Bicycle Mechanics - stem swapping

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peripatetic
02-24-05, 07:22 AM
If I have an older road bike (1980's), and I want to put on a longer stem, can this be done with a newer style headset, or do I have to change the fork also? Are headsets/steerers that accomodate older quill-style stems NOT compatible with the newer style of stems? Anyone know any good sites WITH diagrams that can explain this? I need to visualize it all better, and I really don't want to take the headset apart without having something to do with it once I have.


sydney
02-24-05, 07:39 AM
If I have an older road bike (1980's), and I want to put on a longer stem, can this be done with a newer style headset, or do I have to change the fork also? Are headsets/steerers that accomodate older quill-style stems NOT compatible with the newer style of stems? Anyone know any good sites WITH diagrams that can explain this? I need to visualize it all better, and I really don't want to take the headset apart without having something to do with it once I have.With a threaded HS, you don't have to mess with it to change stems. Simply loosen the center bolt in the stem quill and hope things aren't frozen up.If you want to use a threadless stem, you first replace your stem with a quill adapter which again requires no messsing with the HS. You mentioned 'newer style HS', which implies thredless. If you want a threadless headset, then you need a threadless fork and stem too.

peripatetic
02-24-05, 07:48 AM
Alright, this is what I was wondering about. There's such a thing as a quill adapter. Do those cost a lot? Where can you get 'em? Online, or LBS?

thanks for the quick answer sydney!


sydney
02-24-05, 07:51 AM
Alright, this is what I was wondering about. There's such a thing as a quill adapter. Do those cost a lot? Where can you get 'em? Online, or LBS?

thanks for the quick answer sydney!They cost about $20 or less. performance or nashbar has em. One downside is that they don't have as long a quill as some threaded stems,so that could be an issue if you need to get the bars higher. But the stems that can be used with them also can be had with alot of positive rise.

Grasschopper
02-24-05, 07:53 AM
http://www.nashbar.com/profile.cfm?category=119&subcategory=1185&brand=&sku=9755&storetype=&estoreid=&pagename= Not overly expensive. LBS may have them as well they are a fairly common accessory.

cyccommute
02-24-05, 07:55 AM
Alright, this is what I was wondering about. There's such a thing as a quill adapter. Do those cost a lot? Where can you get 'em? Online, or LBS?

thanks for the quick answer sydney!

Nashbar carries them here (http://www.nashbar.com/profile.cfm?category=119&subcategory=1185&brand=&sku=9755&storetype=&estoreid=&pagename=).

Stuart Black

Diggy18
02-24-05, 11:33 AM
There's also that stem adapter you can throw on top of that quill adapter, and that will let you mount the stem much higher.

peripatetic
02-24-05, 11:44 AM
...adapters on adapters...

Actually, 'm ONLY looking for length here--I have a disproportionately long torso, and the bike frame just doesn't give me enough upper body stretch. But I'm glad to know the info.

One last thing to anyone--what's the standard take on quality for the adapters and stems, too. Does it really matter all that much whether u pay 20 bucks vs. 50 or 60? What's important in terms of quality--materials or manufacturing techniques? And for either, what's the general hierarchy of quality measurements for materials/techniques?

Michel Gagnon
02-24-05, 06:42 PM
But why to you want a quill adaptor ?

You could get a traditional stem that has a longer quill. Rivendell offers a very nice Nitto Tecnomic (sp) stem, but there is also the less-delicate-but-cheaper-and-easier-to-find Zoom adjustable stem (I have two of them).

DieselDan
02-24-05, 06:51 PM
There's also that stem adapter you can throw on top of that quill adapter, and that will let you mount the stem much higher.

Then there are quill stem extenders.....

sydney
02-24-05, 09:25 PM
Then there are quill stem extenders.....Really??

bikejack
02-24-05, 09:36 PM
130mm is about maximum old or new (I'm sure someone will post a dealer with 140's) after that it's bigger frame time.

supcom
02-24-05, 09:58 PM
Do you want your stem up higher from the ground or further from the saddle?

