My new Bafang mid drive-am I being stupid?

[DaddyPaddey]

Both my 'bents used torque sensor motors and, as the GoSwiss Drive became too unreliable, it has been replaced with a mid drive Bafang BBS02B which has a cadence sensor.

As I had only ridden using a torque sensor my understanding was that if I had the cadence sensor type whenever I was turning the pedals on level 1 then I would get an extra approx 10% of power, on level 2 20% etc, at whatever speed I was doing up to the 25k cut off.

What seems to be happening is that level 1 gives me the boost to about 8kph, then as long as I am over that speed the power shuts off. Each increase in power level gives an increase in speed before the cut off.

Is ‘that is what it is’ with a cadence sensor type or is something awry, or am I just being stupid?

 

[Dadam]

It sounds like a case of "it is what it is". It seems to be the same with a lot of basic cadence sensor controllers supplied with kits. It was the same on my Woosh kit. I sent them the controller back to look into it, if it was a setting that could be changed, or a new firmware, but apparently they're just like that. They said it might be be fixed by a new firmware from the manufacturer in the future but that wasn't good enough for me so I took the kit off and use a different bike for commuting now.
It should not be the case. My Orbea Gain has a simple cadence sensor and hub motor but the assist level changes the torque output not the cutoff speed. The cutoff is the same 25kmh for all assist levels, as it should be.

 

[CXRAndy]

Both my 'bents used torque sensor motors and, as the GoSwiss Drive became too unreliable, it has been replaced with a mid drive Bafang BBS02B which has a cadence sensor.

As I had only ridden using a torque sensor my understanding was that if I had the cadence sensor type whenever I was turning the pedals on level 1 then I would get an extra approx 10% of power, on level 2 20% etc, at whatever speed I was doing up to the 25k cut off.

What seems to be happening is that level 1 gives me the boost to about 8kph, then as long as I am over that speed the power shuts off. Each increase in power level gives an increase in speed before the cut off.

Is ‘that is what it is’ with a cadence sensor type or is something awry, or am I just being stupid?

If the motor is not seeing the cadence input or the speed sensor rear wheel magnet, the motor will sometimes shut down.

check the alignment of the sensor and magnets

 

[bonzobanana]

Yes lots of cadence sensors are linked to controllers that are speed limited for their power levels. I personally would have expected something better for a Bafang mid-drive motor but I guess it is what it is. Lots of the cheapest nastiest cadence sensor ebikes have stepped speed power levels and to be honest it can be pretty good as you get full power for hill climbing and then the assistance goes away for anything faster. A cadence sensor linked to power levels i.e. torque is more wasteful of power in many ways and shortens the range. Personally I prefer throttles its the main power control method used by most ebikes in the world and you simply control the power as much or as little as you want at all times. It gives the rider full control and is the safest way to control an ebike.

 

[DaddyPaddey]

Yes lots of cadence sensors are linked to controllers that are speed limited for their power levels. I personally would have expected something better for a Bafang mid-drive motor but I guess it is what it is. Lots of the cheapest nastiest cadence sensor ebikes have stepped speed power levels and to be honest it can be pretty good as you get full power for hill climbing and then the assistance goes away for anything faster. A cadence sensor linked to power levels i.e. torque is more wasteful of power in many ways and shortens the range. Personally I prefer throttles its the main power control method used by most ebikes in the world and you simply control the power as much or as little as you want at all times. It gives the rider full control and is the safest way to control an ebike.

Thats helpful. They put a throttle on mine which I turned my nose up at. Actually its proved to be ideal when starting.

 

[DaddyPaddey]

Does anyone know if Bafang do a mid drive using torque sensor?

 

[ebikeerwidnes]

Thats helpful. They put a throttle on mine which I turned my nose up at. Actually its proved to be ideal when starting.

My first ebike was a pre-2016 version so could legally have a throttle
It was nice when starting
but without one you just start it like a bike - as long as the bike is not too heavy then that is just part of the whole "it is just a bike" thing IMO

If I had one with those 1000W motors and a massive battery then I would probably want the throttle for starting as well - but for the legal ones I have ridden then the pedals do just fine

 

[Dadam]

My first ebike was a pre-2016 version so could legally have a throttle
It was nice when starting
but without one you just start it like a bike - as long as the bike is not too heavy then that is just part of the whole "it is just a bike" thing IMO

If I had one with those 1000W motors and a massive battery then I would probably want the throttle for starting as well - but for the legal ones I have ridden then the pedals do just fine

Bikes with torque sensors, even heavy ones, can start immediately with good torque as they can react to the pedal pressure before the bike moves. Cadence sensor bikes usually need half a pedal revolution before they can supply power. This is fine with a lightish bike, but can be a pain with a heavy one especially starting off uphill.

 

[wiggydiggy]

Bikes with torque sensors, even heavy ones, can start immediately with good torque as they can react to the pedal pressure before the bike moves. Cadence sensor bikes usually need half a pedal revolution before they can supply power. This is fine with a lightish bike, but can be a pain with a heavy one especially starting off uphill.

Would activating the walk mode help with that? It instantly powers the bike up to 2.5mph, only difference would be I'd be sitting on it.

 

[Dadam]

Would activating the walk mode help with that? It instantly powers the bike up to 2.5mph, only difference would be I'd be sitting on it.

Yes it should do. I've tried it and it does work but I found the button pushes a bit of a faff. Try it and see.
I thought it was 6 km/h though (3.7mph)?

 

[CXRAndy]

Does anyone know if Bafang do a mid drive using torque sensor?

Yes they do M series have some which are both torque and speed.

M600, M620, M815

https://www.bafang-e.com/en/products/motors/m-series/

 

[DaddyPaddey]

Would activating the walk mode help with that? It instantly powers the bike up to 2.5mph, only difference would be I'd be sitting on it.

Now thats a cunning plan,. Baldrick!

 

[DaddyPaddey]

Yes they do M series have some which are both torque and speed.

M600, M620, M815

https://www.bafang-e.com/en/products/motors/m-series/

What is the difference between them, would one suita fairly heavy recumbent trike better than the others?

 

[wiggydiggy]

Now thats a cunning plan,. Baldrick!

As cunning as a fox what used to be Professor of Cunning at Oxford University but has moved on and is now working for the U.N. at the High Commission of International Cunning Planning?

I'm quite proud of myself 😊

 

[DaddyPaddey]

What is the difference between them, would one suita fairly heavy recumbent trike better than the others?

Looking at their site the worry thing is I can't find any reference to myBBS0 2B motor being made, makes me wonder if its old generation