Stems

How much does a stem change the handling?

The stem connects your handlebars to the steerer tube and has an outsized effect on how the bike handles. Length, rise and clamp diameter all matter — and unlike most components, the "best" stem is entirely dependent on your bike's geometry and your body proportions.

What stem length should you run?

Modern MTB stems range from 30mm to 80mm. Shorter stems (30-40mm) are standard on enduro and DH bikes — they quicken steering response and move weight rearward. Trail stems (40-50mm) balance steering speed with climbing stability. XC stems (60-80mm) provide reach and weight the front wheel for climbing traction. If your bike feels twitchy, try a 10mm longer stem before changing anything else. If it feels slow to turn in, go shorter.

Does stem rise matter?

Most MTB stems are 0° (flat) or have a slight positive rise. Negative rise (sloping downward) is an XC race thing — it lowers the bars for an aggressive position. If you need more bar height, consider a high-rise handlebar before adding stem rise; it achieves the same result without the visual awkwardness of a steep upward-angled stem.

31.8mm or 35mm clamp?

Two handlebar clamp diameters exist: 31.8mm (standard, still common on XC) and 35mm (now dominant on trail, enduro and DH). 35mm bars and stems are stiffer and stronger for a given weight. Make sure your stem clamp matches your handlebar clamp diameter — a 35mm bar will not fit a 31.8mm stem. The steerer clamp is universally 28.6mm (1-1/8") on the upper portion where the stem sits.

Which stem material is worth paying for?

Forged alloy stems from brands like Hope, Burgtec and Renthal are machined from a single billet — strong, precise, and available in various anodised colours. Cast alloy stems are cheaper but heavier. Carbon stems save 20-40g but cost significantly more and can crack from crash impacts. For most riders, a quality forged alloy stem is the best balance of weight, strength and value.