Out of curiosity I decided to take my Speed Passion v3.0 13.5 motor apart – it’s my first brushless motor and I was intrigued to see the differences to the old brushed motors.
The motor is held together by three long cap screws. Easy enough to remove. The next thing you notice is the incredible strength of the rotor magnet. You wonder whether it will pull half the motor out with it!
Exploded view of the SP v3.0 motor
Once disassembled you are left with the above. From left to right: endbell; sensor board; silicone seal; can with windings; rotor; faceplate; screws.
The endbell is made from aluminium and has holes for the three plugs and the sensor socket. Contrary to the markings on the endbell, the sensor socket can actually be moved a total of 20degrees, factory setting is in the middle at zero, rotating the sensor anti-clockwise advances the timing.
A little more on brushless motor timing. According to reliable sources, a “wye” wound motor (like this 13.5) will perform terribly at its true 0deg timing position – which is with the sensors in the middle of each winding. So, in practice, 30deg advance is treated as zero timing.
30deg timing is "zero" advance in a wye wound motor
Hopefully the image above shows this, albeit in a slightly blurry way! Looking down into the motor from the faceplate end, the red line marks the centre of the stator winding, the true odeg timing position. The green line marks the position of the sensor, 30deg advanced from zero. In this position, the sensor socket is in the factory “zero” setting.
Speed Passion v3.0 sensor board
Another view of the sensor board which has three sensors, one for each phase.
Speed Passion v3.0 13.5 rotor
Finally, the rotor. This is 12.3mm in diameter, and very strong. There is a small amount of balancing epoxy on it (hidden below the shaft) and also a couple of brass spacers.
The motor is hand-wound, ballraced and very fast. But best of all it is virtually maintenance free. Just blow away the dust and put a drop of oil on the bearings from time to time!
