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supraracer
06-25-2009, 02:02 PM
Ok well i recently installed a mamba micro pro 8000kv set-up in my mini-t with a 11.1v lipo and im not sure whats wrong but the first day i ran it, it was very quick ( not as fast as i think it should be never had a problem with wheelies or anything) But the last 2 runs i did with a fully charged battery it is very slow and will stop and go when it pleases.
This is my first brushless car so i could use any advice.
Also it is pulling left, camber is as close to 0 as i can get (free play in the parts i cant seem to get it straight up) Can i adjust that on my Tx? Im pretty new to all of rc.

thanks for the advice
-wildman

cowboysir03
06-25-2009, 06:38 PM
The stopping and starting and slow pace sounds like the Mamba knows you've reached your voltage cutoff...are you sure it was fully charged when you had those two runs? (i hope you've used the cell pack I mailed to you since you've received it and this isn't your first go around....)

As for initial speed and wheelies, you may want to read your Mamba setup instructions and find out where the default settings are placed. Sometimes it may be a default setting of low timing and start speed to keep you from the wheelie thing.

Pulling left from a standstill or while you're moving? If it's from standstill it may be the differential releasing power to the rear wheels unevenly but if it's moving when it happens it may be a steering trim issue.;)

skylinedriver
06-25-2009, 08:40 PM
I'm running the same set up in my RC18T. First, make sure that your li-po is a good quality pack. Brushless require a lot of amperage to get started...1500mAH or higher capacity, rated at 25C or higher discharge rate. Next check that the cut off limit is set at either auto cut off(which is what I use) or 9 volts/cell. Do not use the default which is no cut off, this will allow you to discharge the pack below the limit of 3.0 volts/cell. If this happens the pack is trashed. Also check that the punch control is not set to high, and that the start power is set to low. Some of this settings cannot be changed by "stick programming" and can only be accessed by the Castle Link programmer.
The starting and stopping could be caused by many things...loose/bad connection, interference between the motor and the receiver(brusheless give off their own radio frequency which normal). Try to seperate the two as much as possible. Check for any binding(i.e driveline, pinion/spur gear mesh)
Mine used to pull to the right. I fixed that by tightening up any slop on the servo saver and A arms and other suspension components. That's all I can think of right now. Check those things and I'm sure someone else will chime in. We'll help you get this figured out buddy. :thumrigh:

supraracer
06-25-2009, 09:14 PM
well i seem to have most of the pull out ( seems one of my turnbuckle screws came loose and left lots of room for steering slop)

Also i think i may have figured out why it might be slow and cutting out, if this could cause it. My brother was fiddling with it and touch the positive and negative terminal on the battery, with the use of the charger cable, and he said it got really hot( bottom of the battery) Im assuming he fried the cell causing the battery pack to be trashed?

I also checked over my esc settings using the castle link and yes it set to low power up until 70% throttle.
so im guessing the problem is the battery (dang kids) let me know if this is possible and yes it is the pack i got from you Cowboy

skylinedriver
06-25-2009, 09:42 PM
That will definitely cause an issue. You need a new pack. If the pack got hot because of a short or overcharge/dicharge then stop using the pack and find a recycling center that accepts lipo. Some hobby shops have recycling boxes.

cowboysir03
06-26-2009, 12:29 AM
Also i think i may have figured out why it might be slow and cutting out, if this could cause it. My brother was fiddling with it and touch the positive and negative terminal on the battery, with the use of the charger cable, and he said it got really hot( bottom of the battery) Im assuming he fried the cell causing the battery pack to be trashed?

so im guessing the problem is the battery (dang kids) let me know if this is possible and yes it is the pack i got from you Cowboy

Your brother is lucky he didn't start a chemical fire.:eyecraz:

I'd get a voltage tester on it and check if the pack seems misshapen since you last used/received it...you sometimes get swelling with bad treatment of li-po's so you may have a visual indicator that something is wrong.

Tough break man....:(

supraracer
06-26-2009, 01:44 PM
Im so ****ed, hes deffinitly getting a beating. Its not even the money although i did get a great deal on that pack its tough even finding a 11.1 volt pack that fits.

i guess this means its back to working on the brushed car.

skylinedriver
06-27-2009, 09:22 AM
I suggest a Maxamps pack. They are a bit pricey, but well worth their weight in gold. I have one and love it. Here's the link. http://www.maxamps.com/proddetail.php?prod=Lipo-1550-111-Pack&cat=144

supraracer
06-27-2009, 09:40 PM
yes but that pack does not fit in a mini-t.

skylinedriver
06-27-2009, 10:51 PM
DOH!!! Sorry wasn't paying attention. How 'bout this one. http://www.maxamps.com/proddetail.php?prod=Lipo-1100-111-Pack&cat=156

supraracer
06-28-2009, 08:09 AM
Thats perfect size, ill be picking on of those up soon. I thought i looked at there site i must have missed this one. Thanks for the help i appreciate it.