Going Brushless Problems...

[momo5]

Hey guys. This is my first post. I've had my super cub for about 6 months and I feel I'm pretty good at flying it. I decided to upgrade it to brushless, and bought a little kit off of eBay. It came with a motor mount, turnigy 1100KV motor and mystery cloud 30a esc.

I'm having two problems.

One, the throttle. Initially I can throttle it up and the motor runs fine. But occasionally if I throttle all the way down, then throttle up..the motor doesn't spin. If I lower the throttle again, sometimes it starts working in 10 to 15 seconds...but then sometimes it doesn't.

Also the motor. Sometimes when I just barely hit the throttle the motor occasionally makes a crackling and popping sound, yet it doesn't do that if I give it a little more throttle or all the way.

I'm beginning to think this ESC is crap. I've read good reviews of the Turnigy 40a and think I'm gonna pull the trigger on it. I just wanted to see what you guys thought of this first.

[sham]

It does sound like the ESC, but without trying a known good one it's difficult to tell.

The fact they sell on eBay says a lot though.

[flydiver]

I think first you may have some high resistance in some wire, possibly a bad solder joint. Check all joints and wires carefully, that includes the motor. If you did the soldering and are new at it....well, triple check it, and maybe re-do it.
Just because it's 'new' doesn't mean it's good. These are cheap units with zero quality assurance, mostly true for pretty much everything you buy at bargain basement prices. It's 'the price you pay'.
It's not impossible that a magnet has come unglued in the motor. Again....cheap motors, no quality assurance.

You also may want to double check the throttle trim and calibrate the throtte-ESC:

[Throttle range setting: (Throttle range should be set each time when using a new transmitter or ESC).
Make sure the throttle trim is set to zero/neutral or below on the TX. The ESC will not arm if it detects positive throttle.

Switch on transmitter, move throttle stick to top.

Connect battery pack to ESC, and then wait for about 2 seconds and get a couple beeps.

Move throttle stick to bottom, wait for about 1 seconds

Arming beep tone should be emitted, means throttle range lowest point has been confirmed.

If none of that works, then you probably should try a new ESC.

Note-Some motors with high "cogging" (attraction of the iron core to the magnets making it turn by hand in a ratcheting way) may start hard with very low throttle as there is not enough energy to break the magnetic pull. Some ESC can be programmed from soft>hard start to help overcome this, or to make the start easier on some gearing systems like helicopters where you don't want an abrupt start.
You ___may___ be able to program it. Good luck finding instructions and actually accomplishing it. Stick programming sucks. Stick programming cheap ESC sucks toads. I don't buy any ESC anymore unless it is either PC or has a programming card. It doesn't seem like it but the ESC is the entire 'brains' of you motor and does a LOT of sophisticated stuff. Most folks don't have a clue how they really work.

Some folks seem to think cogging has something to do with power. Negative. You can tell almost nothing about a motor's power by the amount of cogging.

Recommendation - don't buy ANY RC stuff off eBay unless you ABSOLUTELY KNOW what you are buying. The chance of getting crap goes way up. Some of it is quite legit. Some is trash. If you can't tell, don't buy it.