Hey guys,
I have a problem with my Speed-T steering servo. I am using a MapAmps 8000hv 3s lipo. Under hard acceleration my steering servo stops working for a sec or two then kicks in. I since replaced the servo and receiver. Still same problem. I changed the cutoff voltage from 3s to 2s same problem. The steering is not binding at all. I really don't know what else to check. Could the speed control be causing the receiver to drop my steering? This is a very weird problem.

Any ideas would be greatly appreciated! Thank you.

It is possible that the motor pulls enough current to pull the BEC voltage down, I'd check that with a meter.

Sheograth,
Thanks for the quick reply. I am running the one of the highest mah batteries. Max Amps 8000hv 3s lipo. I only have about 4 runs on the battery. I also run this battery in my VXL Rustler and don't have a problem. Not sure how to check my amp reading when the car is running. Can the BEC settings be changed? The only thing that I have not changed was the speed control and motor. I also changed the battery. I have 2 of these monsters. I am at a lose. Any other ideas?
thanks!

See the battery doesnt matter. The BEC is the one thats modulating the current and voltage to the servo. You could have a battery capable of providing hundreds of amps at high voltage, but the BEC is the weakest link in the circuit. Heres what you want to do. Measure the voltage across the black and white wires going to the receiver, and then vary the throttle. The baseline voltage should be around 6 volts, see if it drops a bunch when you punch the throttle. If thats the case that means somethings wonky with the BEC or some other part of the ESC.

If that doesnt happen, then do the same thing on the wires powering the servo, that'll tell you if the receiver is somehow to blame.

Out of curiosity, what receiver and servo are you using?

I am using everything stock that came with the Speed-T. The gearing is also stock. The car came with a 2.4ghz radio. I changed it out with a Traxxas one that I had laying around and still had the same problem. I am pretty sure that the receiver is ok. Both show the same symptoms. The only thing left is the speed control. Going to cost me about $100 to troubleshoot. Hate to spend more money though.. I have a VXL that I use the stock Traxxas transmitter and receiver. No problem on the VXL. Seems to point at the ESC/motor.
By the way, the BEC is part of the receiver and not the ESC, right? I set the ESC cutoff from 3s to 2s, and just tried NIMH. Same symptom. hmmm....

Try what I said regarding the meter and voltage testing. The BEC is part of the ESC - it takes the voltage, this case 11.1, and regulates it down to 6 to power the receiver and consequently the servos.

Thanks Sheograth.
I'l give this a try tomorrow.

Sure, let us know what happens.

In any case, if it is malfunctioning get in touch with Losi - theres no reason it should be unless its defective, the speed-T is definitely designed to use 3s lipos and be able to regulate it down.