BHT Engine

                                              From endless-sphere.com/forums topic.
bht-bdlc-48V1000WBig block GNG style, single speed / single reduction rear drive motor, 12magnets,  48V1000W-60V1200W.  50mm long x 80mm diameter rotor, small lams, big phases to boot and 120mm inner case diameter. Max speed around 60kp/h, max hill climb gain of 30.6% or 17° for 40A battery and 100A phase current. It will output 28Nm of torque at the shaft at 100A Phase current. BHT engine was used in first LMX bikes.
single_speed_big_block_aternativeIn this 4:1 geared configuration it should behave like a geared hub drive with 8.7KV. So equal to a BMC V1 (it has about the same weight and 8.4KV geared in the ebikes.ca simulator). A BMC V1 has more magnets and more reduction, but I guess it has less copper. So this single speed config should behave the same in the simulator, except it will barely overheat :) Above is a graph for 72V & 40A of the BMC V1.
single_speed_big_block_aternative2Compare BMC V1 and this GNG big block alternative geared 4:1 @48V, both at 270rpm. They have about the same KV, the big block alternative has 60Nm. The BMC V1 has 45Nm. Specs: KV: 34.7 rpm/V (derived from graph), KV: 32.9 rpm/V (measured with multimeter), Kt: 0.275 Nm/A, Inductance: 311µH @ 400Hz with 1m cable.
HIGH-RES_big_block_alternative_Magnets: 12. Laminations: 0.5mm ? Hall sensor placement: 120°. No load Consumption: 1.20A @ 45V. 1.46A @ 80.6V (this differs for different controllers). Winding Terminaison: Star / WYE. Weight: 5.32 kg / 11.7 lbs. Bearings: 6203 RS.  Some no load consumption measurements i did after soldering cables to the star ends: 46.2V Delta: 134W 2589 rpm, 46.3V Star: 75 W 1500 rpm, 79.2V Delta: 340 W 4440 rpm (this sounds nice 8) ), 79.7V Star 135 W 2582 rpm. Max rpm with acceptable eddy current loss (250Hz / 0.5mm Lams): 2500rpm. It seems like this motor is perfectly suited for 72 and 96V systems in Star/WYE (Stock) or 48V in Delta (mod).
2017-08-01 17.11.45This motor used on the GNG style mid drives is derived from mass-produced, really cheap, rickshaw motors, used on manual shift multi-speed rear axles for trikes. They are available in many lengths but diameter seems to be quite constant, even if it seems there are different pole counts. With 26″ Wheel and 80Nm at the wheel you can make wheelies on most bikes. At 120Nm, most bikes wheely so much you can’t stand it. With 10T/66T reduction it will give you stupid amounts of torque… top speed should be around 40km/h. Build index:  dirtydrumbzhwindtalkerwhiplash. >>> VIDEO <<<
single speed builtMore info :
Phase resistance______________________0.7 Ohm (cheap multimeter)
4 holes BCD__________________________135mm diagonal
Extrusion width_______________________80mm
Overall width_________________________140mm
Case width___________________________110mm
Axle diameter________________________~14mm (need to find my vernier callipers)
Base feet holes center to center_________145mm
Base holes size________________________22*10mm
Base holes from side of the extrusion_____4mm
Winding Terminaison___________________Delta
Lamination thickness___________________0.5, really hard to tell.
KONICA MINOLTA DIGITAL CAMERALhe LMX P1 is very similar, different tensioners need to be tested. If chain growth is too much, it will need 2 idlers like in a rear derailleur, (better to avoid that). This is a v-brake chain tensioner, nice idea since the torsion spring is already built-in.
100mmWill it fit a 100mm BB? It is 110mm, under the screw heads it’s ~96mm.  Since 110mm is the outer dimension incl. covers that include the bearings, it tells me that this will definitely fit a 100mm BB, a nice option for sandbikes.fix-motor-midDrive-bhtlargebig_block_14T_54T_24inch_calcThis setup will be absolutly brutal. With 3.3kW you can reach reach 70kph, simple math tells you that for 100 you need almost exactly double of that. The 60kph are only a “guess”, in real live it will be a bit faster, maybe 65kph. Made for offroad. I just tried 100V on that motor to see what it says to it: Does rpm rise linearly up to 100V? Yes it does. Need a 18Fet Infineon controller. This motor is wound so slow that it only does around 15k e-rpm even at 100V. Even the slow Sabvoton controllers should work fine with these motors. Seems incredible –  this 8 x 11 cm small box can do 130A phase current!

7000w
top power >> 7000W

bht1bhtbht grupsetBHT21200w72Vbafang-pieces-1024x739triplechaindoublechainyy with BT601602srgolden

IMG_36051234
www.gngebike.com/gng-belt-kit

gng2

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