Bafang brake sensor bypass

Garry Hallam

Pedelecer
May 18, 2024
49
4
Any info on bypassing the brake sensor cables on bafang 250w mid drive kit.

Are they really neccasary? I will not be fitting the throttle. My Decathlon of the shelf does not have them!



I am guessing it will be just a case of shorting pins on the connector.

Any info would be appreciated.
 
Last edited:

saneagle

Esteemed Pedelecer
Oct 10, 2010
5,158
2,494
Telford
Any info on bypassing the brake sensor cables on bafang 250w mid drive kit.

Are they really neccasary? I will not be fitting the throttle. My Decathlon of the shelf does not have them!



I am guessing it will be just a case of shorting pins on the connector.

Any info would be appreciated.
It's the opposite. Just disconnect them. They need to remain open circuit for the controller to give power. See how you get on without them. The motor might run on for a bit, which can be a bit annoying, though you can learn to live with it.
 

Garry Hallam

Pedelecer
May 18, 2024
49
4
It's the opposite. Just disconnect them. They need to remain open circuit for the controller to give power. See how you get on without them. The motor might run on for a bit, which can be a bit annoying, though you can learn to live with it.
Excellent. That's an easy fix. Less cables to get in the way too. I will see how it goes.
Thank you.
 

thelarkbox

Esteemed Pedelecer
Aug 23, 2023
857
259
oxon
You might find the brake motor cut off advantageous in a number of situations,
Im often slowly pedalling around obstacles and often people on the many local shared path/tracks when just cracking the brake lever to disengage the pedal assist is a great help as otherwise it would require turning off the battery or multiple button presses to step down through the pas levels to facilitate.
 

Az.

Esteemed Pedelecer
Apr 27, 2022
1,581
700
Plymouth
Why would you want to bypass brake sensors? It is very helpful safety feature.
Brake sensors will also prolong life of your motor.
 
  • Like
Reactions: Saracen

sjpt

Esteemed Pedelecer
Jun 8, 2018
3,730
2,693
Winchester
I have hydraulic brakes and the sensors will be difficult to fix on this bike.
Sensors for hydraulic brake levers are easy to fit. For example

Many more to choose from, and several yuoutube videos I've not looked at.

(We've got them because our brake and gear levers were integrated.)
 

Garry Hallam

Pedelecer
May 18, 2024
49
4
Sensors for hydraulic brake levers are easy to fit. For example

Many more to choose from, and several yuoutube videos I've not looked at.

(We've got them because our brake and gear levers were integrated.)
Yes, I fitted them to the last bike that I had. It was easy on that one as the geometry of the levers worked perfectly with the sensor placement.

This set of brake levers does not work well for fitment.

If I find that I really do want them in the future I will have to buy the Hyraulic levers like these

https://www.amazon.co.uk/PETSTIBLE-Brake-Electric-Bafang-Hydraulic/dp/B0D7MDPXGF/ref=mp_s_a_1_11?crid=4VFZ8PL8DCP9&dib=eyJ2IjoiMSJ9.Hyd1LvxrruZFFRCx8GAt01HHR35wAL0HoDIf1fBtBtcWyizQCK2x1BH1DDHwqozGPsTy_Jp38QacDtX7j7mW8c-bAvrVW4ARyPHJUe72COAdotdnKcNUMCEHR3c1LMZoCZ2gyxOyVY8kRYS-r_eHQI2Zsg9YOlTBTrwyP2rsPbyTw6TFVCbTVmpEdqkqUVl4Ce7S9AZXoHmu8TqeVin-aw.hOUB_I3Q8Msf08JPfk9sZc8yIygWTeMSJoFrgfJkxCY&dib_tag=se&keywords=bafang+hydraulic+brakes&qid=1720759880&sprefix=bafang+Hydraulic,aps,513&sr=8-11
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,461
8,346
61
West Sx RH
Brake sensors may be needed on systems with speed control or a bike that utlises a thottle, otherwsie they aren't pearticularly needed. At most one only needs one sensor operational on the rear brake.
When I had my BBS 01 I removed them as found them not necessary at all.
With my KT I simply don't need them.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,461
8,346
61
West Sx RH
You might find the brake motor cut off advantageous in a number of situations,
Im often slowly pedalling around obstacles and often people on the many local shared path/tracks when just cracking the brake lever to disengage the pedal assist is a great help as otherwise it would require turning off the battery or multiple button presses to step down through the pas levels to facilitate.
With a KT one wouldn't need them , the instances mentioned with a KT would not need sensors . KT has instant stop with no run on .
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
5,158
2,494
Telford
How would you determine if it is an instant stop or not?
If you remove one magnet from a 10 magnet pedal sensor, the power cuts every time the missing magnet passes the sensor, so you can say that the power definitely cuts within 20% or 72 deg of a pedal rotation at around 60 rpm, so that would be within 0.2 seconds maximum, and probably less.
 

Az.

Esteemed Pedelecer
Apr 27, 2022
1,581
700
Plymouth
If you remove one magnet from a 10 magnet pedal sensor, the power cuts every time the missing magnet passes the sensor, so you can say that the power definitely cuts within 20% or 72 deg of a pedal rotation at around 60 rpm, so that would be within 0.2 seconds maximum, and probably less.
...so removing 5 magnets should give on/off impression of 50%/50%...
0.2 seconds is not to bad. TSDZ8 unfortunately doesn't stop immediately.
 

Voltsnamps

Pedelecer
Aug 27, 2023
54
7
TSDZ8 unfortunately doesn't stop immediately.
Thanks for that Az, first time I’ve read that, totally unacceptable, of course, torque sensitive must stop immediately, that’s part of the attraction, guess we have to wait till we can play with settings. Took me a while to get Baf pas to not run on, all good now but Bosch I’m riding today is perfect (but for riding through treacle over 15mph).
Run on is lethal off road, not nice in traffic
 

vantage

Finding my (electric) wheels
Jun 25, 2022
21
1
I disconnected then chopped the brake sensor cables so there weren't any dangly wires flapping about.
I've tweaked the motors settings so it stops running the second I stop pedalling. I find that in some circumstances, I can use the motor on rocky uphills yet still use the brake to control the motors power if it runs away from me.
I found out that using the brake sensor in the same situation sometimes lead to a complete loss of power and so lack of forward momentum thus leading to a close up view of the ground.
 

Saracen

Esteemed Pedelecer
Aug 24, 2023
496
52
And the reason is???

If you know about e bikes, motors and motors you wouldn't ask

Read 10

.
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
5,158
2,494
Telford
If you know about e bikes, motors and motors you wouldn't ask

Read 10

.
Yes I do. That's why I don't have brake sensors on any of my bikes. That's why I'd like to know your reason. Did you try without them?