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Some Australian states (not sure which ones but Qld where I live does) have legislated that motorists must give 1 metre separation (1.5m if 80km/h). I have never had any problems on the road, most drivers are patient if they need to wait to pass safely.

@Hamina how did you get on? Did you ever find those sockets? I'm still trying to hunt them down but no luck. An extender for the speed sensor cable (with plug one end and socket at the other) would be just the thing I'm after.

Just because they have a patent doesn't mean they will do it, or even intend to. It could be just to stop other people doing it (or to throw derestrictor makers off the scent!)

Bosch have a patent on this method, so they either do it now or could do in the future. I've tabulated the gear ratios in a spreadsheet and worked out good values for multipliers. The gear steps are not always exactly the same (since tooth counts are confined to integers) but they come out...

I would imagine that the new motor would work with any Bosch battery, otherwise battery swaps would be too complex - but it may have to be paired with the display (Purion etc). You may be able to get around this by buying a new motor along with its display. (I'm thinking of getting a NZ spec CX...

I doubt that this is true - regardless of how fast or slow you pedal the relationship between cadence and speed will fall into a fixed set of gear ratios (assuming the wheel circumference and cogs do not change). The patent talks about measuring the sharpness of the peaks and looking for...

There is also the possibility that the new SW is looking at the values of its measured gear ratio (which changes with multiplier) and seeing that they are not fitting into a previously gathered histogram of gear ratios, as per that Bosch patent I've been banging on about. Might be a red herring...

Come and do some lobbying in Australia. Please. Someone tried to get up a petition here to bring in a class following the EU s-pedelecs (45km/h) and got nowhere. We follow the EU regs for 20km/h ebikes just to allow importation and sale. Even a small change to allow the NZ speed would be a huge...

Feels reasonable to me that they would check the on-time of the sensor, it's very simple for them to do. They would need to ignore situations where the wheel just stops on the magnet by luck, but that's a zero to low speed situation.

There's a Bosch patent that talks about it. The motor samples cadence and wheel speed at regular intervals, divides one by the other to get a gear ratio, and forms a histogram of these gear ratios. Over time there should be sharp peaks corresponding to the physical ratios. If too many readings...

Agree. yes it is inaccurate at slow speeds, since they only measure once per revolution... but there will be a timeout value, if that is exceeded then you are trackstanding at best (and falling over at worst). They also (per their patent) can detect which gear you are in, so there will be an...

Rotation of the pedals, with torque, cannot occur when the wheel appears stationary. The motor would throw a wheel sensor error, as it would think the sensor had failed.

Mine is the spoke magnet and wired sensor version (Gen 4 CX non-Smart), so I don't know if it even has the pickup inside the motor casing.

There are two-wire Hall sensors (not VR). See here for an example. I can't prove it but the Bosch spoke magnet sensor appears to use this or a similar one. From the motor it sinks ~1mA when the magnet is present, otherwise it's open circuit. It can be reliably read by an Arduino pin with a...

The difficulty with my cunning plan is that there are so few spare Bosch motors with blown/bricked PCB's or otherwise available for parting out. As a first step, I'd like to see a good clear pic of both sides of the PCB, in order to identify chips. I know there's a Gen 3 teardown out there but...

Have been thinking the same lines myself. The Bosch geartrain is great, and the power electronics are good too. We don't need to re-invent those. What might be a good line of inquiry is to identify the signals going to the motor controller (3-phase bridge) chip, and the raw signals coming from...

Agree. What the histogram method could detect is an arbitrary mapping between input speed and output speed - like a sort of nonlinear speed-dependent gear-ratio. One of the commercial ones (Volspeed, speedbox?) does a smart-system derestrictor that maps speed 1:1 up to 22km/h, then divides by 10...

Bosch have a patent (mentioned upthread) that covers detection of gear ratios in use, but collecting data points on cadence and wheel speed (as measured by sensor) and making a histogram. The resulting histogram will have well-defined sharp peaks corresponding to the gear ratios. From this they...

That is interesting, in light of some comments I've seen that the Bosch displays and batteries are keyed to the motor and need dealer SW intervention to make them work together. It opens the door a bit to motor swaps. Good too that the algorithm of changing the multiplier over a very short time...

One way to check if it's a reed or a hall, is to see if it triggers with both poles of the magnet. The hall chips only work with one pole (like the south pole in the case of the TMAG5124). Or else just listen for the clicks :-)