Ebike derestrictor

soundwave

Esteemed Pedelecer
May 23, 2015
16,463
6,365
 

khblue

Just Joined
Mar 27, 2021
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0
I think the specifics of the magnet winding must be a key element to making this work.

A relay winding has about 150 ohm resistance and so will draw about 80mAmps from a 12 volt battery. But A23 12volt batteries only provide about 15mAmps peak. The 3volt battery in the BadAss wouldn't produce anything like enough Field Strength in a standard relay winding, so something else is going on. Either that or the Giant Entour (Yamaha) uses a much higher field strength than other bikes.
 

aegidius

Finding my (electric) wheels
Mar 13, 2023
7
0
et me know if you need any of the 3d files. I'll be uploading them to thingiverse soon and ill post the link there when im done
Any progress on the upload? I looked in Thingiverse and found you, but no mention of Ebikes. Curious to see how you placed the magnet relative to the sensor. I'm looking at a similar solution using a Nano to do the units+decimal display that some of the dongles do.
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
5,163
2,498
Telford
That derestrictor is relatively expensive and pretty complicated for what it does. You can achieve the same result with a double flipflop as a frequency divider that doesn't need any code.

The problem is that neither method of deristriction works on most bikes now. I tested some, and I found that all they do is show a lower speed on the display. The controllers that I tested picked up the speed signal for restriction from the motor hall sensors, not from the speed sensor.

If you're unsure about whether your controller can be tricked, you can test it by using one of these to put any fixed speed signal into the controller rather than the one from the speed sensor:

If it shows that your controller does use the speed sensor as the signal for the restriction, you can leave it in place as a derestrictor, though you'll get a constant speed shown on your LCD of whatever you set it to. You have to turn it right down to get it into the ebike working range of about 50 to 300 hz before you see a speed on the LCD, and, of course,.you won't get any power to the motor until you have it set below 15.5 mph, which is around 200hz.

The wiring is dead simple. Splice into the motor cable and take a branch off the red for 5v, black for ground, and cut the white wire so that the controller side white wire is connected to the device. You can use a motor cable extension that has a male and female motor connector on each end if you don't want to cut your bike's cable, then you can wire in and out the test device or restrictor as you please.
 
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aegidius

Finding my (electric) wheels
Mar 13, 2023
7
0
I have been trying to find out how the Bosch antituning SW works, and the best guess I have is that it accumulates the number of pulses from the wheel sensor over a ride, and compares that with what it expects (within some broad limits) given the power output, motor RPM, cadence and input torque from the pedals. The motor has no idea of what the gear ratio to the wheels (afaik) so it cannot be accurate but can trap really silly values.

If you have a tuning chip there will be fewer pulses sent to the motor than are generated by the wheel magnet, and if this deficit gets too high, the motor will log an error.

This jibes up with the story told by tuning chip makers, that you have to leave the bike on for 60 sec. at the end of the ride, while the chip puts back those "missing" pulses. You can see the speedo flashing during the cooldown period in this short video:
which is what you expect if pulses are being squirted in while the pedals are not turning and the motor is not running (like a little downhill run at the end of the ride).

Any thoughts? Neither Bosch nor the tuning chip makers will talk on this, but am I on the right track here?
 

soundwave

Esteemed Pedelecer
May 23, 2015
16,463
6,365
the kiox display on my bike records everything speed mileage elevation even with no phone connected and then it also has gps for maps.

now b4 i did a software update the kiox display did not do this as had the app on my phone but after the update it now sends it all to the app on the phone just if i dont take my phone with me it has no gps.

i dont have a smart motor but speed and mileage is half on my bike so 10 miles is really 20.

if they start using gps to real time track the bikes then no dongles will work.
 

Lukas1

Just Joined
Mar 2, 2023
1
0
What inductor parameters to use? Because now I'm using 10mh, Hall sensor doesn't react at all
 

aegidius

Finding my (electric) wheels
Mar 13, 2023
7
0
The controllers that I tested picked up the speed signal for restriction from the motor hall sensors, not from the speed sensor.
This could work for hub motors, but it won't be the case for mid drives, as they don't know the gear ratio.
 

aegidius

Finding my (electric) wheels
Mar 13, 2023
7
0
I have been trying to find out how the Bosch antituning SW works, and the best guess I have is that it accumulates the number of pulses from the wheel sensor over a ride, and compares that with what it expects (within some broad limits) given the power output, motor RPM, cadence and input torque from the pedals.
Does anyone know if the Gen4 motor board has an accelerometer? If it does, it could tell between hill climbing and flat ground, narrowing the range of its expectation...
 

papzo

Just Joined
Aug 30, 2023
2
0
This is a circuit that works well for me. I tried the external coil/relay first, but it was taking too much power plus bulky. It is on bosch performance line 2015 which uses reed switch instead of hall sensor.
Hi there! I have the same Bosch system, can we get a components list please?
 

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