THE Cub Report, 04.12.2015, Version- Understanding Brushless
Last week one of my minions working in the industry shot me a link to a new “blog”. In that particular blog, the writer talked a whole lot about brushless power systems, but mainly about BL motors. Post after post talked about things like how to rebuild a brushless motor, how to service a brushless motor, how to upgrade the internals in a brushless motor, basically, how to do a whole lot of work and spend a whole lot of money on a brushless motor. Obviously, the writer of said blog had No Flip’n Idea what brushless power is all about, nor do a whole lot of other people in our hobby. From local racers to sanctioning bodies, some people just don’t “get” what BL is all about. Thankfully they have me here to explain it to them.
So exactly what was the promise of brushless power systems? A few things-
1. More power
2. To be more efficient
3. To require less maintenance
And btw yes, BL has delivered wonderfully on all three accounts.
Do they put out more power? OMG, if you are a noob and never drove old school 27 turn stock motors, or even 6 turn hand wound mods, yes, brushless puts out a lot more power. No doubt, a good hand wound 6 turn brushed motor put out a lot of power, but even the best of the best would pale in comparison to a good BL 540 on 4S. Oh and, a 6 turn brushed had the life expectancy of a Mayfly, a good BL will last for years.
Are they more efficient? Wanna compare run times between an old 12 turn brushed motor and a modern 3300kV brushless motor? Absolutely, run times are insane now days, partly thanks to the extra efficiency that BL motors have to offer.
Do BL motor require less maintenance? Absolutely. Provided you don’t over-gear and cook the motor to death, I have BL motors with a ton of hours on them that are a decade old and they run as good today as the day I bought them (with the only maintenance being a drop of oil on the bearings every once in a great long while). Once again for the noobs, I don’t much care what type of brushed motor you run, they need a lot of TLC to keep operating correctly. Heck, I know racers (a lot of them) that spent more time rebuilding and tuning brushed motors than they spend watching their kids grow up. Sad, but true. Even more sad, I know guys that spent so much time tuning/rebuilding motors that they never even had families. If you are “working” a lot on BL motors, you are doing it wrong.
Unfortunately, too many people don’t use brushless the way it was intended. For example, power. The race crowd uses 21.5 to 13.5 brushless motors to pretend to have some form of stock/noob class. Brushless motors are for putting out a LOT of power, not for pretending to go slow. If people truly understood brushless, those wanna-be “stock” classes would not exist. Wanna go fast? Go brushless. Wanna go slow or have a noob class? Use brushed. Try to go slow with BL and all you end up with is a lot of people burning up motors for no good reason. What sense is there in that?
Some people have no idea how to use the additional efficiency. For example, at several of my local tracks the race lengths are still the standard 5 minutes. We’ve been using 5 minutes since the Earth cooled. We have all this extra runtime available, yet the racing crowd never wants to use it.
But… the biggest gripe I have is how the people that don’t truly understand brushless feel like brushless motors need to be tinkered with- to be rebuilt all the time and to be “tuned”. A good, proper BL system shouldn’t need constant tear-downs. It doesn’t need its rotor changed out to alter its “powerband”, that can and should be done electronically. Nor does a proper BL motor “need” a different rotor for more power. A proper BL system should have wayyyyy more than enough power for most normal applications. For instance, why change out a 17.5 rotor for more torque when the driver really should be using a much more powerful motor on a higher cell count? If the driver feels the need to go slow, popping in a Mabuchi 540 is quick and easy (and really, Really, Slow).
To boil it down- if you raise your hand and want to run brushless, then run it properly, if you want to go slow and constantly fiddle with your motors, freak’n hello, go back to brushed.
That’s it ya punks, support your local hobby shops and bash spots when ya can.
YOUR Cub Reporter