Tempest 1708-2100 Performance Test Data
Magnets Motor Wind Motor Kv No-Load Current Motor Resistance I Max P Max (3S)
12-Pole 7-Turn Delta 2100 RPM/Volt Io = 0.68 Amps @ 10v Rm = 0.153 Ohms 13 Amps 145 W
 
Stator Outside Diameter Body Length Total Shaft Length Shaft Diameter Motor Weight
9-Slot 21.0 mm,  0.827 in. 19.5 mm,  0.768 in. 29.5 mm,  1.161 in. 2.00 mm,  0.079 in. 21.2 gm,   0.75 oz
 
Test Data From Input 6.0 V 8.0 V 10.0V 12.0V Measured Kv value Measured Rm Value
Sample Motor Io Value 0.530 A 0.604 A 0.679 A 0.812 A 2160 RPM/Volt @ 10v 0.1531 Ohms
 
2-cell Li-Po Test Data
Prop Prop Li-Po Input Motor Input Prop Pitch Speed Thrust  Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Watts RPM in MPH Grams Ounces Grams/W
APC 4.75x4.75-E 2 7.4 5.84 43.2 13,034 58.6 158 5.58 3.66
APC 4.75x5.5-E 2 7.4 6.52 48.2 12,666 66.0 145 5.13 3.02
APC 5x4.3-E 2 7.4 7.30 54.0 12,204 49.7 246 8.66 4.55
APC 5x4.5-E 2 7.4 7.41 54.9 12,147 51.8 242 8.54 4.41
APC 5x4.6-E 2 7.4 7.53 55.7 12,092 52.7 256 9.04 4.60
APC 5x5-E 2 7.4 6.62 49.0 12,554 59.4 158 5.57 3.23
APC 5.25x4.75-E 2 7.4 7.07 52.3 12,296 55.3 219 7.71 4.18
APC 5.25x6.25-E 2 7.4 8.91 65.9 11,257 66.6 190 6.70 2.88
APC 5.5x4.5-E 2 7.4 7.29 53.9 12,152 51.8 225 7.94 4.18
APC 6x4-E 2 7.4 7.94 58.7 11,809 44.7 279 9.85 4.76
APC 6x4.3-E 2 7.4 9.94 73.5 10,707 43.6 345 12.16 4.69
APC 6x4.5-E 2 7.4 9.77 72.3 10,777 45.9 349 12.32 4.83
APC 6x5.5-E 2 7.4 9.83 72.7 10,773 56.1 257 9.06 3.53
APC 6x6-E 2 7.4 9.96 73.7 10,674 60.6 284 10.02 3.86
APC 7x4-E 2 7.4 11.04 81.7 10,075 38.2 406 14.33 4.97
APC 7x4-SF 2 7.4 11.10 82.1 10,019 38.0 391 13.80 4.76
APC 7x5-E 2 7.4 12.32 91.2 9,218 43.6 369 13.03 4.05
APC 7x5-SF 2 7.4 12.13 89.7 9,366 44.3 386 13.63 4.31
APC 7x6-E 2 7.4 12.74 94.3 8,960 50.9 382 13.47 4.05
APC 7x6-SF 2 7.4 13.20 97.6 8,588 48.8 348 12.29 3.57
HQ 5x4.5-BN 2 7.4 7.48 55.3 12,081 51.5 265 9.36 4.80
HQ 5x4.5-C 2 7.4 4.92 36.4 13,552 57.8 215 7.58 5.91
HQ 6x3-C 2 7.4 4.75 35.2 13,649 38.8 233 8.23 6.64
HQ 6x4.5-BN 2 7.4 10.73 79.4 10,225 43.6 350 12.34 4.41
HQ 6x4.5-C 2 7.4 8.53 63.1 11,547 49.2 338 11.91 5.35
HQ 7x4.5-C 2 7.4 11.81 87.4 9,518 40.6 407 14.37 4.66
 
3-cell Li-Po Test Data
Prop Prop Li-Po Input Motor Input Prop Pitch Speed Thrust  Thrust Thrust Eff.
Manf. Size Cells Voltage Amps Watts RPM in MPH Grams Ounces Grams/W
APC 4.1x4.1-E 3 11.1 6.69 74.3 19,933 77.4 227 8.01 3.06
APC 4.5x4.1-E 3 11.1 8.16 90.5 19,068 74.0 293 10.33 3.23
APC 4.7x4.25-E 3 11.1 9.45 104.9 18,230 73.4 304 10.73 2.90
APC 4.75x4.75-E 3 11.1 10.35 114.9 17,658 79.4 290 10.23 2.52
APC 4.75x5.5-E 3 11.1 11.33 125.7 16,970 88.4 259 9.14 2.06
APC 5x4.3-E 3 11.1 12.22 135.6 16,329 66.5 438 15.46 3.23
APC 5x4.5-E 3 11.1 12.52 138.9 16,174 68.9 433 15.28 3.12
APC 5x4.6-E 3 11.1 12.58 139.7 16,010 69.7 453 15.97 3.24
APC 5x5-E 3 11.1 11.54 128.1 16,846 79.8 290 10.21 2.26
APC 5.5x4.5-E 3 11.1 12.64 140.3 16,061 68.4 396 13.95 2.82
APC 6x4-E 3 11.1 13.48 149.6 15,463 58.6 492 17.34 3.28
HQ 4x4-C 3 11.1 7.00 77.7 19,862 75.2 286 10.08 3.68
HQ 4x4.5-BN 3 11.1 8.85 98.2 18,691 79.6 330 11.65 3.36
HQ 4x4.5-C 3 11.1 4.74 52.6 21,245 90.5 208 7.35 3.96
HQ 5x3-C 3 11.1 6.98 77.5 19,913 56.6 311 10.97 4.01
HQ 5x4-C 3 11.1 8.39 93.2 18,922 71.7 412 14.52 4.42
HQ 5x4.5-BN 3 11.1 12.43 138.0 16,124 68.7 468 16.49 3.39
HQ 5x4.5-C 3 11.1 8.80 97.7 18,661 79.5 411 14.50 4.21
HQ 6x3-C 3 11.1 8.71 96.7 18,753 53.3 439 15.49 4.54
HQ 6x4.5-C 3 11.1 14.48 160.7 15,120 64.4 596 21.02 3.71
Propeller Chart Color Code Explanation
   The prop is to small to get good performance from the motor. (Less than 50% power)
   The prop is sized right to get good power from the motor. (50 to 80% power)
   The prop can be used, but full throttle should be kept to short bursts. (80 to 100% power)
   The prop is too big for the motor and should not be used. (Over 100% power)
PLEASE NOTE:
The Data contained in this Prop Chart is based on actual measurements, taken in a controlled test environment, at an altitude of
584 feet above sea level.  The test voltages used are based on the standard output of a Li-Po battery under load, which is 3.70 volts
per cell.  If you are using a battery that is larger in capacity than normal, or has a very high C-rating, then your actual voltages will
be higher than those shown in the chart, and this will result in a higher current and power value for every prop used.  You should
always test your actual power system with a watt meter before flying your model to make sure that you are not exceeding the 
recommended current and power ratings of the motor being used.  The prop recommendations in this chart assume that the motor
receives adequate cooling throughout its operation.  If your motor is being used inside a cowl or fuselage, you must ensure that
the motor receives sufficient airflow, and does not get too hot during operation.  It is always best to use a prop size that pulls no
more than 80% of the motors maximum recommended current value to ensure safe operation under all conditions.