Power/controler problems

We have a problem with bruiser 2, as it has very little power, we have a 5:1 reduction on the cheap eBay speed 900 like motors, but they stall a lot, on start up and turning etc, and then on top of that, the 2 25amp syren controlers we have controlling it just cut out when we try to turn or drive, it can just about drive forward if we bank it up slowly, but it would be very impractical for combat, so I was wondering what we could do, would adding the two spare motors onto it help, and what higher current controlers could we use? We were looking at the sabertooth 2x60 amp controlers, would they do? And do you think they could take the two motors? Any help would be appreciated, and this is basically our last day building the thing so speed is of the essence! Thanks

sounds like your gear ratio is set too low. I would assume that the motor is drawing too much current because the motors have low torque and can't turn to get the bot going. Put in an extra stage of gearing and you should be ok

We dont really have the time or space to do that, so we are trying something else first, according to the instructions for the syrens, if the Nimh or nicd battery's are depleted or can't supply the current the controller would blink like it is doing, so we are going to try it with the lead acid out bruiser and see if that is the problem (I wouldn't be surprised as there cheap eBay ones with insurfisient wiring, and one cell on the spare battery was already broken, so we gonna tey the lead acid.

wire it up to a 12v power supply and you should find out if it's the batteries or not

Don't have one, it drove on the lead acid at first, but then slowly died after a while, so I think the battery ran out, will try to sort it out.

Alex, you can come and it test it at my place any time.

Even the replica Speed 900's have enough torque to get a feather going at a fair clip.

But 25A is low.
We simular problems with Kashei, and that started with a Scorpion XXL Ilyama version.
But 6S A123, 100mm wheels and a 4.5-1 gearratio is too much for those. The current limiting acted up from the start.
We solved that with a Sidewinder.

In Hannibalito III we still drive with the same drive, Speed 900, Scorpion XXL Ilyama version, 4.5-1 gearratio, 100mm wheels , but 4S A123. After all the years we use H III, no problems on the drive tough.

Satanix 1.666 flies around with Speed 900 6-1 gearratio to 130mm wheels, 5S LiPo and a set of Victors. No failures like you describe.


Fastest solution, try on a lower voltage.

Yeh, we have found it works better on 12 volts, so we'll probably try to change it.