NEED INFO: High kV + Low Voltage 'vs' Low kV + High Voltage?

[Chadworkz]

I think the main reason to go with a low kV motor and a high voltage battery is efficiency, right? If so, what other reasons and/or benefits are there? If I am wrong, which is better, and why?

Thanks in advance!

[zoojunkie]

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Can't read it?

Clogging and low speed resolution. You'll get clogging and very poor low speed resolution w/ a high kV brushless.

[Grizzly4x4]

A low KV motor will have more bottom end torque to get the rig moving.
A high KV motor will do as illustrated above and cog really bad at startup and while crawling at low speeds.

[NeXt559]

clogging? i thought it the term was cogging
X2 for chadworks

w/ crawling and brushless look for low kv brushless motors that is unless your willing to invest in a some hefty priced batteries that can handle an uber amount of amp draw to start up smoothly

[floogldood]

There will be less current as well (if the power is kept the same)

[shierkahn]

I am about to be going BL, does that mean the lower kv the better? Or is there a limit on how low for crawling? what would be the lowest you would go with 11.1 or 7.4, 1550mAh 2 or 3s, 20c lipo? thanks for the help

[cartronicshn]

Also sensored brushless inrunners have the smoothest start up of all bl motors so far, JRH is working on some sensored outrunners also.
I have outrunners on a 3 of my rigs, not so smooth start up and when bound up cogging does happen, and i also own 3 novak goat systems on 3 other rigs, definetly smooth and low end and mid range torque on these novak systems.
Kv i think should be around 900-1100 or somewhere along these lines if i remember correctly, although you have to take in account gearing, esc amperage and volt handling and finally batt specs.

[Chadworkz]

Thanks for all the help, but I really meant in general, like for regular bashing and racing vehicles....not crawlers. I know this is a crawling forum, but I trust what you guys know and say when it comes to anything related to R/C.

So, in terms of powerful and fast non-crawlers, which combo is better...and why?

[Espeefan]

Non-crawling applications are a whole 'nother ball game. If speed is your need, then motor choice is based mostly on 'how fast do you want to go?' Gearing will also play a large roll in the selection. You definitely need to choose your speed controller and batteries, based on the motor selection. Current draw becomes the main concern. The more voltage you run, the higher the current draw becomes as well.

Your original statement is correct. A lower KV motor is more efficient then a higher KV motor. Higher KV motors get current hungry in a hurry. A lower KV motor running, on more cells, is likely to be a little more gentle when it comes to continous current draws, then a high KV motor on the same number of cells. A lower KV motor is more like a torque motor, so while it spins less RPMs, it can be geared higher (numerically lower), without as much concern to overheating.

[Chadworkz]

Sweet, exactly what I wanted to know, thanks a ton!