In which case there’s good news for you, just cracked the Phub-188 open!
I figured the two end caps likely attach to the rotor with those screws in them, and hold the rotor in place with bearings. After removing the screws nothing would budge, but a solution presented itself in the form of a hammer.
By furiously hammering at the non-wire side of the axle I got the stator and the other endcap to slide out somewhat, I could then grab the endcap and pull the stator out with it. Really snug fit between the bearing and the axle.
Tight magnet packing, no retaining rings or anything extra to keep them in place. Also no O-ring between the endcap and rotor, so this motor is not waterproof.
There is an O-ring on the axle which is nice. The hall board is held in place only by the sensor leads and some blobs of putty, but seems to be pretty solid and the sensors themselves are embedded in the laminations.
There’s some knotted string holding the magnet wire in place, and some wooden dowel-things used to wedge it tight in the slots. The magnet wire is wrapped in some sort of insulation in the slots, which I guess would reduce the chance of it rubbing and breaking on the edges.
There’s a fair bit of empty space between the stator and the endcaps on both sides, moreso here where the wires come out. Assuming Peipei’s power specifications actually mean anything, it could be that they simply make the stator with different lengths. There’s certainly room to grow for the “800W” version which is now on Aliexpress.
A zip-tie holds the phase wires in their place.
Someone with more knowledge of motors could say whether this winding is good or bad. It does seem to fill the slots pretty nicely, but there’s the odd strand which is more loose than the others. Handmade?
This here looks like it might be the wye center termination. It’s got three sets of wires going in there. Can someone with more experience with this sort of thing confirm? Appears to have 6 parallel wires in each set of 3, so 6 parallel wires per “turn”?
I guess this is where I’d need to do my work if I’m to convert it to delta, breaking out that center connection and soldering each set of three to the (hopefully) right phase wire.