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Old 09-09-2008, 04:56 PM   #1
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Questions?? here's a riddle for you

ok, I have a GM racing V3R esc rated for 18t at 6 cell, I can run a 19t reedy spec(flame lable) with an 8 cell pack, the esc gets to about 130*, and the motor gets to 160*
hot, but not too hot, obviosly the esc is under rated.

today I wanted more torque, so I put a 27t monster stock motor in it and ran it with 6 cells because my 8 cell was charging, the esc stayed around 100* but the motor fryed itsellf at 400*+ I checked the trany for any binding and found non got one of my other monster stock motors and tryed it again, makeing sure that the mesh was set right and that it rolled smoth, I stoped that motor from frying at 200* after 3 min. of runing.

whats happaning??????

this is a stampede with the stock sper and 22 tooth pinion both times
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Old 09-09-2008, 04:58 PM   #2
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sounds overgeared......
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Old 09-09-2008, 05:37 PM   #3
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I was thinking that to, but why would a 27t overheat and a 19t not?

I have more pinions on the way
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Old 09-09-2008, 10:44 PM   #4
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First, are you properly meshing the gears?

The gears cannot be mashed together. You have to leave an ever so slight gap between it. I usually feed a strip a paper between the spur and pinion and squeeze. Then tighten the motor, then back the paper out. The thickness of the paper should give you a perfect mesh between the two gears.

Second, torque and rpm doesn't necessarily oppose each other as the winding of a motor goes up and down. Remember that heating in a motor is through power dissipation. Motors draw the most current when it is stalled. As loading increase on the motor shaft, the condition is going towards a stalled shaft. Off-loading the motor for load can be achieved by increasing the gear ratio. Assuming that you have no binding and your mesh is correct, all signs point to over gearing...
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Old 09-09-2008, 11:02 PM   #5
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The peak pinion threshold is higher with the 19t because its got bearings. The stock is over loaded with not only the gear but the bushing. Poof.
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Old 09-10-2008, 10:50 AM   #6
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that makes sense, except that I chaned the bushings to bearings in one of them. IDK, it dosn't realy matter, I was just wondering what happend

besideds, a 19t in a stampede with a 8 cell is FUN
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Old 09-10-2008, 11:57 AM   #7
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Electric motors don't like to be stalled. When they're moving slowly or not at all, they're essentially a dead-short. A 27T in a stampede just won't have the "beans" (power) to move the truck easily...a 19T with 8 cells will have the power.

Bog it down and it gets hot. If it's overheating that badly, you need to use a LOT smaller pinion.
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