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Old Apr 18, 2012, 04:07 AM
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did you try and charge on storage mode then today tried it on balance charge.
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Old Apr 18, 2012, 06:44 PM
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did you try and charge on storage mode then today tried it on balance charge.
I'm pretty sure it wasnt storage mode...it was the normal lipo charge...2nd time was a balance charge.

EDIT: Im charging it now again and I drove it earlier for like almost 10 minutes before the over heating kicked in...i was gentle on the throttle this time. I also ordered a 2s pack.
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Old Apr 19, 2012, 05:04 AM
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Is there a device or something that I can purchase that will attach between the motor and the esc and perform as a volt limiter? Limit how much voltage the motor pulls from the esc? Whole purpose of this is to prevent the esc from overheating.

Also could it be because its a 4wd? Is there a chance the.esc won't overheat if I run it in a. 2wd?
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Old Apr 19, 2012, 06:08 AM
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More of a weight issue than 2wd v 4wd, but it is a factor.
I think your combo is for >3-4lbs vehicle. I'm not 100% sure on that but it's what i'd say
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Old Apr 19, 2012, 07:30 AM
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It's the gearing, drivetrain drag and weight combined, the new truck weighs too much and has too much drag in the driveline for the gearing you're trying to run. If you run a smaller pinion it will be fine, or a milder motor.

The stock motor is very low RPM and high torque, you replaced it with a higher rpm motor with less torque, but running the same gearing.

There's no way to limit voltage getting to the motor, but if you adjust the gearing or get a milder motor you can limit the amp draw. It's current that heats up the parts, not voltage.
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Old Apr 19, 2012, 01:43 PM
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Ok well this happens in the Hpi rs4 too with everything stock not only the truck. So when I buy a pininon do I only replace the one that goes on the motor or also the one That sits inside the car? The big gear? Also which one should I get? I don't want to lose a lot of performance or torque. Just enough to keep the esc cool..also what ia a bec?
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Old Apr 19, 2012, 04:57 PM
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BEC = battery eliminator circuit, it supplies power to the RX from the main power pack. ESC's have them built in usually, but you can buy separate ones as well.

For the gear, just the pinion (the one on the motor). You don't really have much choice unless you upgrade to a heavier duty ESC or run less voltage. Dropping to a 2s pack will lower current (and heat) by quite a lot without changing anything else.
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Old Apr 20, 2012, 05:15 PM
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It's the gearing, drivetrain drag and weight combined, the new truck weighs too much and has too much drag in the driveline for the gearing you're trying to run. If you run a smaller pinion it will be fine, or a milder motor.

The stock motor is very low RPM and high torque, you replaced it with a higher rpm motor with less torque, but running the same gearing.

There's no way to limit voltage getting to the motor, but if you adjust the gearing or get a milder motor you can limit the amp draw. It's current that heats up the parts, not voltage.
The stock pinion gear is a 22T with a 48 pitch. I just picked up 2 pinion gears from a local hobby store, a 19T and a 24T. Salesman didnt understand my question and thought i wanted more torque so he suggested a 19T. When I confirm with him if its the right product I need and realized he's thinking the opposite I got thrown off myself lol, so i bought a lower and a higher.

I'm pretty sure I use the 24T correct? And it will decrease the torque and increase the top speed??? right?
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Old Apr 20, 2012, 06:01 PM
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The stock pinion gear is a 22T with a 48 pitch. I just picked up 2 pinion gears from a local hobby store, a 19T and a 24T. Salesman didnt understand my question and thought i wanted more torque so he suggested a 19T. When I confirm with him if its the right product I need and realized he's thinking the opposite I got thrown off myself lol, so i bought a lower and a higher.

I'm pretty sure I use the 24T correct? And it will decrease the torque and increase the top speed??? right?
I have also tried this setup in the traxxas rustler roller that I picked up a few days back and it still over heats but not as much. The clipper clutch in the rustler might also be helping a little with heat dispensing. I think the stock spur gear on the rustler is 72T.

Now I'm thinking I should have bought a 25+ pinion gear... might go replace it.
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Old Apr 20, 2012, 06:39 PM
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No, you're thinking backwards... to reduce heat you need to run a smaller pinion gear. If you run a bigger pinion gear you will increase amp draw and heat. If stock is 22T and you're having severe over heating issues, you might have to go as low as 17T.

When you increase voltage you have to run a smaller pinion, and the motor/esc you have were designed for 7.2v, not 12v.
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Old Apr 20, 2012, 07:54 PM
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No, you're thinking backwards... to reduce heat you need to run a smaller pinion gear. If you run a bigger pinion gear you will increase amp draw and heat. If stock is 22T and you're having severe over heating issues, you might have to go as low as 17T.

When you increase voltage you have to run a smaller pinion, and the motor/esc you have were designed for 7.2v, not 12v.
Yea I figured lol. I called them earlier and found out the samething. So running a smaller pinion will give the car more torque or less? Cause I thought it will give it more torque thus causing it to over-heat. Bigger pinion will reduce the torque and increase top speed so the motor can reach its peak rpm without struggling?

So if I'm understanding this right what im getting out of it is small pinion might put more pressure on the motor but it will slow down amp draw to take stress off the ESC.

Sorry for being such a noob lol.
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Old Apr 20, 2012, 08:37 PM
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The gear doesn't effect how much power the motor can put out, but it does change how much load is put on the motor.

A small pinion gives the motor more leverage over the wheels, which increases torque output to the wheels while decreasing load on the motor, decreasing current draw and decreasing heat.

A bigger pinion gives less leverage reducing the torque output to the wheels, increasing load on the motor, increasing current draw and increasing heat.

Think of it like a bicycle... a smaller sprocket up front makes it easier to pedal, while the bigger one makes it harder to pedal, but increases your speed if you have the power to push it.
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Old Apr 21, 2012, 05:59 AM
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i don't think you could gear it that low for it to work any good.
The motor would suit a 1/18 car.
When you bought the motor, what was it used in before hand?.
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Old Apr 21, 2012, 02:37 PM
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i don't think you could gear it that low for it to work any good.
The motor would suit a 1/18 car.
When you bought the motor, what was it used in before hand?.
Its too big to fit in a 1/18. It came out of the Hpi rs4. I haven't tried it with the 19t pinion.

I'm picking up a reedy 3300kv brushless system later in today from a local guy...running with a 3s I might need a stronger spur gear.
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Old Apr 21, 2012, 03:49 PM
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sorry that was supposed to be 1/12
the motor has a max lipo of 2s though.
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