Nitto Technomic is 225 mm tall, with up to 130 mm extension if you have 26.0mm bars. 120mm for 25.4mm bars. Many other shorter extensions available.

http://aebike.com/site/page.cfm?PageID=30&SKU=SM1421

peripatetic
02-24-05, 10:19 PM
Do you want your stem up higher from the ground or further from the saddle?

Nitto Technomic is 225 mm tall, with up to 130 mm extension if you have 26.0mm bars. 120mm for 25.4mm bars. Many other shorter extensions available.

http://aebike.com/site/page.cfm?PageID=30&SKU=SM1421

I've looked at Rivendell. Cost, people, cost. Don't have lots of dough to throw around at this--Rivendell is quite nice quality, but you pay for it.

And I think I stated it before, I'm just looking for extension--about 120-125mm. My wrists are aching, and when I stretch out, my butt scoots off of the back of the saddle. I've ridden it enough to know that the reach is just too short. I don't feel like I need any height on it--I like the control I've got riding lower.

By the way, can anyone describe the difference in handling when you move the handlebars further over the wheel axle? I'm kind of going with something I read about Greg Lemond's recommendation that when you look down at the wheel, the axle should be hidden behind the handlebars. This sounds right to me: currently, I can see the axle, and the handlebars just seem too far back. (There was also a recommendation on ???? web page that sore wrists tell you to increase your stem length.)

Michel Gagnon
02-25-05, 12:09 AM
As I said, the Zoom is not as beautiful, but still quite decent... and much cheaper. I paid mine about $25 CDN each.
If you can't find it at your local store, look at
[http://harriscyclery.net/site/page.cfm?PageID=49&Description=&Brand=485&Submit.x=17&Submit.y=11]this item[/url] (link from Sheldon Brown's site)

P.S. I roughly measured one bicycle:
- quill : 120 mm of quill exposed ; I could extend safely it a further 30-40 mm.
- stem : an upwards angle of 10-35 degrees looks best; mine is at 20 degrees up, so the bars are 150 mm above the headset crown.

As for sore wrists vs stem length, I don't remember the page, but it could have been a suggetion regarding a specific bicycle/rider combo. The more standard variables are handlebar tilt (i.e. rotation in the stem bracket) and orientation of the "bar ends". But as always, if bars are too far away, too low -- or too close or too high, it plays a role.

sydney
02-25-05, 07:00 AM
I've looked at Rivendell. Cost, people, cost. Don't have lots of dough to throw around at this--Rivendell is quite nice quality, but you pay for it.

And I think I stated it before, I'm just looking for extension--about 120-125mm. Just get a quill stem with a longer extension. Plenty of inexpensive ones out there. Make sure the calmp diameter matches your bar.

DieselDan
02-25-05, 06:48 PM
Really??
Really really

sydney
02-25-05, 06:52 PM
Really reallyShow me.

peripatetic
02-26-05, 02:47 AM
As for sore wrists vs stem length, I don't remember the page, but it could have been a suggetion regarding a specific bicycle/rider combo. The more standard variables are handlebar tilt (i.e. rotation in the stem bracket) and orientation of the "bar ends". But as always, if bars are too far away, too low -- or too close or too high, it plays a role.


This is what I read, by Jim Langley. A quick fix solution to a common 'bike fit problem:'

http://www.jimlangley.net/crank/bikefitchart.html

His solution definitely seems most likely for me.
(It's easy to tell, once you're looking for it, that your torso is disproportionately long for your legs--the seat height is right, but I'm either cramped on the saddle with hands in the drops, or scooting off of the back of the seat in order to stretch out more.)

Any input onto how moving the handlebars further over the front wheel axle will affect handling? I assume that the more vertical you can get your hands over the axle, the better your control. (Just my own hypothesis, based on limited empirical evidence.)