Bicycle Mechanics - stem adjustment

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jsmil4901
09-05-07, 07:54 AM
Can anyone give me some pointers on adjusting the stem on my specialized roubaix. I would like to change the angle downward. thanks.


tellyho
09-05-07, 08:15 AM
Not sure what type of stem you have, but I'm assuming threadless. Without buying a new stem, you have two options (possibly).

1. Pull the handlebars out of the faceplate, pull the stem and flip it over. Reinstall bars.

2. Move spacers that may be below the stem to above the stem (not generally an approved configuration, but functional).

HillRider
09-05-07, 08:34 AM
I'll assume this is a threadless set-up. If the stem is angled up you can reverse it by removing the bars, loosening the steerer clamp bolts and flipping it over. You can also remove spacers under the stem and place them on top to try the lower position. If it's what you want, the steerer can be cut shorter but be sure first.


jsmil4901
09-05-07, 03:35 PM
Thank you for the replies. I will try and flip the stem to see if that works. It is a new 2006 so I think I can flip it.

jimmythefly
09-05-07, 05:01 PM
I believe these came with Specialized's own stem and shim system. Look at the rear of the stem when mounted on your bike -is there a little +10 or -8 or something like that? This stem comes with a shim that fits between the stem and steerer tube of yoru fork. This shim has a built in angled spacer on the bottom of it (and also uses a top cap with an off-center bolt hole).

So, you may not have to remove the handlebars to lower them a small bit, it that's all you want.
1. remove top cap.
2. loosen the two stem bolts at the rear (the ones that clamp the steerer)
3. pull stem and shim off.
4. Rotate shim so thin part is toward the front of the bike.
5. Reinstall.
6. Learn how to adjust headset bearings.

Note that even if you undo the handlebars so you can flip the whole stem, the shim should always be on the underside. Effectively this system gives you two positive rise and two negative rise positions, and you can get other shims for even more options. Moving around spacers gives even more options.

If this sounds confusing, I'd just take it to a specialized dealer and have them show you, or perhaps look on their website.

jsmil4901
09-05-07, 05:10 PM
Thanks, that's exactly what I have. I will try and adjust it tonight.

Portis
09-05-07, 06:01 PM
Thanks, that's exactly what I have. I will try and adjust it tonight.

Keep in mind that you are not "adjusting" anything. You are removing the stem and turning it upside down. Also keep in mind that you are messing with a very important part of your bike in terms of safety. A stem coming loose at speed spells disaster.

Make sure you know the proper procedure before you start.