I`m sorry for doubting your ability to use a multi meter, and now i am the amateur...
""in full power 2 seconds of pedling and wattage goes straight up to well over 1200w"" this suggest to me that the settings in the display unit may not be adjustable or not adjusted correctly, please keep in mind that i have been known to be wrong on several occasions however i`m still not afraid to admit it.
Here is a brief explanation of the display parameters, your parameters may differ some by not having all the options included.
If you like check your configuration vs this guide and see if it helps any.
Always write down all the parameters that are present before changing them.
I forgot where i got this from but it helped me out a lot when i was making my first steps treble shooting my new configuration, thanks go to the original poster.
Look at your P07 P09 P10 P11 P12 P13 .....
Press UP + DOWN
buttons to enter configuration menu. Parameter PXX, beginning with P01, will show on screen in the SPEED
section. Parameter value will show in the bottom right of the display, in the ODO
buttons to change value of parameter.
Short press M
button to select next parameter.
Long press M
button to save current parameter.
When in configuration menu, press UP + DOWN
to save parameters and exit configuration menu.
After 10 seconds of inactivity, configuration will automatically be saved and exited.
P01 Backlight Brightness
1-3, Higher is brighter.
Brightness of the display in low light (night).
P02 Unit of Measurement
0 for Kilometers, 1 for Miles
Sets the displayed unit of measurement for odometer and speed.
P03 Battery/Controller Voltage
Sets battery voltage. This should match the output of your battery. Used to calibrate battery level indicator.
P04 Inactivity Timeout
0-60 minutes, 0 disables inactivity timeout.
Automatically sets display/controller to sleep after a given time of inactivity.
P05 PAS Levels
0 or 1
0 = 3 Levels, 1 = 5 Levels
Sets of the number of Pedal Assist System (PAS) levels available. More levels = finer control over amount of assistance given by the motor.
P06 Wheel Size
Diameter In Inches, Precision 0.1
Sets the wheel size of the bicycle in inches. Correct wheel size is required for accurate speed and odometer function.
P07 Motor Speed Magnet Type
Set to 47 for direct drive motor, 86 for geared motor
P08 Speed Limiter
0-100 km/h, 100 for unlimited
Shuts off motor when using PAS and above set speed limit. This parameter's value is always in km/h, so a mph limit must first be converted to km/h first!
P09 Throttle Response
0 for instant throttle, 1 for delayed throttle
Sets whether pressing throttle and motor beginning to spin is instant, or whether there is a delay between the actions.
P10 Throttle Mode
0 = PAS Only, 1 = Throttle Only, 2 = Both PAS and Throttle
Sets which sensors are used for throttle control.
P11 PAS Sensitivity
1-24, Higher = more sensitive
Sets how sensitive PAS is to movement of the pedals.
P12 PAS Start Strength
0-5, Higher = more assistance
Amount of assistance given when you start pedalling.
P13 PAS Magnet Type
5, 8, 12. Determined by magnets (dots) on PAS ring.
Sets PAS ring magnet type as determined by the number of magnets on the ring.
P14 Controller Current Limit
1-20 Amps, some versions of sw900/controller allow higher values.
Sets the current (amp) limit of your controller. Setting this value to something higher than your controller or motor can handle may cause damage!
P15 Not Implemented
This parameter is unused
P16 Odometer (ODO) Reset
Press and hold UP
button for 5 seconds to reset ODO counter to zero. Some versions of SW900 do not contain this parameter.
P17 Motor Wattage/Display Option
Some versions of SW900 use this parameter to switch between displaying battery voltage and wattage.
Sets the wattage of the motor. Some versions of SW900 do not contain this parameter.
Here is another video walk thru the settings: