Thanks everyone!
I ordered both of them from EBW after seeing them recommended on Reddit. These look similar to the Bolton kits ,but I have NO idea if they are the same. Though I did find it interesting that both incorporated brake lights around the same time...
I've seen power peak at 1400W at the display, and it sustains 600W, so I'm _guessing_ it's the same as the US 750W?
https://electrobikeworld.com/products/35a-controller-rad https://electrobikeworld.com/products/kt-lcd3-with-usb-radI was worried that I would lose the tail light control (I had read that the 35A didn't support it without splicing cables) but this revision of the controller does support it.
It's a good size, larger than the OEM controller:
After pulling the wiring harness out, it was easy to see what went where, no two plugs are the same, and they're all designed to only connect one way.
The hardest part was fishing the display cable out of the frame (despiste reading numerous warnings to be Very Careful when removing it).
You can see I've wrapped tape around the connection in case I need to get the cable out again.
I clipped off the tie holding the motor cable in place.
The skid plate makes a handy mounting plate, I did have to cut a notch out of the tab at the front so everything lined up.
I gathered the cables back up, running the display and front brake cables along the downtube, and folding and squeezing the rest of the cables under the gap between the Vee of the rear arms and the battery case.
Display bolts on easily enough, it's nice and clear, and green!
When setting the display & controller, I used these values. I use 24" as the tyre diameter, (the total diameter including the tyre)and metric settings.
I used the following P & C settings. Mr. Bolton's excellent guide is a great explainer of what each does:
https://www.youtube.com/watch?v=B0F6x8V0NZQ& Listing them here for my reference, use at your own risk, E&OE, values may fall as well as rise, if you continue to experience symptoms after 14 days, seek professional advice.
https://880b28d3d003e6b1c176-ee9159906b823979ce618332e73bec87.ssl.cf4.rackcdn.com/other/en_KT-LCD3.pdfP1 - 100 (this is standard for a Bafang motor with 20 magnets, and a controller with 5 PAS levels, 20*5=100)
P2 - 5 (pulse settings for calibrating speedo, this took trial and error)
P3 - 1 (full power assistance from throttle, regardless of PAS level. 0 gives a relative ramp up in assistance, depends on PAS level selected) .
P4 - 1 (pedals must be moving before throttle twist gives power. Setting to 0 allows throttle regardless of pedal or PAS level)
P5 - 15 (battery bar calibration. Set to 00: bars indicate instantaneous voltage (these flutter a lot depending on power draw) or use a higher value for smarter metering. (12 for 24V batteries, 15 for 36 & 48V batteries. This controller is not suitable for 52V packs afaik)
C1 - 3 (Pedal assist sensitivity, other values may work here)
C2 - 0 (Sine wave phase settings, you can leave this at zero for a Bafang 750W motor)
C3 - 8 (Power level on startup, 0-5 or 8 to remember what you left it as when you switched it off)
C4 - 1 (0: All the throttle, all the time 1: throttle to 6kph only without pedalling, for EU compliance. 2: Throttle up to a level you can set (MXS Speed flashes to set this) The rest of these are in the PDF linked.
C5 - 10 (Max power limit 10= 100%. 9 = 90%, 8 = 80% etc. )
C6 - 5 (backlight, 5 is max brightness)
C7 - 1 (Cruise Control, 0 is off, 1 is on)
C8 - 0 (1: Display motor temp. This only works if your motor has a temp sensor. Mine doesn't)
C9 - 0 (1: enable a PIN)
C10 - n (Reset to default settings)
C11 - 0 (protocol mode for communitcating with USB programmer)
C12 - 4 (Minimum battery cutoff: 40V. Refer to the PDF linked)
C13 - 0 (Regeneration level - not supported by my geared motor, left it at 0)
C14 - 3 (special sauce. PAS fine tuning. default is 2, 3 is mo powah, baby. Expect range to tumble)