PowerTap G3 Hubs FAQ
Which bicycle computers are compatible with my G3 Hub?
The PowerTap G3 Hub is both ANT+ and Bluetooth SMART compatible, so the power meter can be used with any ANT+ cycling computer or a smartphone.
How accurate is the G3 Hub?
The G3 Hub is accurate to within +/-1.5%. Most direct force power meters claim anywhere from +/-2% to +/-1%, so the G3 is right in line in terms of accuracy.
How much does the G3 Hub weigh?
The G3 weighs 325 grams.
Does the G3 automatically transmit cadence data?
Yes, the PowerTap G3 Hub automatically detects and transmits cadence data to your head unit. In addition, because it is a hub-based power meter, it is able to transmit speed data as well – a nice bonus feature.
Does the G3 work with road and mountain bikes?
No. The G3 is intended for road bikes only. PowerTap makes the PowerTap G3 Disc Hub which can be used for mountain bikes.
What warranty comes with the G3?
The PowerTap G3 Hub comes with a standard 2-year warranty.
How can I tell if my hub is 11-speed compatible?
All 11-speed compatible freehubs for Shimano/SRAM are black. All Campagnolo hubs are 11-speed compatible and are champagne color.
If you are looking to upgrade to 11 speed Shimano/SRAM, make sure your hub uses a 15 mm axle. If you have a 15 mm axle, you can purchase the 11 speed freehub body.
What length spokes do I need to build my new PowerTap G3 hub into my rim?
You will need to enter the rim measurements (ERD), along with the correct PowerTap hub dimensions, and the cross pattern into a spoke calculator to determine the necessary spoke length. Please note: drive and non-drive side spokes are the same length.
Does the G3 Hub measure independent left and right power?
No, the G3 measures total power, but not independent left and right power.
How do I update my G3 hubs’ firmware?
As of 4/22/14 you can update the Powercap on a Mac with PowerAgent 7.7.5.
- Spin the wheel/axle a couple times with the Powercap still on to “wake up” the Powercap
- Take Powercap off by removing the triangular nut and pulling Powercap straight off (do NOT twist)
- Remove the CR2032 battery from the Powercap
- Plug the Powercap without the battery into your computer using a micro USB cable
- Open PowerAgent
- Navigate to Tools > Firmware > Check for Firmware Update
- Click OK to begin the firmware update
- Firmware will install. With some new versions of firmware, Window OS will need to “re-find” the attached PowerCap. Let it run to completion.
- When PowerAgent says the update was successful, click OK and unplug Powercap
- Wait 10 seconds, plug battery back into the Powercap
- Install PowerCap back on PowerTap hub
Which phones or tables work with the BLE PowerCap?
For phones you can use the iphone 4S or higher. Iphone 4 and lower does not have integrated Bluetooth 4.0. The BLE PowerCap will work with ipad 3 or higher tablets and Android tablets with Jelly Bean OS 4.3 or higher.
How do I install the G3 Hub?
If you buy the stand alone hub you will need to have your local bike shop lace it into your existing wheel set – or you can do it yourself if you’re handy with wheels. If you buy a completed wheel set, you will pay a bit more, but installation is as simple as swapping out your old wheel for a new one – and power meter installation doesn’t get any easier than that.
What type of battery does the G3 Hub use?
The PowerTap G3 uses a standard coin cell CR2032 battery. There is a USB connection, however it is used for service and for firmware updates only. The hub should not be left connected to the USB port for long periods as doing so could drain the battery.
How long does the battery last?
Battery life for the G3 Hub is approximately 200 hours.
How difficult is it to change the battery?
The battery can be accessed by removing the cap on the non-drive side of the hub, using a PowerTap hub cap removal tool (included). One you have the cap removed, you will see the CR2032 battery which is housed into the cap from its side. Simply pull the old battery out (sometimes pliers help) and put the new one in. Take special care when reinserting the cap as the electronics have to be aligned properly.
Can I manually zero or auto zero the G3?
Yes. We recommend that you perform a manual zero before each ride. The G3 Hub will also self auto-zero while coasting – which will help keep it calibrated at all times.