The PRO Tharsis 3Five CNC Stem is purpose-built for aggressive trail and all-mountain riding. CNC machined from a solid block of 7050 aluminium, this 55mm, zero-rise stem delivers a stiff, direct connection between your hands and front wheel — so every input translates immediately into precise steering response.

Highlights

• CNC machined 7050 aluminium: milled from a solid billet for maximum stiffness and consistent geometry with no casting voids.
• Oversized 35mm bar clamp: four-bolt removable faceplate pairs with 35mm handlebars for a notably stiffer cockpit than 31.8mm setups.
• Short 55mm length: positions your weight forward and keeps the front end lively on climbs and technical terrain.
• Zero-degree angle: provides a neutral, predictable ride position suited to modern trail geometry.
• 2-bolt steerer clamp: secures to 1-1/8 inch threadless steerers with an even, reliable clamping force.
• 40mm stack height: compatible with standard spacer setups for dialling in your preferred bar height.
• Black anodised finish: clean, durable look that integrates with a modern trail cockpit.

Engineered for stiffness

PRO designed the Tharsis 3Five CNC with a blocky, reinforced body profile that prioritises rigidity over weight. The result is a stem that stays composed under hard braking, resists flex through rough and fast trail sections, and gives you the confidence to push harder. The 35mm bar clamp diameter is central to this — the wider interface spreads load across more material and reduces the torsional flex that can blunt steering feel on big hits.

The Tharsis 3Five system

The Tharsis 3Five CNC Stem is designed to work as part of PRO's wider 35mm cockpit system. Pair it with a PRO Tharsis 3Five handlebar for a fully matched, stiff front end built around the oversized 35mm standard. The 55mm length suits riders running slacker head angles and longer front centres on contemporary trail and enduro frames.

Compatibility & Fit

Handlebar clamp diameter: 35mm (requires a 35mm clamp handlebar — not compatible with 31.8mm bars). Steerer clamp: 1-1/8 inch (28.6mm) threadless, 2-bolt. Length: 55mm. Angle: 0 degrees. Stack height: 40mm.