A common complaint among customers is that "I'm leaning over too much on my bike." This is often the result of buying a bike that is too small for you, or buying the wrong style of bike for your needs (e.g. getting a road bike when you should have bought a hybrid bike). In other cases, you may need to make adjustments to your riding position while you're recovering from an injury to your back or neck.
Getting your position more upright on your bicycle can be accomplished by raising your handlebars. This can be an easy process on some bikes, or it can be somewhat involved on others. There are different systems used to attach the handlebar to the bike. Some of these systems have different levels of adjustability built into them. Other systems involve replacing parts to change the height of your handlebars.
The key component in any case is the stem, which is the part that clamps the handlebar on one end, and is inserted into or clamped onto the bike frame at the other end.
Quill stems are the type found on most vintage bikes, as well as some modern entry-level hybrid and mountain bikes, and most kids' bikes. This system can usually be identified by the two large nuts at the top of the head tube of the bike's frame.
Sometimes these nuts are hidden by a cone-shaped cover; this cover is cosmetic only.
Note that these nuts do not actually hold the stem in place. The bike's fork has threads at the top of the steerer tube; these nuts are screwed onto these threads and are used to adjust the amount of tension on the headset, which is the set of bearings that allow your steering to operate. Because of these threads, quill stems are sometimes referred to as "threaded" stems, although the term "threaded" technically applies to the steerer tube and the headset, not the stem.
The quill stem is actually held in place by a wedge bolt that fits inside the steerer tube. The quill stem is adjusted using the single bolt facing up on the top of the stem. This bolt usually has a 6 millimeter allen head.
To adjust the height of your quill stem, just loosen the top bolt by turning it counter-clockwise. This should allow the stem to rotate and move up and down freely. If the bolt is loose but the stem doesn't move, it may be seized up inside the steerer tube due to dirt and corrosion. If you hold the front wheel of the bike between your knees and turn the handlebars firmly, this should break the stickiness. Or, try tapping the top of the stem with a rubber mallet.
At this point, you can raise the position of your stem. Hold it in place as you re-tighten the top bolt, making sure that the neck of the stem is in line with your front tire.
IMPORTANT: Be sure that you do not raise the stem beyond the "maximum insertion point" line that is stamped onto the shaft of the stem. Doing so can cause damage to your bicycle, and potentially serious bodily injury.
If the length of your quill stem and the maximum insertion point does not allow you to get the handlebar high enough to your satisfaction, you can replace the stem. You can find a quill stem with a longer neck or one that has an adjustable angle, or both.
The key to choosing a new stem is selecting one that is the correct size for your bike. The two measurements that are important are the steerer tube size and the handlebar clamp size.
The steerer tube is most likely either 1 inch or 1-1/8 inches. The steerer tube is measured on the outside diameter, but where it can get confusing is that the stem is sized to fit the inside of the steerer tube. Thus, a quill stem for a 1-1/8 inch steerer tube actually measures 1 inch (25.4mm) in diameter. A quill stem for a 1 inch steerer tube actually measures 7/8 inch (22.2mm) in diameter.
Handlebar clamp sizes will either be 25.4mm or 26.0mm. Most mountain and hybrid bikes use the 25.4mm clamp, and most road bikes use 26.0mm. Some modern mountain and road bikes use a 31.8mm handlebar clamp, but these likely won't have quill stems.
Replacement quill stems start at around $27, with $10 in labor for installation.
Instead of a new stem, you can also purchase a quill stem extender. This is basically a tube of metal that inserts into your steerer tube, and then your original stem inserts into the top of the extender. These run about $20.
Threadless stems are found on most modern mountain and road bikes, and some mid-level and higher-end hybrid bikes. The term "threadless" technically refers to the absense of threading on the steerer tube and headset, and thus the absense of the two large nuts on the headset. A threadless stem clamps onto the outside of the steerer tube, and is held in place by one or two bolts situated horizontally at the back end of the stem.
There are usually a few spacer rings installed beneath and/or above the stem. You can adjust the height of the stem by swapping spacers from above to below, and vice-versa. If there are no spacers above the stem, then there is no way to move the stem any higher.
You have a couple of options for raising your stem and handlebars in this situation. First, you can install a steerer tube extender. This clamps to the top of your steerer tube, and then your stem clamps to the top of the extender. This can give you 2 to 4 inches of additional height. A threadless steerer tube extender runs about $40, with about $10 in labor for installation.
You can also choose to purchase a replacement stem with a different length and angle that gets you into your desired riding position. Threadless stems are also available with adjustable angles. Replacement stems start at about $35, with about $10 in labor for installation.
Choosing the proper size of your stem is similar to choosing a quill stem; you need the correct size for your steerer tube (usually 1 inch or 1-1/8 inch), and handlebar clamp size (25.4mm, 26.0mm, or 31.8mm).
Replacing a threadless stem should only be done by an experience bike mechanic, because to replace the stem, you must also remove and re-install the stem top cap. The stem top cap controls the tension on the headset bearings, and if this is not adjusted correctly, could lead to shorter life or damage to your headset.
Cables and housing
Regardless of whether you have a quill stem or threadless stem, the biggest issue you might run into when trying to raise your handlebars is having enough slack in your brake and shifter cables. Usually, bikes are assembled at the factory with enough slack for the stock stem height only, with very little room for upward adjustment. Often we find that to get the stem and handlebar high enough, we also need to replace some or all of the brake and shifter cables and housing. This job runs about $50 for parts and labor.
In conclusion, depending on the type of stem and handlebar system you have, in the best-case scenario, raising your handlebars is a quick, free adjustment, but in the worst-case scenario, it can be a job costing upwards of $100.
This article was published on November 6, 2012. Prices quoted are subject to change.