9920 usually jerky at low speed? - RC-Monster Forums

**9920 usually jerky at low speed? -** 06.30.2006, 05:49 PM

Just got my buggy running today. My initial reaction to the 9920 was extremely jerkey at low rpm, i gues it doesn't have many steps for lower speeds. The only other sensorless bl esc I've ever used was a schulze 18.97 which was alot smoother if my memory serves me correctly (over 3 years ago). Is this normal?

squeeforever · 06.30.2006, 07:36 PM

Its common to have cogging. Did it go away around 3 mph?

BrianG · 06.30.2006, 07:39 PM

Yah, there is cogging at really low speed on my 12020. I think that's why some people may prefer a sensored system for really slow speed.

Speaking of the 9920, does everybody's make "music" as you slowly increase/decrease the speed? My Quark doesn't do that. Just curious.

squeeforever · 06.30.2006, 08:16 PM

My 9920 does that. It gets higher pitched as the speed increases, right?

poconoblmaxx · 06.30.2006, 08:25 PM

I found that sound very usefull for freaking out the nitro guys. I usually creep around their trucks at low speed while they are trying to get them running.

06.30.2006, 08:36 PM

yeah the 9920 is loud. My schulze 18.97 did the same thing, but not as loud or noticable.

BrianG · 06.30.2006, 08:46 PM

Quote:

Originally Posted by squeeforever

My 9920 does that. It gets higher pitched as the speed increases, right?

Yeah. When I got it I thought it was kinda neat, but just thought it was a feature of brushless. If you do it right, you can play a tune. :) I am using it on an 8XL, but the quark is on a 10xl. I can't see this making a difference though. It's probably due to the switching speed of the pulses.

coolhandcountry · 06.30.2006, 09:12 PM

Are you having a cogging issue or is a real bad jerky type thing. I had this with one of mine and wasn't sure why. I sent it back to bk to get check out.

Sylvester · 06.30.2006, 09:24 PM

My 9920 sings to me! It really annoys my freinds when we are driving our trucks home, slow speed and some tunes are a good combo! ;)

Mike.L · 06.30.2006, 10:14 PM

Quote:

Originally Posted by Sylvester

My 9920 sings to me! It really annoys my freinds when we are driving our trucks home, slow speed and some tunes are a good combo! ;)

I hate it, but love it LOL:mad:1 :043:

Sylvester · 06.30.2006, 10:27 PM

Quote:

Originally Posted by Mike.L

I hate it, but love it LOL:mad:1 :043:

It gets quite annoying after a couple of minutes - agreed. But it sure does sound cool!

neweuser · 06.30.2006, 10:36 PM

mine don't sing, just chokes!

Sylvester · 06.30.2006, 10:41 PM

You must have a faulty system than! ;)

neweuser · 06.30.2006, 10:44 PM

LOL, that may be! Seriously, mine jerks a tad, but never very bad. It's like you can tell it's trying to find motor location, but like squee said, after 1-2mph or so, ZOOM ZOOM ZOOM! I took mine out with the 20T..and oh man...leaving dust clouds off the street! I can hear my crime fighters scratch before it rolls. not much for wheelie's anymore with the gorilla, it can still pull one, but it'll spin the tires a little first! fun fun!