thingi

https://learn.sparkfun.com/tutorials/how-to-use-an-oscilloscope/all https://circuitdigest.com/microcontroller-projects/arduino-waveform-generator https://www.hackspace.org.uk/ = advice & probably some help + access to stuff you don't have already or want to buy (google hackspace + your closest city if none on the list are close to you, the list is far from complete).

Yup, indeed the sensor connector does look like a small hub cable connector, it's also possible to sniff the sensor readings / send fake readings to the battery / controller via a Raspberry Pie Zero or Arduino to de-restrict and/or make push button powered any of the GTech ebikes (it's bollocks that they aren't moddable). I've not done mine yet... but the PoC worked.

There is no need to change the sensor, just the v2 battery holder (and it's bracket, two separate items BOTH are required for the swap). then it's just a simple matter of connecting the new holder to the current cable at the crank (there's a hole in the bottom of the frame for this purpose, it's dead simple).

The Battery holder + Bracket are dead simple swap out. Just inside the frame near the bottom bracket there's a standard (nine pin DIN?) connector plus a single lead for the pedal sensor (which is also inside the bottom bracket) the other cable leads to the motor. Don't be afraid of them, on the new battery holder there's another nine pin din connector so it is a simple swap out and cable ties are all that's needed (that rubbery epoxy stuff comes off real simple, not scary at all). Sent you a pm in case you just want a v1 battery instead. Since you do need a new charger to go v2 - luckily I already had one from my v2 battery mtb that I have as well as the city model.

Gtech don't do any bike support anymore. It's was all done via cycle republic Sole distributor. They did sell v2 and v1 cages and batteries (its a lottery which one you'll get even when they order the correct part - sigh). You need both the new v2 bracket and also the new v2 battery holder. Bracket needed as well as the v2 battery holder - the battery retention clip is different on each. On your v1 frame only one screw hole is in the right place for the v2 holder but it's not an issue and is not over strained. I have two v1 batteries (Both in surprisingly good health + v1 holder I could let go of...

There are known issues with a batch of v2 batteries, for a while they were difficult to buy from cycle republic (sole distributor), they may still be... The local shop order bits and what comes in isn't what was ordered. Great front-end service, shit back-end service. They have many complaints, it's only one batch of bad batch of v2 batteries, inside knowledge, but not nice if it's you. However, I now have two v.1 (with four led display) from my 2nd hand really old (but mint) Gtech. A v2 that came with my Gtech mtb + a 2nd battery that was difficult to order. I bought a v2 battery holder for my v1 e-bike so I can now swap batteries between the e-bike + mtb version. The problem with the v1's was a poorly designed retention mech, it's easy to break the handle on the battery and four leds were fairly difficult to see in daylight, but the batteries themselves are really solid. The v2's led screen display is easier to see and gives a fair reading of battery left but it doesn't drop linearly. The first few % are burned through very quickly, this gives a good idea of the battery health. Both types like to be treated properly (or at least fairly). The only real way to do that it is to have a second battery. Keep the first charged up and always use the maximum of the battery before swapping to the 2nd. Just don't expect the rated range. after a while, it does go down, but not anymore than I'd expect out of a really good laptop battery over time, but its over generous to start with especially in 'High' all the time Real usage on hills is more like half that if you ride it lazily, you know pedal to the whole time at a certain cadence that kicks the power out the most with the least effort If your battery is acting weird it all depends upon where you bought your bike, Gtech or Cycle Republic. Good luck if it's Cycle Republic, you probably need it. If its Gtech ask for a replacement if it's acting like that. The working product is basically totally solid, some shit happened to some of them, that may be you