Yea. I was thinking the same concerning the Mamba Max. Maybe somebody would be brave enough to replace the caps on there 125B with 50V ones to see if thats the problem...

I would do it, but I dont have a Quark. Maybe if you give me yours....

Haha...I WISH I had a Quark...

Shawn at CC once said that the caps should be rated 20% higher than the voltage going into the esc. This statement was in response to my question about whether or not the MM could handle more voltage than 4s lipo.

I've heard most manufacturers of caps underrate their working voltages somewhat as a safety margin. So I wonder if higher voltage caps would do anything at all??

Most circuit designers tend to use caps up to 50% higher that the working voltage. However, higher voltage and/or higher capacitance caps are physically bigger and may not fit in the small spaces found in an ESC. You could add caps outside the ESC, but at high switching frequencies, you want the caps as close to the circuit as possible so that's a limiting factor as well.

The next time someone has their Quark apart to repair the thermal material, they should try installing some higher voltage and higher capacity low ESR caps as a test. IIRC, smhertzog has his 125B circuits exposed so he could install gargantuan heatsinks. Maybe he'll be the guinea pig? :)

hello,
first , sorry my english..

i think i find my problem , i have two new quark125(just difference wire color).
i open one esc to remove alum and soft pad, top and bottom.
so i am try use Thermal adhesive the FET with alum panel, and adhesive to case.(just very very tight)
i am use 18cell Ni-Hm GP4300 battery and Feigao 7XL for testing,
i find FET heat very quickly transmission to case. and just great.
i comparison other esc heat not quick., and heat down as soon.

maybe soft pad not sticky all FET(i open found some).

i don't know i do this is right or wrong, hope this help.

Thank you.

just bought a Quark 125B
 

Hey, i just placed an order with RC-Monster for a Quark 125B last week (i love the name! ;))

My first BL setup going into a 1/8 BL emaxx truggy conversion:

-Quark 125B
-Feigao 540C 7XL
-5 cell, 2P A123 custom made pack :)
-UBEC

As soon as i get the rig up and running i will let you know how it runs!

Welcome aboard Zeropointbug!

I have a question about new quark 125 (color wire ver).
something set can't be save it like Drag Brake , power off then on seting will goto factory default.
but old(white wire ver) is fine.

i think program is differ.

I've had this happen to my "old" white wire version. You program it to a certain drag brake level, then exit. Then if you go back in, it is still at the default setting. Is that right?

Well, actually try it once you exit. I've found that even though the programming seems to revert, it actually doesn't. I programmed the DB to, say, 50%, then exited. I then ran it and it was definitely set to 50%. When I got back in the programming, it seemed to be set to the default value (3%?).

So, to make sure everything is where I want it, I go through all the options and set each one to what I want just to be sure the settings are holding.

At least that's how it seems to work on mine...

neon wires?!
 

Well, one of the reasons i bought the Quark was its kick-ass looks, one being the white wires. Now i hear that they've put neon colored wire on it?

If anyone has white wires that are willing to part with them?

Zeropointbug

Thank Brian,

not, i am set all setup complete than try run that function drag brake ON.
but switch off power or left battery then put back battery or switch on,
that drag brake just go back OFF.

used same setup for old ver it's normal.

i don't know why..

guess program is differ.

the wires are just soldered on so you can change them to whatever color you want...

If I'm understanding you correctly, it seems like it's not holding its memory. That is weird. I'd give Quark a call and see what they say...

How do you tell if it is on default or not?