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Jumping, but not in a good way.

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Old 10-21-2009, 10:45 AM
  #1
jenius8477
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Default Jumping, but not in a good way.

Ok, I am new to crawling in rc scale ( i have previously built a 1:1 crawler for superlifts rock comp). I have a Redcat Racing Super Crawler and when i try to use a 7-cell pack it jumps. its like the esc is seeing it as a 12 cell that is too low to run. any ideas?
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Old 10-21-2009, 11:21 AM
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Default RE: Jumping, but not in a good way.

What do you mean by "it jumps"? What battery, esc and motor are you using?
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Old 10-22-2009, 08:18 AM
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Default RE: Jumping, but not in a good way.

Well i am using the stock electronics. Twin 100turn motors and a 3300mah nimh. but the jumping only occurs when i use my 2s lipo or my 7cell nimh.
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Old 10-22-2009, 12:34 PM
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Default RE: Jumping, but not in a good way.

Jumping? Twitching? They could be caused by electrical noise if you don't have any capacitors installed on the motors. It seems strange to me that two different batteries, like the 3300mah and the 2 cell LiPo have different effects on the truck. With the 3300 everything is fine, but with the LiPo the truck jumps? [sm=50_50.gif]

Is your transmitter range normal?

It could be the ESC. With increased voltage maybe it is sending intermittent signals to the motors.

Could the motors be arching with the higher voltage?

Reset everything and keep your fingers crossed. Solder three capacitors on each motor. Shield the motor wire connections with heat shrink tube. Start trying to eliminate components by trying another ESC, another receiver etc.

I wish I could help, but I'm just guessing. []
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Old 10-22-2009, 03:58 PM
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Default RE: Jumping, but not in a good way.

i think that because the esc sees the increased voltage and thinks its a high voltage pack that is just dead cause when my other packs go dead, the jumping occurs but less powerful.
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Old 10-22-2009, 09:59 PM
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Default RE: Jumping, but not in a good way.

just a few pics after a few mods
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Old 10-22-2009, 11:17 PM
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Default RE: Jumping, but not in a good way.

Looks good! [sm=thumbs_up.gif]
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Old 10-22-2009, 11:18 PM
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Default RE: Jumping, but not in a good way.

tomorrow at work im gonna be trimming down the monster bumpers into something more manageable lol
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Old 10-23-2009, 01:58 PM
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Default RE: Jumping, but not in a good way.

after my mods to the bumpers and greasing of the trannys.
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