Eurobike Tech: Pro’s new Di2-ready mountain bar and stem, alloy TT setup
New Tharsis XC stem includes an integrated headset compression system and a new Di2 battery hiding spot
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If you’re going to spend the money on the latest in posh mountain bike drivetrains, Shimano’s XTR M9050 Di2, then you won’t want wires hanging haphazardly around your cockpit.
To help the neat freaks tuck away their Di2 wires, Shimano-owned Pro Components has introduced a new line of Tharsis components, including a new stem, handlebar, and seatpost.
The new Tharsis XC line will replace the Tharsis XCR line. The Tharsis Trail line remains untouched.
The Tharsis XC Handlebars and Tharsis XC Stem are where most of the new integration is found. The handlebar has specific cutouts for internally routing Di2 E-Tube wires. The stem takes integration a step further and uses a new headset compression system that incorporates an expander into the stem to snug up the headset, eliminating the need for a starnut in the steer tube. That frees up space for an E-Tube internal battery placed inside of the steerer tube.
We have not received a Tharsis XC Stem, and the press-release was a bit vague on how the system works exactly, but it appears to be a similar to Acros headset used by German brands Focus, and Canyon, except that this stem should work with any headset; just remove your star-nut and go. We’ve had some issues with the Acros expanding headsets in the past — they tend to work themselves lose over time — but hopefully Pro has solved that problem.
The weight for a 100mm stem is 138 grams, which isn’t a featherweight, but that includes the compression system. Some star-nut systems are meaty, so there could be weight savings if riders want to upgrade their current setup. The Tharsis XC Stem will be available in lengths from 70mm to 120mm and in two angles; -6 and -17. However, the 70mm is only available in the -17-degree option, and the 120mm is only available as a -7.
The Tharsis XC Handlebars will come in three shapes: Flat with a 700mm width, Flat Top with 5mm of rise a width of 720mm, and Riser with 15mm of rise and a width of 740mm. Every shape has a 9-degree backsweep and a retail price of $200. Only the Flat Top shape will be available in a Di2 version, which will set you back an extra $20.
The Tharsis XC Seatpost is also Di2 compatible, for those who would rather hide the battery in their seatpost. It’s available with zero and twenty degrees of setback, and in three widths; 27.2, 30.9, and 31.6mm.
At $300, the Tharsis XC Seatpost is a bit on the pricey side, and the weight is nothing earth shattering. However, if you’re the type of rider who’s seatpost, stem, and bar must match — and who could fault you for being that coordinated — you’ll need this seatpost to match your Di2-friendly cockpit.
Budget Missile Alloy aerobars
Pro also announced the launch of a new budget-friendly time trial cockpit. Dubbed the Missile Alloy, the new bar is an aluminum counterpart to the Missile Evo handlebar, which is ridden by many WorldTour teams. The Missile Alloy looks to use some of the technology used in the Missile Evo, sporting a sleek base bar shape.
The Missile Alloy base bar will only be available in a 40cm width, with 3.5cm of drop from the stem clamp to the hoods. The extensions are available in either Ski-bend or S-bend models for $200 each. The total weight is approximately 729 grams for the base bar and extensions, excluding the use of any spacers.