1 and 1/8 inch threaded fork which limits my ability to find tall stems. The stem needs to be around 8 and 1/2 above the top tube. That's a lot. The top tube though is the right length for me and the saddle height is of course a non-issue.
I think I have two options:
(1) I own a one inch nitto dirt drop stem that would do the job height wise but of course it is the wrong size. I could look around for a shim but I'm a little leery of this. Probably no good reason but I'm really conservative--for pretty obvious reasons I think--when it comes to stems and handlebars. Anyone have any experience in shimming a one inch quill stem so it fits into a 1 and 1/8 inch fork? I haven't had a lot of luck finding a shim like this; perhaps someone here could point me in the right direction?
(2) Alternatively I could get a threaded to threadless converter like this nitto, https://www.benscycle.com/p-2509-nit...-286254mm.aspx. I really, really like nitto products and trust them. It's not very long though. I should be able to find a threadless stem that angles upward sharply.
Am I missing something here? Is there another solution that I should be thinking about? I'd like to get this right the first time.
Here is my problem. The bike has a 1 and 1/8 inch threaded fork which limits my ability to find tall stems. The stem needs to be around 8 and 1/2 above the top tube. That's a lot. The top tube though is the right length for me and the saddle height is of course a non-issue.
I think I have two options:
(1) I own a one inch nitto dirt drop stem that would do the job height wise but of course it is the wrong size. I could look around for a shim but I'm a little leery of this. Probably no good reason but I'm really conservative--for pretty obvious reasons I think--when it comes to stems and handlebars. Anyone have any experience in shimming a one inch quill stem so it fits into a 1 and 1/8 inch fork? I haven't had a lot of luck finding a shim like this; perhaps someone here could point me in the right direction?
(2) Alternatively I could get a threaded to threadless converter like this nitto, https://www.benscycle.com/p-2509-nit...-286254mm.aspx. I really, really like nitto products and trust them. It's not very long though. I should be able to find a threadless stem that angles upward sharply.
Am I missing something here? Is there another solution that I should be thinking about? I'd like to get this right the first time.
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#5
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From: Cedar Rapids, IA
Bikes: 1997 Rivendell Road Standard 650b conversion (tourer), 1988 Schwinn Project KOM-10 (gravel/tour), 2013 Foundry Auger disc (CX/gravel), 2016 Cannondale Fat CAAD 2 (MTB/winter), 2011 Cannondale Flash 29er Lefty (trail MTB)
I can't think of how you would safely shim a 1" quill stem to fit 1 1/8". I've never seen such a device.
So, I think the second option is your best (and safest) bet, paired with a +40 degree stem.
I've always admired those trek 9x0 lugged frames, but it's good to know that they have a weird headset. I avoid Fishers from the same era because of their 1 1/4" threadless headsets.
1" threadless isn't bad because it can be shimmed up. I did that with a drop bar conversion of a Univega Alpina for my girlfriend.
So, I think the second option is your best (and safest) bet, paired with a +40 degree stem.
I've always admired those trek 9x0 lugged frames, but it's good to know that they have a weird headset. I avoid Fishers from the same era because of their 1 1/4" threadless headsets.
1" threadless isn't bad because it can be shimmed up. I did that with a drop bar conversion of a Univega Alpina for my girlfriend.
#6
#7
It is not really weird - it's exactly the same size as modern 1-1/8" threadless, just with the steerer cut too short to clamp a stem on. However, modern 1-1/8" headsets and replacement forks will drop right in if you ever need to upgrade.
Last edited by Wilfred Laurier; 09-02-15 at 09:22 AM.
#8
I AM AI
Joined: Aug 2013
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From: Tucson, AZ
Bikes: 2008 S-Works Roubaix SL, 1979 Raleigh Comp GS, 1978 Schwinn Volare
This may help, or may add to your pain, but not long ago I found two (yes, two) of these at the co-op. Snatched 'em up like they were made of gold:

Manufactured by Kalloy (if that's a manufacturer as opposed to an indication of potassium alloy construction). Beyond that all I can tell you is they exist, and they look like this:


By way of contrast, here's what the same Trek looked like when the drop conversion was done but I was still on my stem quest:

That's a threaded-to-threadless converter, plus a threadless rise extender, plus a threadless stem. It was somewhere between comedic and horrifying. 2/3 of that assembly are now in the BOC if it's headed your way (I may have just violated one of the crappy rules). Anyway, unless it's temporary I wouldn't recommend going that route. Ugly, clunky, and heavy.
EDIT: Yep. If you take the time to construct a long and only slightly informative post in response to some issue, complete with the taking/uploading of pictures, you can safely assume that someone around here will solve the problem in two minutes and forty keystrokes while you do it.
[MENTION=165276]brian3069[/MENTION]

Manufactured by Kalloy (if that's a manufacturer as opposed to an indication of potassium alloy construction). Beyond that all I can tell you is they exist, and they look like this:


By way of contrast, here's what the same Trek looked like when the drop conversion was done but I was still on my stem quest:

