operative

Ijust bought a Hobbywing Brushless kit for my Exceed Sunfire.

I got the B4 Kit: http://www.nitrorcx.com/ezrun-brushl...-combo-b4.html

In the instructions, it says to use: With 4-6 cells NiMH/NiCd or 2 cells Lipo: On-Road≥5.5T, Off-Road≥8.5T;

Well, I put the motor in, and tested it with a 7.2 V NIMH battery and the car was very jittery if you went straight to full throttle. It would never get up to speed as it would jerk forward and then brake... then jerk forward again continuously until i let of the throttle.

If instead Islowly pulled the throttle back, the car would start to accelerate smoothly and then once Ihit a medium speed, Icould launch into full throttle.

Itried a few different configuration settings of the ESC, but nothing changed the behavior really.

Ifigured Iwould try a 3s lipo battery for kicks. There was no jitter in the throttle. It worked perfectly.

The only thing Ididn't try to adjust was the timing, could this be my problem?I'd rather be able to use my 7.2V NIMH batteries since Ihave a bunch of them.

Thanks!

nitrosportsandrunner

what you are describing is often called cogging.
its happening most likely because you have a hi KV motor(most off-road rc's, especially 4wd, work better with motors in the 3000kv range)
and you may have it geared too high. try a smaller pinion gear.
also, the timing will have some effect. advancing the timing is kinda like gearing up. so, set the timing to "0".
also, if the instruction say use 2s, not 3s....then dont use 3s! the 3s with the higher kv motor could damage the motor!
hope that helps.
i have the same buggy, only with a novatech 75amp ESC and 3300kv motor. no cogging here, this thing shots off the line!

XTEAMRC

We are X-TEAM and we come from CHINA,we profession to produce some kinds of brushless motor ,we hope can help you a lot,and give you a choose ,we can take OEM ever you want,