As expected, the stem performed faultlessly and worked well with the RSR bars Swapping in the aluminium bar onto the carbon stem lost some of the superb feel, demonstrating that it is the carbon ENVE RSR bar that’s responsible for a lot of the benefits we observed. Steering was beautifully precise and accurate without any hint of harshness. When compared back to back with an aluminium stem and bar, the carbon cockpit was in a different league – filtering out high frequency vibrations exceptionally well. When paired with the new ENVE RSR bars the cockpit felt exceptional. In fact, when it comes to steering accuracy and vibration damping, handlebar choice has a much larger impact on performance. Analysing the performance of a stem is always tricky, as unless they show a catastrophic failure most short stems do a great job. We tested the stem in combination with ENVEs new HDR bars (full review coming soon) in the 40mm length. All the mounting bolts are titanium We paired the stem with the new ENVE RSR bar for testing We ran the stem on various bikes and with various bars We used anti-slip paste on the steerer and encountered no issues with slippage while riding. ENVE also recommend that a spacer is used both below and above the stem to ensure enough contact to avoid slippage. ENVE retain a cold-forged aluminium face plate to reduce the clamping torque required on the handlebar, but care is needed to ensure that the top and bottom gap on the faceplate is even. We found that it is a very tight fit around the steerer, and care needs to be taken to ensure that the correct torque is used to avoid stressing the carbon threads. Initial setup was a little more involved than with a normal stem. The stem is available in 40, 50, 70 and 85mm lengths The ENVE Mountain Stem is manufactured from uni-directional carbon fibre and the bladders have been removed from the material to maximise the weight/strength ratio.

Previous carbon stems have used so much material that the weight saving is negligible. Stems are generally stressed from all directions through bending, torsion and shear forces and often it’s hard to extract the maximum weight saving properties of carbon fibre, which is strongest in one direction. All the ENVE Mountain Stems are produced in Ogden, USA and made of 100% uni-directional carbon fiber The +/- 6 degree rise and flip-flop graphics mean that the stem can be run upside down if needed to lower a high front end, and the 37 mm stack height is nice and compact. The stem uses the standard 31.8mm bar clamp and comes in lengths of 40, 55, 70 and 85mm. The faceplate is manufactured out of cold forged aluminium for better clamping reliability However, considering that the stem is made entirely in house in Ogden, Utah and includes titanium M5 bolt hardware and cutting edge carbon manufacture to squeeze out every last gram, you can start to see why the price is sky high. Producing a product that is 30% lighter than the established competition is never cheap, and the Mountain Stem is indeed frighteningly expensive at €280. With most premium short stems weighing around 140-150g we were blown away that ENVE have managed to trim down their Mountain Stem to just 86g (in the 40mm version tested). The ENVE Mountain Stem is one of the lightest on the market at 86g A good stem needs to be stiff, reliable and hold the handle bar in place securely, and if it’s light that’s a bonus. Sitting in the middle of the chain between rider and bike, not only does the stem transfer all the riders weigh and inputs down to the wheels, but its stiffness and compliance play a large factor in steering feel. When it comes to upgrading it’s easy to overlook the humble stem, however, its function in the cockpit is vital.

The 55mm ENVE Mountain Stem is the pinnacle of desirability, but comes at a cost However, this giant advance in strength/weight comes with an equally giant price tag. After years of R&D the carbon fibre wizards at ENVE have now re-written the rule book and produced the ENVE Mountain Stem, a hard hitting enduro stem that weighs an incredible 86g. Carbon fibre stems are nothing new to the market and have been used for many years on road and XC bikes, but until now we have yet to see a carbon stem that is strong enough for AM / Enduro use.

Best mtb stem