Back in 2010, Liveforphysics made a thread asking if anyone had one of the hubmotors made for the Avanti Electra. Here's the original thread:
https://endless-sphere.com/forums/viewto ... =2&t=22255
Apparently about 1000 of them were made and sold around the year 2006. The actual motor development was done by a company called IMT Motors from the Northern Territories which had a background in motor development for solar car racing.
The complete bikes looked pretty ordinary:
Fast forward to today and I've got one which came with a blown controller and a bit of a wobble in the rim. Although I don't have any immediate need for an ebike with an 8kg front wheel, this motor has so many interesting design characteristics compared to most conventional hubmotors, I thought it would be fun to play around with.
First, here's photos of the wheel from both sides:
Some items of note externally:
* the silver right side (drive side) rotates while the entire black left side is stationary
* attaches to the bike fork with a quick release skewer
* one long bolt on the stator appears to connect to the bicycle's fork to act as torque arm
* drive side spokes radiate 2 cross from near the centre of the hub
* non-drive side spokes connect at the hub's perimeter and are also 2 cross but banded in pairs with stainless rings
Here's some internal photos from the thread I linked to above, showing magnets (rotor) and the windings (stator):
Anyone know how many pole pairs the motor has? I count 16 magnets and 48 stator slots. Normally I would have thought 16 magnets means 8 pole-pairs but with so many stator teeth in the axial-flux design I'm not so sure.
I plan to fool around with the motor first using the GrinTech ASI FOC controller which can do both sensored and sensorless control.