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The PowerTap G3 Wireless Hub is definitively PowerTap's top offering. Where the earlier generation stood out for its larger-than-normal diameter, this one has a powermeter disguised inside a traditional-looking 57mm flange diameter and subtle matte Black finish. It's also significantly lighter.
In other words, it looks and feels like a regular hub. For reference, Chris King hubs have a flange diameter of 53mm, so the G3 is just a teeny bit larger. And for reference, hubs of Ultegra-quality are around 350g, so the 325g G3 Hub is lighter than all but than the very top-tier rear hubs on the market. Admittedly, there was a sort-of dorky virtue in having a bulky carbon hub that shouted "powermeter," and the individualized aesthetic of PowerTap's older hubs functioned as advertising. However, PowerTap's power-measuring hubs were so obvious it often acted as an impediment for many potential users. The sleek and stealthy design of the G3 eliminates this distraction.
Knowing the value in weight reduction and stealth measuring, PowerTap looked at how to improve its powermeter without any compromise in performance. The G3 design still has a "torque tube" with eight strain gauges, yielding measurements accurate within +/- 1.5%. But PowerTap didn't stop there.
Rather than keep the electronics permanently affixed to the hub shell, PowerTap decided to build the electronics into the end cap. This is a big change, and a welcome one. By having a removable electronic element, it means that if there's a wheel-based problem with power readings, you're able to get a spare cap and install it, rather than sending your wheel back to PowerTap and waiting for the issue to be resolved. Another improvement that comes with this change is that a single CR2032 watch battery powers the transmitter. These batteries are easier to source and replace than the two 357 batteries found in the older hubs. The 2032 should last for approximately 300 hours of riding.
The G3 is equipped with an ANT+ transmitter. This means that the hub sends out a signal that's understood and translated into power, speed, torque, and virtual cadence numbers by any computer head unit that reads ANT+ signals.
The PowerTap G3 Wireless Hub is available in the color Black and is available with spoke drilling for 20, 24, 28, and 32 spokes. The spoke hole diameter is 2.5mm, so it is compatible with conventional round, double-butted, and most modern oval-bladed spokes. The flange diameter is 57mm on both sides. The hub center-to-flange measurement is 38mm for the non-drive side and 17.4mm for the drive side. It's available with a Campagnolo or Shimano/SRAM compatible freehub body. Should you purchase a wheel and need the other style, be aware that they can be swapped easily. After switching freehub bodies, the wheel will not need to be re-dished. The hub rolls on a 15mm-diameter aluminum alloy axle. Along with the hub, you'll get user instructions and the special tool for the end cap on the hub.
Please Note that the G3C Hub does not come with a skewer.
- 57mm flange diameter, 2.5mm spoke-hole diameter
- Shimano/SRAM or Campagnolo compatible freehub
- Works with ANT+ cycling computers
- +/- 1.5% power meter accuracy
- 11-speed compatible