It means that the motor will provide more assistance when you need it the most, especially from standstill and when going uphill.

(Note: the motor is not more “powerful”, since the maximum power (in Watts) is still the same. Yet torque is what gives the feeling of assistance on an e-bike, especially at lower speeds - That’s what matters!). New torque is 45Nm instead of 30Nm on C3.

We understand that C2/3 customers may want the benefits of the 50% extra torque. However, this is clearly impossible for various technical reasons, among others: 

• The axle is slightly shorter, so it won’t fit the width of the Cowboy 1/2/3 frame. 

• The cables and connectors are different 

• The location of the torque sensor is different

• The entire ride feeling is based on a 30 Nm motor, not 45 Nm

• etc.

The choice was between a torque sensor in the bottom bracket and a torque sensor in the freewheel.

A torque sensor in the bottom bracket needs to sense the torque on both side of the bracket (left and right crank) which makes for a very complex part. It’s hard to design around, is expensive and has very few suppliers.

A torque sensor integrated in the freewheel means all the force is transmitted on one side so it is simpler. It allows for using a normal bottom bracket which is easier to integrate and more reliable. However, it’s quite far from the controller which leads to a more complex wiring and does not provide an “easy” reading of pedalling cadence.

However, this creates challenges in terms of: 

• Wheel assembly: the integration of the torque sensor in the motor forces us to use an asymmetrical rear wheel design. In order for the wheel to be true, we need to use spokes of different length and tension on each side of the wheel. This is quite complex to assemble and to get right

• Reliability: we saw more damaged bearings of the freewheel than we hoped for, leading to too many interventions on these parts. The 'clutch issue' is also an indirect consequence of the torque sensor integration in the wheel.

We have moved the torque sensor back to the bottom bracket on Cowboy 4, for the reasons above.

This is also the case on Cowboy 1(+): the torque sensor is integrated in the bottom bracket.

We deployed an improved mounting system for the C2 and C3 freewheel, with two major reliability improvements:

1. Lower lateral load on the torque sensor bearing

2. Improved bearing shielding to prevent corrosion.

As a consequence, we introduced two spare parts:

1. Torque Sensor Spacer: to be placed between the torque sensor electronics and the freewheel. This means you’ll have to split the inside and outside of the torque sensor when installing this

2. Bearing shield: to cover the torque sensor and held in place by the sprocket lock ring.

We’ll start shipping these parts for all wheel-related repairs - In parallel, we are shipping of safety stock of 10 parts (5 of each) to each of you. You should have received an email to validate this order.

Video tutorial for all rear wheel repairs has been updated accordingly - Please watch this video from 10:42 to 14:42 for instructions on how to mount these new parts.

The idea is to separate the torque sensor electronics from their housing, add a spacer in between, then mount the “shield”.

Thanks to the shield, we can also increase the torque on the inner and outer nut of the freewheel kit (5Nm each).

(Cowboy 2/3 only)

Such a noise can come from:

• A misaligned freewheel

• A damaged bearing of the freewheel (either on the motor cover and/or the torque sensor).

Step 1: Is the new freewheel mounting mechanism ("freewheel kit") mounted? 

• We improved the mounting mechanism of the freewheel during the lifespan of Cowboy 2, to mitigate noises coming from a misalignment of the freewheel (see "Noise From Axle / Freewheel misalignment" section below).

• All bikes produced as from October 2019 include this fix by default (i.e. all Cowboy 3, and most Cowboy 2 bikes). Bikes produced before that date should still have the old mechanism, unless we replaced it already.

• If any doubt, ask for a picture of the rear axle on the drive side (you can base yourself on the "freewheel fix" saved reply):

Models Impacted: Cowboy 2 and 3.

Symptom: Cracking noise from rear axle.

Root cause: A bearing of the freewheel, located on the torque sensor, is damaged (either due to misalignment or to water entry, for example). We need to replace it to get rid of the noise.

Countermeasure: CMS to replace torque sensor (+ motor cover if needed)

Preferred interaction: CMS 

Models Impacted: Cowboy 2 and 3

Symptom: "Squeaky" noise from the rear axle and/or resistance in the freewheel.

