Gearing!!!! HELP!

[OGMUDBONE]

Just bought a new 35t crawler motor from RC4WD. Its there new BOOST motor and not going to lie it runs pretty good. My only qustion was I noticed the motor got pretty warm for just testing it out inside my house before heading out. AM I running the right gearing? I have a 20t pinion and the stock plastic spur gear. Or is it just normal for motors to get hot? This is my first crawler so I am new to crawling.

[TrickyRicky]

What crawler do you have? 2S, 3S,nimh batt? what size tires? do have wieght in the tires? Any binding in the drive train? I use 18 pinion and 91 spur with 1.9 ttc claws with 3S and 2oz in each front tire does your moter have adj. timing? I use 0 deg. in all my crawler moters

[indiana mudcat]

Hot means geared high, drop pinion teeth. Try a 14 or so.

[OGMUDBONE]

Im running a 2s lipo with 1.9 proline tires and homemade wheel weights but they arent anything too heavy that it should cause the motor to overwork itself. No binding on the tranny or driveshafts or gears Tricky Ricky. I dont know much about timing and have never played with the motor or any of that stuff. RC4WD said it should be set from the factory I guess since its made to plug and play. Thanks Indiana mudcat. Ill try a 14 pinion gear and see how that goes. Will that give me more torque???

[OGMUDBONE]

The truck is an axial SCX10 BTW sorry leaving that out.

[SMR 510RR]

20t should be fine, I have one set up almost identical to yours. How hot are we talking here? Can you hold you finger on the can for a couple seconds without having to pull it off?

[OGMUDBONE]

it gets warm where I can touch it without it burning my finger. Is that normal??

[OGMUDBONE]

Yes the motor gets warm, but I can touch it no problem and it doesnt burn me

[MotoMudder]

no problem. If it gets too hot to touch, then you have issues.
But cooler is better.

[AddictedtoRC1]

I would suggest around a 5.5:1 gear ratio. It will keep the motor at a safe temp. Volt up, gear down. In other words run a 3S if you can and a smaller pinion. If you get into a trail run at any point where it's constant half to full throttle that's when you'll see a problem with motor temps at your current gearing. I run a 16t pinion with stock spur on a 35T powered by 3S and it works great. No heat issues at all.

[OGMUDBONE]

thanks for the info. I noticed today when doing some really full throttle crawling that the motor started to smoke and was really hot and I mean hot. This was running with the stock spur gear and 20t pinion gear. Ill gear down the pinion gear and go from there? wish me luck

[Tonysmini]

Chances are if it's smoked then you've knackered it and may need a new one.

[dna4engr]

Originally Posted by OGMUDBONE

thanks for the info. I noticed today when doing some really full throttle crawling that the motor started to smoke and was really hot and I mean hot. This was running with the stock spur gear and 20t pinion gear. Ill gear down the pinion gear and go from there? wish me luck

Mudbone
Someone above mentioned it and it really sounds like the timing is too advanced on the motor. I don't know much about the rc4wd motors. Most have little tick marks close to the end bell where the wires attach. Timing is changed by loosening the screws on this end bell and rotating it relative to the can. Advancing the timing makes the motor faster but run hotter. I've ruined a 21t venom motor the same way. So hot it melted the solder of the wires.

You should contact rc4wd customer service and ask for a replacement. A 35t motor running on 2ccell with 1.9 tires should never run warm really. Especially since you're running a 20t pinion with I assume an 87t spur. That's 4.35 gear ratio. I have an older kyosho 22t motor in one of my scx10s running wraith gearing at 4:1 (20 t pinion/ 80t spur). My motor gets warm to the touch after crawling but never hot running on 2cell lipo and turning 1.9 Mickey Thompson ttc bajas.

One more thing to look at is where your motor wire connections are relative to the suspension link mounts on the frame. Scx10 ark ways have the link mount closest to the motor endbell really close to the motor leads. Maybe it's grounding to the frame???

The only other thing I can think of is if you've been running in thick muddy clay. Then the motor will get hot really fast. Or if you have gotten the tires in a big bind on the rocks and powered your way out.

Good luck with rc4wd

[AddictedtoRC1]

Originally Posted by dna4engr

Mudbone
Advancing the timing makes the motor faster but run hotter. I've ruined a 21t venom motor the same way. So hot it melted the solder of the wires.

While I agree that advance timing can have adverse effects on a motor, a motor would have to be advanced quite a bit to fry itself. I highly doubt the RC4WD motor came with advancement far enough to ruin it. It likely didn't come with any advancement. So unless Mudbone changed it I highly doubt that is what fried the motor.

[Crawler149]

How heavy is your rig?