How to Replace Handlebars

Replacing the handlebars on your bicycle is a common upgrade or repair that can improve comfort, control, and fit.

Difficulty: Intermediate
Tool level: Standard
Time needed: 30-45 min

Overview

Replacing the handlebars on your bicycle is a common upgrade or repair that can improve comfort, control, and fit. Whether you are swapping to a different bend, width, or rise, the process involves removing the old handlebar and installing a new one, then transferring over your controls and accessories. This guide covers the general steps for most conventional bicycles with threadless stems and standard clamp diameters. The exact procedure may vary slightly depending on your bike's design, so always consult the manufacturer's instructions for your specific components.

Before you begin, understand that handlebars are a critical safety component. Improper installation can lead to loss of control while riding. Work slowly and methodically, and if any step feels beyond your confidence, stop and visit a qualified bike shop. You will need basic mechanical skills and a set of standard tools. The job typically takes 30 to 45 minutes, but allow extra time if you are also replacing grips, tape, or cables. Having a clean, well-lit workspace and a way to hold the bike steady will make the process easier.

This guide assumes you are replacing the handlebar only, not the stem or headset. However, if you are changing handlebar style significantly, you may need new cables or housing. Always check that the new handlebar is compatible with your stem's clamp diameter and your controls' mounting diameter. When in doubt, ask a professional.

Signs it needs attention

Handlebars can last a long time, but they are not indestructible. Knowing when to replace them is key to safe riding. One clear sign is visible damage: cracks, deep scratches, or dents, especially near the stem clamp area or where controls mount. Even a small crack can propagate and cause sudden failure. Another sign is bending or deformation after a crash or impact. If the handlebar no longer aligns symmetrically with the stem or the bike's centerline, it may be compromised. Corrosion is also a concern, particularly on steel handlebars ridden in wet or salty conditions. Flaking chrome or rust streaks are warning signs.

Beyond physical damage, consider changes in your riding position or comfort. If you experience persistent numbness, wrist pain, or shoulder strain, a different handlebar shape or width might help. However, discomfort can also stem from bike fit issues, so consult a professional before assuming the handlebar is the culprit. Finally, if you are upgrading to a different style—such as from flat to riser, or from drop to alt—you will need to replace the handlebar to achieve the desired fit and control.

Regular inspection is wise. Once a year, or after any crash, remove the controls and inspect the clamp area. If you find any of these signs, replace the handlebar. Do not attempt to bend a handlebar back into shape; aluminum and carbon fiber can weaken and fail without warning.

Tools and parts you'll need

To replace your handlebars, gather the right tools and parts before you start. You will need a set of hex wrenches (also called Allen keys) in the sizes used on your bike—commonly 4mm, 5mm, and 6mm, but check your components. A torque wrench is highly recommended to tighten bolts to the manufacturer's recommended torque. Using the correct torque prevents crushing carbon bars or leaving bolts too loose. You may also need a screwdriver for some control clamps, and possibly a pair of cable cutters if you need to shorten cables or housing. A clean rag and some isopropyl alcohol are useful for cleaning surfaces.

For parts, you will need the new handlebar, which must match your stem's clamp diameter and your controls' mounting diameter. If you are switching to a different handlebar style, you may need new cables and housing, and possibly new grips or handlebar tape. If your old grips or tape are worn, it is a good time to replace them. Also, have some assembly grease or carbon fiber assembly paste on hand if your handlebar or stem requires it. Never use grease on carbon fiber unless the manufacturer explicitly allows it; use carbon paste instead.

A bike stand or a way to stabilize the bike is helpful but not mandatory. A bucket or a friend can hold the bike steady. Finally, have a container for small parts like bolts and spacers so they don't get lost. If you are unsure about any tool or part compatibility, consult your local bike shop.

Step-by-step

Start by securing the bike in a stand or stable position. If you have hydraulic brakes or internally routed cables, take extra care; you may need to disconnect them, which can require bleeding brakes later. For most mechanical setups, begin by loosening the stem's faceplate bolts evenly, a little at a time, until you can remove the faceplate. Keep the bolts and faceplate in a safe place. Then slide the handlebar out of the stem. If it is a drop bar, you may need to rotate it to clear the stem. Once the old handlebar is free, set it aside.

