Why is brushed a problem? What about brushless "fixes" it?

[rctoyguy]

I get that many brushed motors are overheating - but why? Is it from them having to turn too many RPMs, or from them having too much of a load to deal with due to the gear reduction? So, should I gear my brushed motor with a low pinion to ease some load on the motor and turn more RPMs, or do I go bigger pinion to turn less RPM but work the motor harder?

And what is it that brushless does that makes it work better?

It looks like I'll have to be brushed for a while, and I can't afford to try a bunch of different motor/pinion/esc combinations to hit on something that works reliably.

[davec]

[QUOTE=rctoyguy;1837320]And what is it that brushless does that makes it work better?[QUOTE]

Brushless motors tend to be more efficient, which results in less heat. Also, many of them have excellent low-end torque, which means they can pull a larger gear without working as hard. I am going to continue to run my 45t handwound for a while, then make a decision on the best brushless for the application.

[rctoyguy]

what brand motor are you running? what about esc, pinion, battery?

[davec]

I am running a Tekin FXR with a Tekin handwound 45t motor, 15t pinion, and a 3s 2200 Elite LiPo from cheapbatterypacks.com. Motor came off at about 150 degrees last time after about 15 minutes of running. Still warmer than I would like, but definitely workable for right now. Should get a little better as the axles and tranny break in more. My slipper started slipping last time out, so I need to pull the tranny apart and take a look.

[Robbob]

brushed - your operating it outside its comfort zone. to get the wheel speed your using more of its mid to top end. your using it more for the rpm but the torque of a motor fades the closer to its peak rpm you get it. (think real car dyno sheets and curves)

now the axles are geared low making us use those RPMs to get the thing moving, generating heat. then we come to a wall or obstacle and we try to climb over it. now we're trying to use the Torque of the motor to get the axles moving to climb it, by the time we get the wheels turning we have already gotten outside the torque range of the motor.

again generating heat.

my theory on why the Titan may be good right now is because its a longer armature, its a 550 motor. basically you have a longer arm able to take more wire helping produce the torque we need. same reason we say a 55T has more Torque then a 45, it has more wire around the poles.

now we take the Titan have more wire per pole but Less winds per pole, less winds brings more power. aka: why 35Ts are faster then 55Ts.

brushless can be more efficient then a brushed motor when they get hot, a brushed motor tends to drop in power when the magnets get hot, brushes tend to glaze over and comms can warp. next thing you have is a cloud of smoke and a paperweight.

brushless get hot too but remain consistent in performance, atleast untill they go poof.

im still in the same boat on gearing though and im a die hard brushed user, 15tooth seems about what most are saying so far but depends on motors.

good luck.

[1rcmonster]

Running a 35t integy, the cheap one, with a 14 tooth pinion. It gets warm but I would not say it is hot. The axles were broken in a shim removed and the trans was also broken in. I am thinking the more the truck is run the better everything will get.

[GhostRyder]

I'm surprised this is even an issue. I bought equipment based on research done on the Losi site. This article on the Losi site suggests a 55T motor is the way to "Properly Equip Your Losi 1/10-scale Comp Crawler"

http://www.losi.com/Articles/Article...ArticleID=1952

It's only after the release they turn around and say it won't work?

[2500hdon37s]

Originally Posted by GhostRyder

I'm surprised this is even an issue. I bought equipment based on research done on the Losi site. This article on the Losi site suggests a 55T motor is the way to "Properly Equip Your Losi 1/10-scale Comp Crawler"

http://www.losi.com/Articles/Article...ArticleID=1952

It's only after the release they turn around and say it won't work?

i am running a 55t and it just gets hot after a 10 minute run