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BrianG · 10:16 AM

Yeah, but it's usually not that much in practicality. High kv motors, having fewer turns, have less resistance. So, current is higher, but resistance is lower. There are more losses to be sure, but it's not that much.

Take a monster truck; judging by the average runtimes people get, the average power required is around 300w.

Let's say we are using a 1515/1y (kv 2200) on 4s. With that 300w average power figure, the average current is around 20A. Losses are around 2.4w, which is 0.8%.

Same vehicle and average power, but with the 1515/2.5d (kv 1650) on 6s will have an average current around 13.5A. Losses would be around 1.8w, which is 0.6%.

See? Not really enough to consider IMO. Yeah, bursts currents/power will be higher, but those are short in duration. Even so, the percentage of losses will be in about the same proportion.

But we aren't really talking about high kv/low V vs low kv/high V comparisons really. The question seems to be: Given a specific voltage, what is better; high kv geared down or low kv geared up. But really, the end is the same.

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BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	04.13.2009, 10:14 AM Yeah, but it's usually not that much in practicality. High kv motors, having fewer turns, have less resistance. So, current is higher, but resistance is lower. There are more losses to be sure, but it's not that much. Take a monster truck; judging by the average runtimes people get, the average power required is around 300w. Let's say we are using a 1515/1y (kv 2200) on 4s. With that 300w average power figure, the average current is around 20A. Losses are around 2.4w, which is 0.8%. Same vehicle and average power, but with the 1515/2.5d (kv 1650) on 6s will have an average current around 13.5A. Losses would be around 1.8w, which is 0.6%. See? Not really enough to consider IMO. Yeah, bursts currents/power will be higher, but those are short in duration. Even so, the percentage of losses will be in about the same proportion. But we aren't really talking about high kv/low V vs low kv/high V comparisons really. The question seems to be: Given a specific voltage, what is better; high kv geared down or low kv geared up. But really, the end is the same. Last edited by BrianG; 04.13.2009 at 10:16 AM.