cogging and efficency
 

could someone tell me which brushless motor/esc setup will provide the greatest efficency with the least possible cogging?
the cogging issue is kinda scaring me. i don't exactly understand what cogging is really so could someone post a vid or send me a link to a vid that demonstrates typical cogging and how it affects the overall experinece in using brushless

thanks

RE: cogging and efficency
 

Cogging happens with sensorless brushless systems. Basically, when accelerating from a stop the speed control can "lose track" of where the motor's rotor is. This leads to stuttering as the ESC tries to figure out which position the rotor is in. A sensored setup, on the other hand, has basically no cogging because the sensors can tell the ESC exactly what position the rotor is at.

So if you really want to eliminate cogging, get a sensored brushless system like one of the Novaks or the Reedy setup. However, some sensorless setups are very smooth. For example, I've heard that the Mtroniks Pro ESC (which is for sensorless motors) is very smooth.

As far as efficiency goes, all brushless motors are efficient compared to their brushed counterparts. I don't know specifically which motors are more efficient, though my Novak SS5800 gives me great run times.

RE: cogging and efficency
 

typical [peak] motor efficiency:

brushed low turn [6-12t] motors: 50-60%
brushed spec brushed motors: 60-70%
brushed stock motors: about 68-70%
brushed powertool hi-voltage hi-efficiency motors: 70-80%

brushless sensorless esc&motor combo: 75-80%
brushless sensored esc&motor combo: 80-90%

sensored combos do not 'waste' power during un-needed stator windings ring current flow. they 'fire' the winding that should be fired by an angle of 90degrees towards the coresponding rotor pole. therefore, providing maximum efficiency. multi-pole motors also contribute to efficiency increase. more poles = more efficiency, but more complex design and higher price as well. a 3pole motor compared to a 5pole one will have as much as 5% less efficiency.

RE: cogging and efficency
 

don`t be afraid of cogging. unless you will be rock-crawling [max throttle sensitivity at low-speeds required], you won`t have a problem. SS pede did a good job on explaining what cogging is.

RE: cogging and efficency
 

one more quick question, i hear about glitching with novaks alot and i run the stock fm radio will this be a huge problem?
does hte sphere/neo combo have less glitching than the novak?

glitiching kinda scares me, i dont know what to expect from the glithving?

thanks

RE: cogging and efficency
 

it is said that the neo/sphere creates less radio interference. however, with the FM radio, you most likely will not experience any glitching with any of those setups...