Handlebar conversion on the bicycle: Properly mount and adjust handlebars & stem

Why should you invest time in handlebar assembly? Quite simply – the bike's cockpit is literally the pivotal point between you and the bicycle, it has to work. Moreover, it is partly responsible for your seating position and thus for your comfort.

Here you will learn how to assemble a control center from handlebars and stem that provides optimal comfort and more performance.

Why is it worth converting the handlebars?

You have already read it – the handlebars and the stem determine how your upper body is positioned on the bicycle . They also influence the steering characteristics of the bicycle. 

→ So if you are not sitting comfortably on the bicycle and constantly struggle with numb hands, aching shoulders, or back problems, it is worth realigning the handlebars or replacing the handlebars and stem. 

→ Even if you feel that you do not have good control over your bike, a new handlebar or a different handlebar position can help.

“The cockpit” of the bicycle consists of a whole lot of individual parts that must work perfectly together for your bike to fit and function. These points are important:

• The handlebar is one of the three contact points between the bicycle and the rider and thus a crucial factor for comfort, steering precision, and safety. Handlebars come in different shapes and widths, which can greatly change your posture and steering characteristics.
• The stem is often not really noticed, for many it is simply a part of the handlebars. But it is actually an independent bicycle part, connecting the bike and the handlebars. Thus, it is responsible for you being comfortable, controlled, and safe on the road. The length of the stem influences how stretched you sit. The stem can also be straight or angled up or down, then the handlebars move higher or lower.
• Spacers are rings in different thicknesses that you can place under the stem to raise the cockpit overall. 
• Additionally, the shift and brake levers are part of the cockpit, as well as grips (or handlebar tape) and the headset are included. 

Here you see the combination of stem, handlebars, and spacers. Image © Bombtrack

To ensure optimal function, handlebars and stem must be properly mounted and adjusted. In this post, we provide you with valuable tips for handlebar assembly and adjusting your cockpit.

For handlebar assembly or changing the stem, a set of Allen keys and a torque wrench are usually sufficient.

The Right Tool for Handlebar Installation on a Bicycle

To properly install or adjust your bicycle handlebar along with the stem, you don't need any special tools. A well-equipped toolbox should contain everything necessary to change the handlebar:

• Important are Allen keys, preferably a whole set of them, so that the right size for the clamp screws of your stem and the ahead cap is certainly included.
• A torque wrench ensures the correct torque and guarantees that no components or screws are damaged.
• To align the brake/shift levers on a road bike or gravel bike at the same height, a measuring tape or ruler is needed.
• For carbon parts, a bicycle assembly paste is highly recommended.

Tools for Bicycle Handlebar Installation

Allen keys | Torque Wrench | Assembly Paste

When changing the handlebar of a gravel bike or road bike, there is more to consider than when changing an MTB handlebar.

Changing Bicycle Handlebar and Stem on Road Bike & Gravel Bike

The longer your gravel bike trips or road bike rides are, the more important it is to set up your cockpit comfortably. Here's how:

Changing the Stem

Changing the stem on your road bike or gravel bike is quite simple, you can easily try it yourself.

1. You first remove the handlebar at the four screws of the stem clamp, loosen the two screws on the side of the stem to the steerer tube, and unscrew the ahead cap. Now you should hold the fork if your road bike or gravel bike is not on the ground, as the fork might slip out otherwise.
2. Remove the spacers and the old stem and thread the new one onto the steerer tube. Make sure that the build height of the new stem matches the dimensions of the old model. If the new stem is lower in its build height, an additional spacer or shortening of the steerer tube may be necessary. If not, reattach the previously installed spacers and screw the ahead cap back into the steerer tube hand-tight.
3. Next install the bicycle handlebar with the four screws on the stem. Important: Pay attention to cross-tightening (first bottom left, then top right, then top left, then bottom right) and the correct torque . Next, use the Ahead screw to set the correct distance of the headset. To do this, pull the front brake and move your bike slightly back and forth. With your index finger on the lower headset, you can feel if there is still play between the fork and the headset. Minimal turns of the Ahead screw may be enough to fix the play. Never tighten the Ahead screw too much, as you might crush the headset.
4. Finally align the stem straight with the front wheel and use a torque wrench to tighten the two side screws as recommended by the manufacturer.

Clearly visible: the Ahead screw (see arrow) and the manufacturer's specifications for the torque to be applied.

Handlebar conversion on a road bike or gravel bike 

1. Before you can mount a new drop bar on the gravel bike or a road bike handlebar, you must remove the brifters and other accessories. To do this, flip up the rubber overlaps of the brake levers and loosen the locking screw (just loosen, do not unscrew).
2. Completely unwrap the handlebar tape and detach the brake and shift cables from the bicycle handlebar. These are usually fixed to the handlebar with electrical tape. Now pull the brake/shift levers down and carefully lay them aside. They are held by the cables on the bicycle.

The fixation of the brake/shift lever (=brifter) is done via the screw located under the grip rubber. You can simply flip it up.

3. Now you can loosen the four screws that fix the old bicycle handlebar to the stem and  remove the old handlebar. Place the new road bike handlebar centrally in the designated clamping area of the stem and screw it tight. Make sure not to fully tighten the four screws yet and first align the handlebar horizontally. Next, proceed with the final handlebar assembly, for which you thread the brake levers back onto the handlebar – do not swap the left with the right! You only need to roughly position them for now and then lightly tighten the locking screws of the brake levers. 
4. In the next step align the levers. For the height, you can use the markings on the handlebar, a spirit level, or a measuring tape; both should be mounted at exactly the same height on the handlebar bend. Also, consider the angle of the brake levers. They should be mounted parallel to the drop of the handlebar. For handlebars with flare (outward bend), for example, slightly turned outward. When correctly aligned, the brake lever covers the lower handlebar when you look at your bike from the front. 
5. Once you have set the appropriate positions, you can tighten the lever's locking screws and attach the cables to the road or gravel handlebars with electrical tape. For handlebars with internal cable routing, you must of course route the cables through the handlebars at this point. Only then do you wrap the new handlebar tape around both sides of the handlebars and finally fold back the rubber grips of the levers.