Not to be confused with:

• Freewheel - Noise From Axle / Freewheel misalignment: due to misalignment of the freewheel linked with the old mounting mechanism

• Torque Sensor - Freewheel Noise from Torque Sensor Bearing: linked to torque sensor bearing problem

Root cause: bearing in the motor cover that becomes damaged over time. It needs to be replaced, usually with the motor cover (in most cases, both bearings tend to get damaged together).

Countermeasure: Replace the motor cover (+ torque sensor if needed)

Preferred interaction: CMS

Possible symptoms: 

• Too much assistance or no assistance - no BIT errors in the back-end.

• Sometimes the bike will present an "auto acceleration" behaviour, where it accelerates even when no torque is applied on the pedals. 

• Sometimes the bike won't deliver enough assistance, requiring a customer to push extra hard on the pedals to get assistance from the bike. If that's the case, use tag "Torque Sensor - Less Assistance due to Low Idle Torque Value", explained below

• This can usually be confirmed by the behavior of the throttle voltage, visible in the backoffice app: 

  • if the throttle voltage is outside of the normal range (0.4V-0.6V when idle, up to 2.0V when pushing hard on the pedals), this can indicate a faulty torque sensor.

  • Also double check that the vehicle speed is behaving normally. If it isn't, this could indicate a faulty speed sensor (which is another issue).

Root cause:  Each torque sensor is slightly different, yet works in the same way: 

• We measure a voltage from the component, which is correlated to the torque applied on the component (on C2 and C3, this torque is transferred to the torque sensor through the belt). 

• The controller determines how much assistance we need to provide depending on the bike speed (measure by the motor's speed sensor) and the throttle voltage from the torque sensor.

If the torque sensor is faulty, this can result in the controller delivering too much assistance (if the torque sensor is oversensitive) or too little/no assistance (if the torque sensor isn't sensitive enough).

Countermeasure: replace the torque sensor

Models: Cowboy 2, Cowboy 3

Symptom: 

• Bike feeling 'slower' or 'less powerful' than before, requiring the user to push harder on the pedals for the assistance to kick in properly. Customers with sometimes report that they feel a bit of a vibration when the assistance kicks in, that it feels less smooth than before.

• This can be confirmed by looking at the idle throttle voltage, we expect it to be lower than 0.4V when idle. 

Root cause: 

• Over a lifetime of a bike, the idle torque value (=throttle voltage) from the torque sensor could change a little bit. In most cases, it will drift down and it could even go outside of the acceptable range of 0.4-0.6V. If that's the case, the customer will need to push harder to reach the same throttle voltage as before, therefore having to push harder to feel the same level of assistance. 

Countermeasure: 

• For now: run a torque sensor recalibration via the Backoffice app and if needed change torque sensor once low idle throttle voltage is confirmed by trip recording

• Mid term, goal is to calibrate the ride feeling based on the torque sensor in each bike. Exact solution TBD.

Cowboy 2/3.

Symptom:

• Assistance failure (no assistance) with a BIT 11 in the back-end (visible by CS)

• Visible damage to the torque cable (e.g. torn off during improper wheel removal by the customer)

Root cause: connection problem between the torque cable and the controller, either due to a bad connection, humidity or a damaged component (usually the torque cable).

Countermeasure: 

• Step 1: unplug the torque cable, clean the connectors and plug it in fully again + check that the cable isn't damaged

• Step 2, if step 1 didn't work: replace the torque cable (a.k.a. "replacement axle")

• Step 3, if step 2 didn't work: replace the controller. The fault could come from the cable on the controller side.

Note: on Cowboy 1, BIT 11 problems are mostly linked with the torque sensor, which is located inside the bottom bracket, not the rear wheel.

Models: Cowboy 1, 2 and 3.

Not to be confused with: 

• Damaged Engine Main Cable (ex: BIT 5)

• Controller - Assistance Failure Linked With BIT 7

--> If a part replacement is required, we normally don't use this tag.

