One of the key things we do to make our test bikes handle better is adjusting handlebar height. Often, the off-the-shelf bar height doesn’t lend itself to optimal handling. With that in mind, here’s our guide on how to adjust handlebar height.
Riders will often experiment with saddle height, tyre pressure, bar angle and suspension settings, but few are aware of the benefits of adjusting bar height. Bar height is also known as saddle-drop which is the measurement of how far the top of the saddle sits above (or below) the bars.
Elite riders normally have a significant drop, where their bars sit below the saddle, whereas recreational riders usually don’t.
Generally speaking, a lower handlebar height reduces your centre of gravity. By placing more weight over the front wheel, you increase traction. Additionally a lower bar height provides a more centred position between both wheels to improve bike control, especially during climbing. These traits are even more noticeable off-road, especially with 29ers.
There is a limit; going too low can make the bike difficult to control. Luckily, experimenting with bar height is easy and most often free. The guide below applies to modern threadless style stems and headsets. If your stem has bolts pinching it onto the steerer tube, it’s most likely threadless.
Time: 15 minutes
Skill rating: Easy
Tools you’ll need
A multi-tool or a set of Allen keys
A torque wrench or pre-set Torq key is recommended, especially if working with carbon or lighter parts
Some stems, such as those from Zipp, Ritchey and Syncros, will use Torx keys rather than Allen bolts and so a T20 or T25 Torx key will be required
Use those spacers
The first and easiest way to adjust handlebar height is by moving headset spacers.
This bike features four headset spacers. The piece below the fourth spacer is the headset bearing cover and should not be removedOli Woodman/Immediate Media
The headset spacers sit on the fork’s steerer tube and help preload the headset bearings during adjustment. Generally, most bikes have 20 to 30mm of headset spacers that can be moved freely above or below the stem. All bolts in the stem are standard threaded (ie ‘lefty-loosey, and righty-tighty’).
1. Start with the bike’s wheels firmly on the ground and then loosen the clamp bolts on the back of the stem. This is a good time to add a little fresh grease to the top cap bolt which can easily become seized in place.
Loosen each of these bolts, a little at a time, one after the other until you feel no resistanceOli Woodman/Immediate Media
2. Remove the top cap that sits on top of the stem.
The top cap bolt will most often require a 4mm or 5mm allen keyOli Woodman/Immediate Media
3. Slide the stem off the steerer tube.
If it is difficult to remove the stem, loosen the clamp bolts furtherOli Woodman/Immediate Media
This is what the top cap and bolt look like when undone. These pieces thread into an item called a star nut.
On carbon bikes there is usually an expanding wedge in place of a star nut. You don’t need to remove this.Oli Woodman/Immediate Media
4. Decide how much you’d like to lower or raise your bar and add or remove the appropriately sized spacer(s).
Even a small change to the height of your handlebars can make a big difference so don’t be afraid to play with this arrangement in the futureOli Woodman/Immediate Media
5. Slide the stem back onto the steerer tube and replace the spacers you just removed into position above the stem.
If there’s a large stack of spacers above the stem, consider whether flipping the stem could achieve the same effect to the fitOli Woodman/Immediate Media
Ensure there is a 3 to 5mm gap between the steerer tube and the top of your stem/spacer. This will ensure there’s enough space for the headset topcap to clamp down and preload the headset bearing.
If this gap is not present, check that you have not misplaced any spacers.Oli Woodman/Immediate Media
6. Now replace that topcap and bolt and tighten till you feel some resistance. This topcap bolt is used to preload the headset bearings.
Too tight and your handlebars won’t turn freely, too loose and you will feel a rattle and vibration through the bike.Oli Woodman/Immediate Media
7. Next, align the stem with the front wheel, so the bar is at a right angle with the wheel. This may take some patience – it helps to straddle yourself over the top tube of the bike.
This step may take some patience – it helps to straddle yourself over the top tube of the bike.Oli Woodman/Immediate Media
8. Once the wheel and stem are aligned, evenly torque the stem clamp bolts to the manufacturer’s recommended value using a torque wrench. This is often around 5 to 8Nm.
It is worth investing in a decent torque wrench for jobs like thisOli Woodman/Immediate Media
9. Check your headset adjustment. An easy trick to get this right is to hold the front brake and put one hand on the headset, then rock the bars gently back and forth. Feel for the steerer rocking back and forth inside the headtube of the bike. If you feel this, loosen the stem clamp bolts and tighten the top cap bolt another quarter-turn, then re-torque stem clamp bolts.
Repeat until all signs of bearing movement have disappeared and the handlebars still turn smoothly. If you’ve tightened the bolts too much, you’ll feel a tight spot when turning the handlebars.
If you’re struggling to eliminate play, make sure all headset spacers are account for. Even a few millimeters can make a difference!Oli Woodman/Immediate Media
10. Go and test that new bar height.
Flip the stem
If spacers aren’t enough to achieve the affect you wanted, you can flip the stem to make a further change to the bar height. Most mountain bikes will be set up with the stem in a positive position, creating an upward angle, but you can use it the other way round. This uses all the steps above with the addition of unbolting the handlebar from the front of stem.
11. With the bike’s wheels firmly on the ground, make a mental note of the handlebar angle and the brake lever angle. Undo the bolts that hold the handlebar to the front of the stem. Remove the stem’s faceplate and store it somewhere safe.
If you feel an excessive amount of resistance when loosening the faceplate bolts, don’t be afraid to put a dab of grease on their threadsOli Woodman/Immediate Media
12. Let the handlebar gently droop to the side and now follow the procedure for swapping spacers, outlined in steps 1 to 4 above.
A second person to support the bike can help hereOli Woodman/Immediate Media
13. While the stem is off the bike, flip it over and then slide it back onto the steerer tube.
You can see that the stem has reversed its slopeOliver Woodman/Immediate Media
14. Reinstall the handlebar, replicating the previous brake lever and handlebar angle. Tighten face-plate to manufacturer’s recommended torque (generally between 4 and 8Nm). Ensure that all bolts are done up evenly, a little at a time, and that there is an even gap top to bottom with the face plate once they’re tight. If the gap isn’t even, the handlebar is being pinched.
Uneven spacing can lead to failure of the bolts in the future, pay particular attention to this step
Proceed with steps 3 to 7 above to preload the headset and tighten the stem.
You’re now good to hit the trail and/or road to test out the bike’s new handling characteristics. It may take some trial and error along with patience to find that perfect height, but once you’ve got it, you’ll be far closer to realising the bike’s true potential.