Changing the handlebars of an MTB flat bar is not difficult. However, you should work carefully, as great forces act on these handlebars! 

Handlebar Conversion & Stem Change on the MTB

Especially on the MTB, it is worth experimenting with different stems, handlebar widths, and shapes, as the riding characteristics can change significantly with just a few centimeters more or less.

Mounting the Stem on the Mountain Bike

1. Before you can change the stem of your MTB and mount a new one, you must first get rid of the old one. To do this, take a suitable Allen key and loosen the four screws on the clamp between the handlebar and stem.
2. Once you have unscrewed all four screws, you can remove the handlebar and carefully lay it forward. It is now still held by the brake and shift cables. 
3. Next, you loosen the two screws on the stem that are positioned sideways to the fork. About 1.5 turns are usually enough here. Now the large ahead screw is loosened. Warning – if your bike is hanging in the repair stand, you must hold your fork firmly when loosening the ahead screw, otherwise it will fall out. If your bike is on the ground, this naturally does not happen. Now loosen the ahead screw, remove the spacers (if present), and pull the stem upwards off the steerer tube.
4. For the handlebar installation you can follow the instructions in reverse order. Insert the new stem onto the steerer tube and place the ahead cap with screw from above in its place and tighten it slightly – caution… the large ahead screw is an adjustment screw, not a locking screw! Now attach the handlebar again and secure it with the four screws on the stem. Use a torque wrench for the final turns and always follow the manufacturer's specifications regarding the force applied, which you can find either on the stem or in the user manual. Always tighten the four screws in a cross pattern.
5. Next, you move your bike slowly back and forth with the front brake engaged . With your index finger, feel at the lower transition between the fork and frame to check if there is still any play. If nothing wobbles there anymore, you can also tighten the side stem screws. A torque wrench is also recommended here. However, make sure to align the handlebars straight beforehand. Stand centrally over your bike, look down at the (suspension) fork of your bike, and compare the visual distances between the handlebars and the fork. If the distance is the same on both sides, your handlebars are optimally aligned.
6. If the headset still has some play, simply tighten the Ahead screw a bit more. Usually, minimal rotational movements with the Allen key are sufficient.

When converting handlebars on a mountain bike, first loosen the grips, brake levers, and shift levers.

Handlebar installation of a new handlebar on a mountain bike

Installing a new handlebar on the MTB is usually quick and easy.

1. First, remove the grips and the brake and shift levers from the old handlebar. You can carefully lay down the brake and shift levers and let them hang on the cables or wrap them around the frame with cable ties or insulating tape.
2. In the next step loosen the four screws on the stem, remove the handlebar and attach the new one in reverse order. When tightening the four screws, you must again pay attention to the correct torque and tighten the screws alternately in a cross pattern evenly. Make sure that the gap dimensions of the handlebar clamp are the same at the top and bottom.
3. Finally, thread the shift & brake levers and the grips back onto the handlebar. Make sure not to swap the brake levers and mount them as you have previously used them. You can align the brake grips evenly with a spirit level, but usually, an optical check from the side of the handlebar is sufficient.

Especially in combination with carbon components (here the fork steerer), you should definitely use a torque wrench and adhere to the manufacturer's torque specifications.

The special features when installing carbon bicycle handlebars and stems

As always, caution is advised when installing carbon components. When mounting carbon handlebars and converting to a carbon stem, a few special rules apply when changing your components. 

Here you must absolutely pay attention to the correct torque . To tighten all screw connections correctly, you absolutely need a torque wrench In most cases, you will find a print on the carbon handlebar or carbon stem with the  allowed values in Newton meters (NM). If this is not the case, the user manual will certainly help you.

It is also advisable to use special bicycle assembly paste, in this case Carbon Paste , when assembling carbon parts such as road bike carbon handlebars and mountain bike carbon handlebars. 

↳Material & Information for Carbon Handlebar Assembly ↵

Torque Wrench | Carbon Assembly Paste | Info: Blog Torque Wrench | Info: Blog Carbon Paste

Note: Carbon Paste is not the same as lubricants or anti-corrosion greases. Carbon pastes do not reduce adhesion, they enhance it. If you want to know more, you can find all the important information about assembling carbon components in our article "What is Carbon Assembly Paste and why do you need it?"

Handlebar Change on the Bicycle – What's the Benefit?

Now you know how... but why should you make the effort and reach for the torque wrench? Clearly, if a bicycle part has aged or eventually gives up, you need a replacement. But even with a brand-new bicycle, many riders often reach for a handlebar conversion with the torque wrench after a short time.

• The stem determines how far you have to stretch to the handlebar. Short stem: upright seating, long stem: stretched seating position! 
• The stem can also have a more or less steep angle and thus influence the seating position. The upper body is raised higher or bent lower over the handlebar.
• All handlebars – whether for an MTB, road bike, gravel, city, or trekking bike – are available in different widths and shapes, which significantly change the ergonomics, the position of the arms, the riding stability, and the wind resistance.
• Handlebars can also have different diameters. Depending on the size of your hands, this can provide relief.
• There are also different materials that affect the weight and stiffness of the handlebar.

Read the blog post “Adjusting Bicycle Handlebars” for all the important information.