There are several factors that affect the handling of a mountain bike. One of these is the stem. Length is one of the first things to consider when choosing a stem for your MTB.
A mountain bike stem is the part of your bike that connects the handlebars to the fork steerer. Stem length is measured from the center of the headset stem cap bolt to the center of the handlebar. The average mountain bike stem length is between 50mm and 80mm.
This article will cover everything you need to know about mountain bike stems and how to choose the optimum length to suit your needs.
How Does Stem Length Affect Mountain Bike Handling?
With a shorter stem, your bike has quicker handling and a more responsive feel. A shorter stem is preferred for cyclists with longer and slacker bicycles. With a shorter stem, your weight is shifted backward, preventing you from dumping over the handlebars. This length is also ideal for downhill, trail, and enduro riders. Downhill cyclists enjoy a 40-50mm long stem.
A longer stem puts you in a better pedaling position which can come in handy during uphill cycles. This is because it shifts your body weight forward onto the front wheel. Cross-country riders prefer long stems in the 80-120mm range to increase the stretch in their positions. Long stems stabilize the steering of a bike, giving the rider more confidence when riding at high speeds.
This is the angle that the stem makes relative to the fork steerer tube. If you are looking to get a higher front-end height, you should get bars with a larger rise angle. With time, more riders have opted for shorter stems. These have very little distance to travel both upwards and downwards, so the rise angle doesn’t make for much.
Rise is considerable when it comes to bikes with longer stems. This is because of the distance that it has to shift the handlebars. Most stems have a rise of either 6°. Zero-rise clamps do not change the bar height when you flip them. A 6-degree rise stem lets you change the height of the bar by 6 degrees when you flip the stem upside down.
You may have to try your hand with different stem rises to find the one that gives you the most comfort and the best pedaling. Different riding styles also come in handy when deciding the best stem rise for you.
- Downhill riders prefer a 0-degree rise since raised handlebars raise the center of gravity.
- Trail and enduro riders usually enjoy a rise between 0 and 6 degrees.
- Most cross-country riders prefer a drop ranging between 0 and 30 degrees.
This feature refers to the clamp bolts that are used to fasten the stem to the other parts of the bike. A stem has a clamp for the handlebar at the front and a clamp for the fork steerer at the back.
Bar clamps come in two options; the 2-bolt and the 4-bolt design. Most stems use the 4-bolt design, which is more preferred because it offers more strength, stiffness and it is less creak-prone.
The rear clamp mostly uses the 2-bolt design. However, some downhill bike stems use a big single bolt, and some cross-country bikes use a wedge design that has the bolt in front. When it comes to the rear clamp design, ensure that the clamp bolt heads don’t project so far back. This is because they are likely to smash into your knees in case of an accident and that isn’t a feeling you want to experience.
This is the diameter in the middle of the handlebar, where the stem clamps onto it. Before you buy a stem, you have to ensure it is compatible with your handlebars. Most mountain bike handlebars use 35mm clamps, but there are 3 clamp diameters on the market: 24.5mm, 31.8mm, and 35mm.
Larger clamp diameters provide more durability, stiffness, and strength while reducing the clamping pressure required. You can easily use a tape measure to check the diameter of your stem.
Most bike stems are fashioned out of aluminum alloys. The cheaper ones are made from weaker grades like 6061, but more expensive ones are made out of grade 2014 aluminum, which is lighter and stronger than the 6061. Some stems are made out of steel, which are cheaper than the aluminum ones.
Some stems are made of carbon fiber. This material is lighter, but this might not be reason enough to spend the extra money, considering that carbon bike parts require more frequent check-ups. Competitive racers who need to cut weight might consider it, however. Some CNC machined aluminum stems give you the fancy look without leaving a dent in your pocket.
Titanium stems were all the rage in the 90s, but they have made a recent comeback. There is a negligible difference in weight when compared to the aluminum stems, but the price difference is noticeable.
How Do You Measure the Length of a Mountain Bike Stem?
If your bike stem is damaged, or you feel the need to have it replaced, you need to know the length of your stem. You can get this measurement easily, using your ruler/tape measure.
- Find the headset. This is the part at the top of the steering head which holds the steering column.
- Measure the length from the center of the headset to the center of your handlebars.
if your tape measure doesn’t have the metric system, you can multiply the inches value by 2.54.
Mountain Bike Stem
This is a short handle stem, with a length of 45mm. The stem maintains an aesthetic appeal as it is constructed of CNC machined 6061 aluminum alloy. The stem is available in black, blue, gold, and red. It is suitable for use with handlebars with a 31.8mm diameter and a steerer tube with a 28.6mm diameter. The stem has a modern four-bolt clamp design.
This is a high-intensity stem and it is most suitable for downhill riders, thanks to its zero -degree rise.
This is a rather long bike stem, with the center distance between the 2 holes being 110mm. This stem is popular among uphill riders, given its +/- 35-degree rise angle, which gives extra comfort. It is perfect for cyclists looking to cut weight but maintain durability.
This stem was built to withstand rough terrains and high impact, thanks to the 6061 aluminum alloy used to forge it. This quality is not affected by the stem’s lightness, as it weighs a little over 200g.
This stem falls on the shorter side, and it is available in three lengths, 40mm, 50mm and 60mm. This feature, combined with its zero-degree rise angle make the stem suitable for downhill and freeride riding. The stem is compatible with 31.8mm handlebars.
The BW stem is a stable and strong addition to your bike’s parts. With its aluminum alloy composition, it provides strength and robustness. This product is available in many variations and you are sure to find your fit.
The stem is fairly long, and it can be found in 90,105, and 120mm lengths. You also have a choice when it comes to the rise angle. This stem comes with either a 10 or 35-degree rise.
This product is also made of high-intensity CNC forged aluminum alloy. At 280g, this 110mm long stem is light but heavier than other stems reviewed.
The stem is available in 31.8 and 25.4mm handlebar clamp diameters and a 28.6mm front fork diameter. It has a knob for adjusting the rise and it ranges from 0 to 60 degrees. This stem has an easy installation procedure with its 4-bolt clamp design.
This bike stem was designed to offer strength, stiffness, and weight. It is fashioned from 6061 aluminum which gives it resistance. The stem is available in 45mm (195g) and 60mm (215g) length and a 10-degree rise angle. It has faceplates, which reduce the stress that could cause your bar to bend or break.
At 35mm long and zero-degree rise, this stem is ideal for downhill riders. This stem weighs 203 grams of 6061 aluminum alloy. This stem can be used with a handlebar with a 31.8mm diameter and a steerer tube with a 28.6mm diameter.
Unlike the other FOMTOR stem, this one is more suited for downhill bikers. The stem has a handlebar center diameter of 31.8mm and a steerer tube diameter of 28.6mm. It is a durable, lightweight stem weighing in at 115g and it is available in 3 lengths, 60mm, 70mm, and 90mm. The 4-bolt clamp system used also makes installation an easy task.
This bike stem is fit for all mountain bikes provided that its handlebars have a center diameter of 31.8mm and a fork diameter of 28.6mm. This stem is 45mm long, with a 4-bolt clamp design. It is available in five colors and sells for $9.99.
10. RXL SL stem
Unlike the other stems reviewed, this stem is made out of carbon fiber, with an aluminum alloy. The stem is 80mm long and it weighs around 130 grams. Another feature of this bike stem is its +/-6 degree rise and it fits a 31.8mm wide handlebar diameter and 28.6mm fork diameter.
This stem is available in 6 colors and 3 different appearances.