Could someone explain brushless / Lipos etc

[daz75]

Coming from the old school of brushed / nicads, all this brushless stuff is confusing me

I used to run 10x2 in my Losi XX, i'm guessing there isn't really an equivalent these days, but i'm guessing the lower the number the faster it is, but what i dont get it why some low turn motors are massively cheaper than others, e.g. on this page
http://www.jemodels.com/index.php?ap...rushlessMotors

Also, what's sensorless and sensored all about?

On the Lipo front, i can see different amounts of cells, i assume this is the 1S 2S etc, what's usually used in lets say a Losi 22?

Also, whats the C rating, seems to be about charge and discharge rates, and higher seems more expensive, which i assume means better, but am unsure what it's all about.

Sorry for the probably dumb questions

[racingdwarf]

hi

6.5 or 7.5 is in my opinion about 10x2 ish these days, but in 2wd 7.5 is normally as quick as you want before things start to get a bit of a handful.

I have never used a sensor less motor but the ones I have seen don't seam to run anywhere near as smoothly as the sensored motor

Yes the lower the number the faster or more punchy the motor is, in off road we tend not to stray any lower than 5.5 in 4wd but the touring car guys love speed and can to stray lower I have read, as I've never got involved with them. I'm not sure why they are cheeper maybe just amount sold less popular just don't know but don't be drawn to a 4.5 in your 2wd

Lipo's 2cell hard case is what you want, now days shorty type lipos seem to be more and more popular in 2wd and 4wd set up's. altho saddles are also good for both types. I'm not a authority on C but yes C is discharge rate the higher the C the higher the, discharge rate, in 2wd you can use quite a low C rate but in 4wd with a 5.5 bolted in on astro you want to be looking a the higher C ratings.

1 cell is for use in 12th mostly and you need a 1 cell esc or use a booster.

[Rob]

Regarding lipo's have a read of this

http://www.rchelicopterfun.com/rc-lipo-batteries.html

[daz75]

thanks guys, still not sure about this sensor/sensorless stuff, what's it a sensor for?

[Col]

It tells the speedo where the motor is (in it's rotation) so it can apply power accordingly.
Motors and speedo's without sensors tend to "stutter", particularly from standstill while the motor gets to the correct position in it's cycle in relation to what the esc is giving it.
I have never had, and never will have a sensorless motor. Nor should any other serious racer. IMO.

[Essex2Visuvesi]

Originally Posted by Col

It tells the speedo where the motor is (in it's rotation) so it can apply power accordingly.
Motors and speedo's without sensors tend to "stutter", particularly from standstill while the motor gets to the correct position in it's cycle in relation to what the esc is giving it.
I have never had, and never will have a sensorless motor. Nor should any other serious racer. IMO.

It's strange its only RC car motors that use sensored technology..... most boats, planes and helis all use sensorless motors
My son ran a Sensorless motor in his TC over the summer and placed second in his class.
Granted they do cog a little on power up or at low speeds, but in race conditions when do you run slowly?

[Col]

True, all my quadcopter motors are sensorless, but the only time they are ever at zero throttle is when they crash
Sensorless are better than they used to be, but (IMO) are simply not as good as sensored.

(second in class means nothing - there could only have been 2 people racing , or maybe he's just naturally tallented in a field of 50 )

[dazp83]

My 1/8 (team orion esc) is unsensored and has no cogging but when I started in 1/10 i had a cheap unsensored in that and sometimes it would cog very badly.
Would recommend sensored in all and next 1/8 esc I'll buy will be sensored.

[mattr]

In buggies, a badly set up (or rubbishy) sensorless motor *can* be all but undriveable. Especially in the twisties, or when you have low traction.

Sensored is just one less thing to worry about.

[Essex2Visuvesi]

Originally Posted by mattr

In buggies, a badly set up (or rubbishy) sensorless motor *can* be all but undriveable. Especially in the twisties, or when you have low traction.

Sensored is just one less thing to worry about.

Then again a badly setup sensored can be just as bad

[mattr]

You'd have to try really hard to get it that bad.
And it'd be a doddle to fix.

And it'd be a completely different set of issues too.