MAX. POWER ON Motor Bosch Performance Line CX - Smart System 85 Nm

[Maco]

Hi, eMTB
(Motor Bosch Performance Line CX - Smart System 85 Nm, Battery Bosch PowerTube 750 Wh, Display Bosch Kiox 300)

It is normal for the motor to give a power of 400-550W at a moment. My friend has the same bike, but her motor does not go over 250W (Pictures are attached) ?

I ask this because my motor turns off several times while driving. They replaced the battery, but I'm not sure if that's the solution.

it is normal for the motor to give a power of 400-550W at a moment ?
My friend has the same bike on the same ride, but her motor does not go over 250W (pictures are attached).
I ask this because my engine turns off several times while driving. They replaced the battery, but I'm not sure if that's the solution.
Can someone send me pictures of the Bosch Flow-power ?

 

[Matt van]

The watts is related to the speed so 250w is like 25kph cut off speed for the motor. You can go quicker but its just you pedaling . and the nm is how quick it gets there.

 

[yorkshire89]

Is this motor power or rider power? I don't have the smart system but my display shows me rider input in Watts.
The Bosch motor can give peak power around 600w for info.

I think your issue is unrelated to what you are seeing and should be going back to Bosch for more diagnostics if not resolved.

 

[Zimmerframe]

The watts is related to the speed so 250w is like 25kph cut off speed for the motor. You can go quicker but its just you pedaling . and the nm is how quick it gets there.

Didn't you just make a post saying that you didn't understand power/torque and so on ??

Understanding motor power ?

Hi guys Im a bit confused at the ratings of the motors. the Bosch cx 4 has 85nm of torque is that always there in all levels or is it 50% 42.5nm of that on eco and upto 340% 289nm in turbo or how is it calculated? and the 250w "speed" is always constant? TIA

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It is normal for the motor to give a power of 400-550W at a moment. My friend has the same bike, but her motor does not go over 250W (Pictures are attached) ?

I ask this because my motor turns off several times while driving. They replaced the battery, but I'm not sure if that's the solution.

Your motor shouldn't turn off. I think it can shut off for over heating, but it's unlikely. It's more likely your battery mounting needs adjusting, or there's a cable not connected somewhere correctly or is getting squashed/pulled somewhere.

I've not used the flow app. Are you sure the power numbers being shown are motor power and not rider power ?

 

[Matt van]

Motor

 

[Matt van]

And yeah i only half understand it

 

[Maco]

So my next question is does anyone know what the Bosch Flow app measures under power ?
Motor power or rider power ?

 

[yorkshire89]

I'm going to assume thats rider power. You can test it out by doing a gentle pedal but using turbo to see if it shows a higher wattage.

 

[Shark58]

The Flow app definitely display rider power. During a ride you should see momentary rider power on the display and after the ride you will see max and average rider power from that ride.

There is no info about motor power available on the display or the app.

The max mechanical power for a Bosch CX Gen4 motor is 680 watts.

 

[Ark]

The power numbers are based on the riders output measured by the power meter built into the motor.


with the bike powered on but no assistance it probably still shows you a power number output on the display
Here's my last ride as you can see I have some big spikes in there too

Taken from Strava so looks different to flow app. but it's logged direct from the motor

The only times your motor should stop is when you hit whatever the speed restriction is for your country.
for me in the UK it's 15.5mph but I can sit around 16.5mph before it feels like it's stopped.
I think the motors are + or - 10% tolerance on the speed restrictor limit so I guess some motors are "lucky" and some aren't.
it's also a staggered off so you don't really notice it as the power fades out

 

[Uktonyb77]

The wheel size on the bike and how the dealer configured wheel size in Bosch diagnostics would also reflect when the speed restrictor cuts in. If configured wrongly and in your favor then the motor doesn’t cut till around 16.5 ish mph . That’s from my own experience.

 

[cappuccino34]

FYI, if you adjust the wheel size in the app it affects the speed that the bike thinks it's doing, so the speed when at the limiter on the Bosch display won't change. To see Actual speed you need an external device such as a GPS.

 

[Shark58]

, so the speed when at the limiter on the Bosch display won't change.

The opposite is correct.

The user/dealer adjustable wheel size only changes the displayed speed. There is a limit of +/- 5% from the original size value.

The motor has a second wheel size programmed which is used for the cut-off limit from the motor. Only a Bosch representative in cooperation with the bike manufacturer can change that value.

 

[cappuccino34]

The opposite is correct.

The user/dealer adjustable wheel size only changes the displayed speed. There is a limit of +/- 5% from the original size value.

The motor has a second wheel size programmed which is used for the cut-off limit from the motor. Only a Bosch representative in cooperation with the bike manufacturer can change that value.

You're talking about a different variable.
Production variable vs user variable.
There's a limit to the degree of adjustment that the user can make, which is intended for different tyre options that the user might fit.

The production variable is for the fitted wheel size and that isn't user adjustable.

Both values affect the bike's concept of speed, but by potentially differing amounts.

 

[Ark]

you can change the wheel size in the flow app, it doesn't do anything but change the number on the read out so it is displaying the correct speed.

it doesn';t change when the motor cuts out