Wahoo Kickr Core: Usage

Carrying on from the first part of the Wahoo Kick Core introduction, this post will show the direct drive smart bike trainer in more detail.

In the first part, the bike trainer was assembled, but the cassette has not been installed yet. The axle adapters also need to be selected and installed, in order to mount the bike. Let's see how this is done.

Without any adapter in place. This recessed area will hold the selected axle adapter.

With the 12 mm thru axle adapter installed, for 142 mm width. If this adapter is reversed, it will be for 148 mm width, which is for boost type MTB.

On the other side, the 12 mm thru axle adapter is installed. This same adapter is used regardless of whether the bike OLD is 142 or 148 mm.

With the cassette installed! I selected a Shimano 105 CS-R7000 11-28T 11 speed cassette, as it is cheaper and does not wear out as quickly as a titanium Dura-Ace cassette. Any additional weight is irrelevant on the bike trainer.

View of the bike trainer with the cassette installed.

When plugged in, the indicator lights will turn on. This bike trainer can connect via ANT+ or Bluetooth.

Comparing the axle height from the ground, between the bike trainer and the actual bike. I'm surprised to find that the actual height of the bike trainer is slightly lower than the actual bike!

Cervelo Aspero installed on the bike trainer! I placed a spacer between the rear brake pads, so that the piston does not pop out if I accidentally press the brake lever with no rotor in place.

Due to some differences between the bicycle wheel freehub and the bike trainer freehub, there may be a need to adjust the rear derailleur index position when switching between the wheel and the trainer. With a Di2 rear derailleur it is easy, you just need to take note of how many clicks to adjust it. With a mechanical rear derailleur this can also be done, you just need to take note of how many clicks is needed to adjust the barrel adjuster on the rear derailleur.

When the bike is installed on the bike trainer, the RD position needs to be offset outwards for proper indexing. This will vary between bikes.

Full view of the bike on the bike trainer. A front wheel block is not necessary as the rear axle height is almost the same as the front axle height.

A direct drive bike trainer uses the same drivetrain on the bike, just with a different cassette that is on the bike trainer.

The good thing about the bike trainer is that it can be switched between different bikes easily, provided the axle requirements are standard (130/135 mm QR or 142/148 mm E thru), and the number of speeds are the same.

Therefore, it is easy to put on the Dahon MuSP folding bike as well, as it has a 11 speed drivetrain too.

1x11 speed Dahon MuSP on the Wahoo Kickr Core bike trainer. The axle adapter needs to be switched to the 130 mm QR type.

Closer view of the bike mounted on the bike trainer. The rear wheel is higher up than usual due to the different wheel sizes.

The rear axle to ground distance is measured to be about 33 cm.

Using the front wheel block and a suitable book, the front axle is propped up to roughly the same height as the rear axle. I think a difference of +/- 1 cm should be fine.

Getting ready for a ride on Zwift! Water bottles and a towel is a must, while a good fan is strongly recommended.

The Wahoo Kickr Core provides the controllable power meter and also the cadence. Heart rate is via my Samsung Galaxy watch which can transmit heart rate over Bluetooth. Both the watch and bike trainer connects to my phone.

After a good tough ride! If you don't already know, a Zwift ride is usually tougher than outdoor rides as you can't rest at all.

Check out the gradient! This is pretty much my max effort as my heart rate is already so high.

Another one of the weekly West Coast Riders virtual ride.

Other than joining others on virtual rides, it is also possible to ride structured workouts on Zwift. What it means is to choose one of the pre-determined workouts, where the power and cadence targets are set for you. You can adjust the targets according to your ability. Once done, you can use the ERG mode to control the training effort.

ERG mode is only available on a smart bike trainer, where the software can control the bike trainer to vary the resistance level. Power is basically a function of cadence and pedaling force. You can achieve the same power either by pedaling hard at a slow cadence, or pedaling lightly at a fast cadence.

What ERG mode does is to adjust the resistance such that your power output is constant. For example, if your target power is 175 watts, the bike trainer will automatically provide a certain amount of resistance in response to your cadence. Usually there is a cadence target as well, so you just need to focus on achieving the required cadence, and the resistance will be adjusted for you automatically to hit the power target. There is no need to shift gears in ERG mode.

Training in ERG mode. Note the stable power output at the bottom of the screen. And the horrible 16% gradient as well.

The only way to get such perfect power graphs is via ERG mode. It is very good for consistent training as there is a target to work towards.

So far I am loving the Wahoo Kickr Core, as it works as well as advertised. I shall list out some of the good and bad of this bike trainer.

Good:

1) Quiet. Slight whirring sound, but easily drowned out by the drivetrain sound or the fan. Much quieter than the previous Minoura LR340 bike trainer.

2) Smooth and balanced flywheel rotation, for a freewheeling effect.

3) Easy to connect to my phone and Zwift via Bluetooth.

4) ERG mode is super awesome for consistent training purposes.

5) QR and thru axle adapters makes it possible to switch bikes easily.

6) Works as both a power meter and also cadence sensor.

7) Enables riding regardless of weather.

8) Does not wear out your tire, although it still wears out your drivetrain.

Bad:

1) Heavy at 19 kg. But this is due to the heavy flywheel which is apparently necessary to replicate realistic road feel.

2) Expensive at SGD 1,399.