Inpeak Rechargeable Powercrank-E Shimano Ultegra R8100

The Inpeak Powercrank-E Ultegra R8100 power meter is a single-sided power meter for cranks of the Shimano R8100 series. It measures the power on the left crank arm. The actual power meter weighs only 10g and is well protected on the inside of the crank arm.

The special feature compared to the competition is the rechargeable battery. The battery lasts for a maximum of 90 hours of riding time and is fully recharged after 2 hours on a standard USB charger.

To install the Inpeak Powercrank-E Ultegra R8100 you need the TL-FC16 tool.

Single-sided measurement

With the Inpeak Powercrank-E Ultegra R8100, only the left crank arm is equipped with measuring electronics. The power is doubled to determine the overall performance. Hitting training zones or pacing yourself during a long climb or triathlon usually works very well with a one-sided measurement. It becomes more difficult when one leg is significantly stronger than the other. Then the overall performance deviates. The Inpeak Powercrank-E Ultegra R8100 is therefore particularly suitable for riders who can do without the last percent of accuracy.

Compatible bikes and cranks

The power meter is located on the inside of the crank arm. Therefore, 10 mm space is required between the crank arm and the frame. With direct mount brakes it is often tight. You can use a 10mm allen key to check whether it fits. In the power meter area, the 10mm allen key must fit between the frame and crank arm:

The Inpeak Powercrank-E Ultegra R8100 power meter does not only fit Ultegra series cranks, but also all Hollowtech II road cranks (e.g. Dura Ace or 105).
Therefore, you can simply bring the Inpeak power meter to a training camp, as most rental bikes are also fitted with Hollowtech II Shimano cranks. So you don't have to do without watt-controlled training there either.

Compatible bike computers and smartphones

The Inpeak power meter uses the ANT+ and Bluetooth LE transmission protocols to transmit power, cadence and a variety of detailed performance data. It is compatible with all ANT+ enabled bike computers and smartphones with Bluetooth Smart technology. Thanks to Bluetooth, the power meter also works with Zwift, TrainerRoad, Rouvy, The Sufferfest and other indoor training apps.

Construction and design

The flat, waterproof and robust housing is specially designed for racing bikes and gravel bikes. The actual power meter is well protected on the inside of the crank arm.

Battery

The special feature compared to the competition is the rechargeable battery. The battery lasts for a maximum of 90 hours of riding time and is fully recharged after 2 hours on a standard USB charger. A corresponding USB charging cable with magnetic clip is included in the scope of delivery.

Weight

At just 10g in addition to the crank arm, the Inpeak power meter is one of the lightest power meters on the market.

Accuracy

The measuring accuracy is +-2%. However, the measurement accuracy must be put into perspective, as the measurement is only taken on the left side.

Cadence

The cadence is measured with an acceleration sensor and transmitted to the bike computer or smartphone. An additional cadence sensor is no longer necessary.

Temperature compensation

If temperature changes, different materials expand differently. This can have a considerable influence on the measuring accuracy of a power meter. Precise and accurate measurements are guaranteed by automatic temperature compensation from -5°C to +50°C.

Calibration

Each Inpeak power meter is calibrated individually at the factory in Poland. Zero calibration (also known as “zero offset” or “manual zero”) is a different matter and should be carried out before every ride. This is similar to a scale, which also has to be “zeroed” before you step on it. For zero calibration, the Inpeak power meter must be active and connected to the bike computer or smartphone. Zero calibration can be performed on the bike computer or smartphone.

Setup / Firmware Updates

Unlike other power meters, the Inpeak power meter does not need to be specially set up or registered. The correct crank length is already stored in the power meter. The Inpeak app (Android & iOS) and a smartphone are required for firmware updates. We recommend that you always use the latest firmware for the power meter and bike computer.

Installation

Fitting the Inpeak Powermeter to your bike is very simple. The left crank arm of your crank is simply replaced by the Inpeak crank arm. For the Inpeak Powercrank-E Ultegra R8100 power meter you need a 5mm allen key and the Shimano TL-FC16 crank assembly tool. This is used to loosen the fixing bolt that pulls the left crank onto the axle. If you don't already have it, it's best to order it now.

Durability

We have had excellent experiences with the durability of Inpeak power meters. The complaint rate is extremely low. The power meter is well protected against mechanical influences due to its position on the inside of the left crank. In the event of a crash, for example, a pedal power meter usually takes a knock. This is where Inpeak scores points.

Warranty and support

The Inpeak Powermeter comes with a 2-year manufacturer's warranty. The Inpeak power meters are manufactured in Poland. Should there ever be a problem, we have a direct line to the manufacturer and can help you quickly.