That's a threaded-to-threadless converter, plus a threadless rise extender, plus a threadless stem. It was somewhere between comedic and horrifying. 2/3 of that assembly are now in the BOC if it's headed your way (I may have just violated one of the crappy rules). Anyway, unless it's temporary I wouldn't recommend going that route. Ugly, clunky, and heavy.
EDIT: Yep. If you take the time to construct a long and only slightly informative post in response to some issue, complete with the taking/uploading of pictures, you can safely assume that someone around here will solve the problem in two minutes and forty keystrokes while you do it.
[MENTION=165276]brian3069[/MENTION]
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A race bike in any era is a highly personal choice that at its "best" balances the requirements of fit, weight, handling, durability and cost tempered by the willingness to toss it and oneself down the pavement at considerable speed. ~Bandera
A race bike in any era is a highly personal choice that at its "best" balances the requirements of fit, weight, handling, durability and cost tempered by the willingness to toss it and oneself down the pavement at considerable speed. ~Bandera
Last edited by Fahrenheit531; 09-02-15 at 09:47 AM.
#9
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From: Tixkokob, Yucatán, México
Bikes: 79 Trek 930, 80 Trek 414, 84 Schwinn Letour Luxe (coupled), 92 Schwinn Paramount PDG 5
FWIW, I used a piece of a steel can to shim a way too small quill stem into my 92 Paramount, and it worked just fine. I know there are few here who would approve. This situation always reminds me of 'Zen and the Art of Motorcycle Maintenance'.
#10
That was likely a 21.1 stem (JIS 1"?) and a 22.2 steerer tube (ISO 1"?) - a total of 1.1mm diameter difference, so a 0.55mm shim is needed. For 1" to 1-1/8" the difference is 25.4-22.2 = 3.2mm, or 1.6mm shim, which would be a goddamn thick can.
#11
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Bikes: 1940s Fothergill, 1959 Allegro Special, 1963? Claud Butler Olympic Sprint, Lambert 'Clubman', 1974 Fuji "the Ace", 1976 Holdsworth 650b conversion rando bike, 1983 Trek 720 tourer, 1984 Counterpoint Opus II, 1993 Basso Gap, 2010 Downtube 8h, and...
To safely shim a 7/8" quill to fit in a 1" steerer, I would make a two-piece shim, each a piece of 1/16" aluminum curved into a half cylinder. The sliding wedge of the stem should push them apart, separately from one another, making a secure fit.
In bending 1/16" aluminum into a curve, its actual thickness may change a bit, so will need to be cleaned up with a flat file before it'll fit perfectly.
In bending 1/16" aluminum into a curve, its actual thickness may change a bit, so will need to be cleaned up with a flat file before it'll fit perfectly.
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#12
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Joined: Aug 2013
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From: Puget Sound
I just posted about this and bought this same stem in the 1" size for a conversion of my own. I was really impressed with the quality of it. I second it and recommend it. Plus, bonus for me was that I was able to use loop bars because the two bolt mount allowed me to mount them.
#13
[QUOTE=Tim_Iowa;18131494]I can't think of how you would safely shim a 1" quill stem to fit 1 1/8". I've never seen such a device.
QUOTE]
I have put them on a couple of bikes, including my daughter's. They work great. I didn't have any trouble finding them online.
QUOTE]
I have put them on a couple of bikes, including my daughter's. They work great. I didn't have any trouble finding them online.
#14
[QUOTE=Wilfred Laurier;18131534
It is not really weird - it's exactly the same size as modern 1-1/8" threadless, just with the steerer cut too short to clamp a stem on. However, modern 1-1/8" headsets and replacement forks will drop right in if you ever need to upgrade.[/QUOTE]
+1, I tend to prefer 1-1/8" vintage MTB frames and you can buy modern replacements from Surly, SOma or whatever if you pick up an old MTB with a suspension fork and 1-1/8" headtube... then you have modern, light and strong threadless set-up and can put a whack of spacers on it and it will look just like any other LHT out there.
It is not really weird - it's exactly the same size as modern 1-1/8" threadless, just with the steerer cut too short to clamp a stem on. However, modern 1-1/8" headsets and replacement forks will drop right in if you ever need to upgrade.[/QUOTE]
+1, I tend to prefer 1-1/8" vintage MTB frames and you can buy modern replacements from Surly, SOma or whatever if you pick up an old MTB with a suspension fork and 1-1/8" headtube... then you have modern, light and strong threadless set-up and can put a whack of spacers on it and it will look just like any other LHT out there.
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1 Super Record bike, 1 Nuovo Record bike, 1 Pista, 1 Road, 1 Cyclocross/Allrounder, 1 MTB, 1 Touring, 1 Fixed gear
1 Super Record bike, 1 Nuovo Record bike, 1 Pista, 1 Road, 1 Cyclocross/Allrounder, 1 MTB, 1 Touring, 1 Fixed gear
#15
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From: Cedar Rapids, IA
Bikes: 1997 Rivendell Road Standard 650b conversion (tourer), 1988 Schwinn Project KOM-10 (gravel/tour), 2013 Foundry Auger disc (CX/gravel), 2016 Cannondale Fat CAAD 2 (MTB/winter), 2011 Cannondale Flash 29er Lefty (trail MTB)
[QUOTE=Grand Bois;18131780]link?
#16
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I don't know if a nested quote will notify the nested poster or not. [MENTION=27118]Grand Bois[/MENTION]
#18
[QUOTE=Tim_Iowa;18131977]Okay, I'll find one for you. The ones I used are stainless steel, rolled over and not split at the top.
Alloy Shim to Fit 1 Inch 22.2 mm Insert Quill Stem - £13.27
Alloy Shim to Fit 1 Inch 22.2 mm Insert Quill Stem - £13.27
#19
Senior Member

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From: Tixkokob, Yucatán, México
Bikes: 79 Trek 930, 80 Trek 414, 84 Schwinn Letour Luxe (coupled), 92 Schwinn Paramount PDG 5
It was a much smaller stem. It came off a '74 Free Spirit, whose seatpost size was 20mm IIRC. The point I was trying to make is that there are options, outside the box, which can function just fine.
#20
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From: CID
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I'd go for the Kalloy/Sunlite/whatever 1-1/8" quill stems posted. They're a little ugly, but not quite as ugly as the adjustable ones. And the price is right.






