Types Of Bike Stems: How To Choose Your Bike Stems

Threadless, direct mount, or internal routing? Here’s how the main types of bike stems differ — and how to match dimensions, material and rise to your bike.

The 3 Main Types of Bike Stems

Threadless Stems

The modern standard. A threadless stem clamps to the outside of the fork’s steerer tube and comes in a wide range of lengths and angles, so you can fine-tune fit and handling for XC, trail or all-mountain riding. From Funn: the Equalizer, Equalizer Zero, Crossfire, Funnduro, Tron and Stryge.

Direct Mount Stems

Bolts straight onto a dual-crown fork for downhill and freeride — shorter, stiffer and more precise under heavy loads. From Funn: the RSX.

Internal Cable Stems

Routes cables through the stem body for a clean cockpit. More common on XC and endurance bikes than gravity rigs.

RSX Direct Mount Stem

Aerospace-grade AL6061, World Cup proven — built-in 45/50mm length adjustment for dual-crown forks.

VIEW RSX

Stem Dimensions: What the Numbers Mean

Bar Bore (Clamp Diameter)

Match the clamp to your handlebar: 31.8mm is the long-running all-round standard; 35mm adds stiffness for aggressive riding like downhill and enduro.

Steerer Tube Compatibility

Most modern bikes run a 1 1/8" (28.6mm) steerer. Older or specialty bikes may use 1", 1 1/4" or 1.5" — measure yours before buying.

Stack Height

The vertical space the stem occupies on the steerer. It sets how high your bars can sit — check it against your steerer length and spacer stack.

Stem Length

Short means quick handling for steep terrain; long means stability and climbing efficiency. DH runs short, XC runs long, trail and enduro sit in between.

Rise and Drop

Positive rise lifts the bars for comfort and control on rough terrain. Negative rise (drop) lowers them for a faster, more aerodynamic position. Zero rise splits the difference. Reversible designs like the Equalizer give you a 10mm rise or a 10mm drop from the same stem — flip it to change your setup.

Equalizer Stem

EWS-grade and reversible — run it as a 10mm rise or a 10mm drop. 35, 42 and 50mm lengths.

VIEW EQUALIZER

Stem Materials

Aluminum

The standard for good reason: strong, light and affordable. 6-series alloy — used across the Funn stem range, from Equalizer and Crossfire to Funnduro, Stryge, Tron and RSX — balances durability, corrosion resistance and price. 7-series is stiffer and lighter, at a higher cost.

Carbon Fiber

Lightest and best at damping vibration, favoured by racers — with the price tag to match.

Steel and Titanium

Steel is heavy but nearly indestructible, a touring favourite. Titanium blends strength, low weight and corrosion resistance — mostly seen on custom builds.

Before You Buy

Double-check the two clamp sizes (steerer and bar bore), make sure the stack height works with your steerer, and fit the stem with the right tools at the specified torque.

Conclusion

Pick the type that matches your bike, then dial in the dimensions — clamp size, length, rise — and the material that fits your budget. The right stem makes the handlebar feel like a natural extension of the bike.