Symptoms:

• No assistance

• BIT 5 or BIT 7 in the back-end (the customer will also see a pop-up in his app)

• Goes away after drying the motor cable connections

Root cause: 

• humidity in the motor cable. Sometimes it can happen when the motor cable isn't plugged in all the way after taking the rear wheel off (e.g. after a puncture).

• Make sure to get as much humidity out of the cable as possible.

Countermeasure: unplug the motor cable, dry nicely (even with a dry cloth or hairdryer), replug and try again. If it still doesn't work,

• BIT 5: change the rear wheel - and use tag "Damaged Engine Main Cable (ex: BIT 5)", not this one

• BIT 7: change the controller - and use tag "Assistance Failure Due To Errors/Faults in the Backend: BIT 2, BIT 7, BIT 9, BIT 12, BIT 13", not this one.

Models impacted: C2, C3

Symptom: No assistance, usually associated with bit 5 error in the back-end. The customer will see a pop-up in the main app inviting him to check the motor cable. 

Countermeasure: 

• First confirm that the BIT error doesn't come from humidity in the motor cable, or from a bad connection. Thoroughly dry the cable and plug it back in entirely. (saved reply "BIT 5").

• If we can't get rid of the problem: replace the rear wheel.

• If the issue persists with a new rear wheel, replace the controller. This probably indicates that the issue comes indeed from the motor cable but on the controller side.

🚨If the BIT 5 is combined with a BIT 14/15 and a BATT TICKING diagnostic, we should treat the BIT 14/15 first. 

Models impacted: Cowboy 4

Symptom: Customer has no assistance - Bit 10 fault in the back-end.

Not to be confused with: Rear Axle - Damaged/Missing Poke Yoke Spacer on Rear Wheel (C4). This can also lead to a bit 10 fault, see specific explanation above. If the BIT 10 fault is a consequence of a broken spacer, only tag the issue as Damaged/Missing Poke Yoke Spacer, do not add this issue tag on top. 

Root cause: broken poke yoke spacer (see above), or another issue with the rear wheel or controller. 

Countermeasure:

1. First check if both poke yoke spacers are still present and not damaged. If they are: see Damaged/Missing Poke Yoke Spacer, explained above.

2. Start by replacing the rear wheel, sharing instructions to the customer on how he can mount it himself

3. If the issue remains: it probably comes from the controller, we can replace it.

Models impacted: Cowboy 2/3

Symptom: When the rear wheel spins, it transmits some force into the cranks which start turning as well, which is normal. This can be noticed by the customer, for example when:

• We walks next to the bike and the pedals turn slightly (that's normal)

• He lifts his feet from the pedals while freewheeling and notices that the pedals spin slowly (that's normal)

• He feels that the pedals are pushing OR he feels vibrations in the pedals when freewheeling (that's NOT normal)

There is always a bit of force transmission, but over a threshold it can become problematic.

Not to be confused with: 

• Freewheel - Resistance/Noise in Freewheel due to Damaged Motor Cover Bearing

Root cause(s): 

As explained above, our freewheel design makes it so that there is always a bit of force transmission from the rotation of the rear wheel to the cranks. As long as it stays below a certain threshold, this is not problematic. 

If this force transmission is too significant, it's likely to be linked with one of the bearings of the freewheel:

• If the freewheel fix was installed by the customer, loosen it a bit (by one quarter turn of the inner nut) to relax it.

• Otherwise, check if the sprocket turns as freely as it should. Change the motor cover and/or torque sensor if adequate

Models impacted: Cowboy 2/3

Symptom: The wheel can spin freely in both directions.
Video HERE

Root cause: There are 3 "paws" in the motor cover. Behind each paw there is a little bend piece of metal acting as a spring. This pushes the paws onto the cogwheel in normal condition (the paws rattling over the cogwheel is also the source of the normal freewheel sound).

Due to dirt or corrosion in the freewheel but also due to an incorrect amount of grease, the paws can get stuck in the retracted position. If they are stuck, then the cogwheel just turns in the motor cover freely in both directions.

Countermeasure: You can try to clean the freewheel and add a small amount of grease. Correct functioning of the paws can be confirmed by simply pushing them with the finger and checking if they come out again reliably. Otherwise, the motor cover has to be replaced.