Target Headspeed Calculator

	Lipo  A123
Battery Pack:	One cell (1S) - 3.7 v Two cell (2S) - 7.4 v Three cell (3S) - 11.1 v Four cell (4S) - 14.8 v Five cell (5S) - 18.5 v Six cell (6S) - 22.2 v Seven cell (7S) - 25.9 v Eight cell (8S) - 29.6 v Nine cell (9S) - 33.3 v Ten cell (10S) - 37 v Eleven cell (11S) - 40.7 v Twelve cell (12S) - 44.4 v Thirteen cell (13S) - 48.1 v Fourteen cell (14S) - 51.8 v	One cell (1S) - 3.3 v Two cell (2S) - 6.6 v Three cell (3S) - 9.9 v Four cell (4S) - 13.2 v Five cell (5S) - 16.5 v Six cell (6S) - 19.8 v Seven cell (7S) - 23.1 v Eight cell (8S) - 26.4 v Nine cell (9S) - 29.7 v Ten cell (10S) - 33 v Eleven cell (11S) - 36.3 v Twelve cell (12S) - 39.6 v Thirteen cell (13S) - 42.9 v Fourteen cell (14S) - 46.2 v
Main Gear Teeth:
Motor Pinion:	7 Teeth 8 Teeth 9 Teeth 10 Teeth 11 Teeth 12 Teeth 13 Teeth 14 Teeth 15 Teeth 16 Teeth 17 Teeth 18 Teeth 19 Teeth 20 Teeth 21 Teeth 22 Teeth 23 Teeth 24 Teeth 25 Teeth 26 Teeth 27 Teeth 28 Teeth 29 Teeth 30 Teeth
Motor Kv:
1 Efficiency:	75 % 76 % 77 % 78 % 79 % 80 % 81 % 82 % 83 % 84 % 85 % 86 % 87 % 88 % 89 % 90 % 91 % 92 % 93 % 94 % 95 % 96 % 97 % 98 % 99 % 100 %
Head Speed:
Motor RPM:
2 Gear Ratio:	: 1

---

Pinion Gear Calculator

	Lipo  A123
Battery Pack:	One cell (1S) - 3.7 v Two cell (2S) - 7.4 v Three cell (3S) - 11.1 v Four cell (4S) - 14.8 v Five cell (5S) - 18.5 v Six cell (6S) - 22.2 v Seven cell (7S) - 25.9 v Eight cell (8S) - 29.6 v Nine cell (9S) - 33.3 v Ten cell (10S) - 37 v Eleven cell (11S) - 40.7 v Twelve cell (12S) - 44.4 v Thirteen cell (13S) - 48.1 v Fourteen cell (14S) - 51.8 v	One cell (1S) - 3.3 v Two cell (2S) - 6.6 v Three cell (3S) - 9.9 v Four cell (4S) - 13.2 v Five cell (5S) - 16.5 v Six cell (6S) - 19.8 v Seven cell (7S) - 23.1 v Eight cell (8S) - 26.4 v Nine cell (9S) - 29.7 v Ten cell (10S) - 33 v Eleven cell (11S) - 36.3 v Twelve cell (12S) - 39.6 v Thirteen cell (13S) - 42.9 v Fourteen cell (14S) - 46.2 v
Main Gear Teeth:
Target Head Speed:
Motor Kv:
1 Efficiency:	75 % 76 % 77 % 78 % 79 % 80 % 81 % 82 % 83 % 84 % 85 % 86 % 87 % 88 % 89 % 90 % 91 % 92 % 93 % 94 % 95 % 96 % 97 % 98 % 99 % 100 %
Pinion Gear Teeth:
Motor RPM:
2 Gear Ratio:	: 1

Main Gear Reference
Align TREX 450	150
Align TREX 600 (Straight Cut)	170
Align TREX 600 (Helical)	188
Raptor Mini Titan	150
Raptor E550/E620	111
Mikado Logo 10/14	200/138
Mikado Logo 500/600 (Herringbone)	212/153
Hirobo Lepton	94
XCell Razor 600E	90

Note: Calculators are intended to provide estimates only. Some motor/esc combinations are more or less efficient. Final headspeed should always be checked with a tachometer.

¹ Selecting an efficency of 95% is usually more accurate on modern power setups.
² It is not recommended to use a gear ratio lower than 9:1 to ensure proper torque and prevent high cuurent draw.

Courtesy of