Next, transfer your controls and accessories to the new handlebar. This includes brake levers, shifters, grips or tape, and any bells or computers. If you are reusing cables, you may need to loosen the cable anchor bolts to remove the controls. Note the routing of cables and housing so you can replicate it on the new bar. Clean the new handlebar's clamp area with isopropyl alcohol to remove any grease or residue. Apply carbon assembly paste if the bar is carbon fiber and the manufacturer recommends it. Mount the controls loosely, then position the new handlebar in the stem. Center it and set the rotation to your preference. Tighten the stem faceplate bolts gradually and evenly in a cross pattern, using a torque wrench to the manufacturer's recommended torque.

Finally, adjust the controls to a comfortable position. For flat bars, set brake lever angle and shifter position. For drop bars, set the lever hoods and tape the bars if needed. Check that all cables operate smoothly and that the handlebar is secure. Take a short, cautious test ride in a safe area to ensure everything feels right. Re-tighten if necessary.

Common mistakes to avoid

One of the most common mistakes is over-tightening the stem bolts. This can crush carbon handlebars or deform aluminum ones, leading to failure. Always use a torque wrench and follow the manufacturer's recommended torque. Another mistake is uneven tightening of the faceplate bolts. Tighten them in a cross pattern, a quarter turn at a time, to ensure even clamping force. Also, do not forget to check the handlebar's clamp diameter matches the stem. Forcing a bar that is too large or using a shim incorrectly can be dangerous.

Another error is neglecting cable routing. If you route cables incorrectly, they may rub the frame, interfere with steering, or cause poor shifting and braking. Take a photo before disassembly to help with reassembly. Also, avoid reusing old cables and housing if they are frayed or corroded; new cables ensure reliable performance. When installing grips or tape, make sure they are secure and do not slip, especially in wet conditions. For drop bars, wrapping tape correctly takes practice; a loose wrap can unravel and cause loss of control.

Finally, do not skip the test ride. After installation, check that the handlebar does not rotate unexpectedly when you apply force. Stand over the bike and push down on the bars to simulate riding forces. If anything feels loose or creaks, investigate. If you are unsure, have a professional inspect your work.

When to visit a bike shop

While replacing handlebars is a manageable DIY task for many riders, some situations call for professional help. If your bike has hydraulic brakes with internally routed hoses, disconnecting and reconnecting them often requires bleeding the brakes, which is best left to a shop. Similarly, if your bike has electronic shifting with internal wiring, the complexity increases. If you are unsure about compatibility of your new handlebar with your stem, controls, or cables, a shop can advise you and may have parts on hand.

If you encounter a seized stem bolt, a corroded handlebar that won't budge, or a carbon fiber component that requires specific assembly paste and torque, consider visiting a shop. Also, if you have any doubt about your ability to install the handlebar safely, do not risk it. A handlebar failure can cause a serious crash. A professional can also help with bike fit if you are changing handlebar shape to address comfort issues.

Finally, if you notice any cracking or creaking after installation, or if the handlebar slips during a test ride, stop riding and seek professional inspection. Many shops offer quick checks and can confirm your work is safe. Remember, your safety is paramount; when in doubt, ask a qualified mechanic.

Frequently asked questions

Q: Can I reuse my old grips or handlebar tape when installing a new handlebar? A: It depends on their condition. If the grips or tape are in good shape and can be removed without damage, you can reuse them. However, grips often tear during removal, and tape loses its adhesive. It is usually best to install new grips or tape for safety and comfort. If you are unsure, replace them.

Q: How do I know if my new handlebar is compatible with my stem? A: Check the clamp diameter of both the handlebar and the stem. Common sizes include 25.4mm, 31.8mm, and 35mm. They must match exactly. Also, ensure the handlebar's control area diameter matches your brake levers and shifters. If you are unsure, consult the manufacturer's specifications or ask a bike shop.

Q: Do I need to adjust my brake and shift cables after replacing the handlebar? A: Often, yes. Even if you reuse the same cables, the new handlebar may have different routing or width, which can affect cable tension. After installation, test your brakes and shifting. If they feel off, adjust the cable tension or have a shop tune them. If you installed new cables, fine-tuning is almost always necessary.