FD 1/8 Buggy Stutters - RC-Monster Forums

**FD 1/8 Buggy Stutters -** 12.30.2006, 08:00 PM

Hey guys. I picked up a used FD 1/8 Scale buggy. Torn it down and rebuilt it so I know all inerts of the buggy are ok.
Got it all hooked up programmed the 9920 and disabled the BEC, Running a 5 hump 1400mah and a JR AM radio.
Here is the issue: I can ease into the throttle and it goes ok - sometimes even at 1/8th throttle it will stutter (like the motor turns off and then back on). When I attempt full throttle it hesitates like crazy trying to find its self then it will grab but will soon release (stutter or shut off/on the motor) I almost makes a barking sound.
Any ideas?

Thanks

Sylvester · 12.30.2006, 08:04 PM

What motor? Maybe try a UBEC .

12.30.2006, 08:06 PM

The motor is the Nemesis XL. I tried the UBEC on the 9920 but same problem

Sylvester · 12.30.2006, 08:08 PM

Hmm, i am not positive but it can either be a problem with the motor or esc. Would you possibly have another esc or motor to try out ?

12.30.2006, 08:10 PM

Can I take my MM ESC off my ZX-5 and use that one? If not a wise decision, then no I dont

Sylvester · 12.30.2006, 08:12 PM

Yes you can, that should be able to tell you and us what the culprit is..

12.30.2006, 08:35 PM

Thanks - but can the MM ESC handle 14.8 Lipo battery ok?

BrianG · 12.30.2006, 09:10 PM

Quote:

Originally Posted by BigSushi

Thanks - but can the MM ESC handle 14.8 Lipo battery ok?

Yes. It handles 12 cells, which is 14.4v nominal, so there is no reason why it won't handle 0.4v more of a 14.8v 4s lipo pack. Even right off the charger, 12 NiMH cells is 16.8v (~1.4v each), which is exactly what 4s lipo is. And then, the ESC has a built-in LVC setting for 4s too.

Sylvester · 12.30.2006, 09:19 PM

Yea, just dont forget 4s lipo fresh off the charger are (~4.2v each) which is 16.8 so it is equal to 12 cells. Some people have even tried 5S with sucess.

12.30.2006, 09:22 PM

Cool - thanks for the help!!

Sylvester · 12.30.2006, 09:30 PM

Anytime! - report back when and if you find out what is causing the problem.

coolhandcountry · 12.30.2006, 09:55 PM

Make sure to pull the red wire out of the rx plug.

12.30.2006, 10:45 PM

Ok, got it all hooked and all out of the buggy. All seems to be ok at the moment. I tested forward reverse. Motor gets warm but everything else is cool. It only studdered twice but it is nothing like it was b4. Gotta love the MM esc! Only bad thing I can say about them is - what the hell kind of solder do they use to solder the wires to the board? It took forever to get it to melt!

Sylvester · 12.30.2006, 10:52 PM

Ok, so the esc was bad... Its not the solder they used, is the way they soldered it, i bet they must use a VERY hot machine or gun to sauter them!

12.30.2006, 11:18 PM

Quote:

Originally Posted by BigSushi

Only bad thing I can say about them is - what the hell kind of solder do they use to solder the wires to the board? It took forever to get it to melt!

Sounds like you need a larger tip for your iron. Big gauge wiring requires a lot of energy to get it heated up quickly. The only way this happens is by having a large enough tip that can sink its stored energy to what it touches. Bigger (thicker) tip, more stored energy.