Worth upgrading from a 9920 to a Quark 125?
 

Hey guys, just hoping to get some opinions on the Quark 125, now its been out long enough for you guys to form some opinions :) I'm currently running a 9920 in my Savage, but I'm thinking of upgrading. Do you guys think it would be worthwhile to upgrade to the Quark? I'm hoping it would reduce the heat, have less cogging on pullaway and mount nicer because the solid case. The target vehicle is my Savage, which runs quite happily with my 9XL on 12-14 cells. I don't plan to bump the voltage higher than this, 16 cells or 5s possibly in the future.

Also, whats the support like with Quarks, if they break or become damaged? Anyone had any experience with returning damaged units to them? This is always a big factor I take into consideration when purchasing a new ESC.

Was also thinking of putting a Mamba in there..read of a couple of people putting them in 1/8 buggies okay, but I think a Savage will overstress it? CC gave me the unoffical go-ahead to run upto 16 cells on one, concerned it'd overheat too easily with a 9XL/14 cells though?

the quark is smoother in startup, it has a build in lipo cut off and it has got a solid housing instead of a bag...


the support on the quarks is flawless. Read Mikes topic about them.

the mamba is not good for 5S, 4S maximum. (or 12-14 cells)

At the min 14 cells is my max anyway, don't have enough spare cells to bump any pair of batts up to 16.

Smoother sounds good, will I still need to run a UBEC with it like I do with my 9920, or can I scrap that? Do you think it would run cooler than my 9920 under the same conditions? That doesn't get hot to the point of overheating, but after a hard run it does get a bit toasty.

So the support is quite good then is Mike is pleased with it. Will have a look for his topic regarding them.

here is the thread.

yes, it should run cooler than your 9920.

Thanks for the link mate.

Does the Quark have brake/reverse disable?

yes:018:

It hasn't got a reverse brake though. That's the only catch.

Actually, it is there, but it's all but useless. If you gently squeeze the throttle VERY VERY little while its still rolling in reverse, it will brake nicely without that abrupt stop. Not good for panic stops unless you have very good control. However, the throttle range for this is about 2mm. Activating drag brake seems to help, but I don't know if that is just my perception.

Arh well.. WHo needs reverse anyway.. you can set the reverse epa to 30 percent or something, so you don't go too fast without a brake (or allmost no brake)

Thats what I do. EPA on reverseis set to 25%. Just for backing out of trouble spots.

As far as upgrading to a quark..... I had a 9920, Its gone now and i am running 2 quarks now and working on the 3rd. Trust me, you won't look back.

What did you observe in heat difference hautz?

In all honesty right out of the box, I think the 9920 might have been a little cooler. But... by adding heat sinking to the back of the quark I can hardly even believe how cool it runs. The diference for me is the quark is easy to add a heat sink to if you need it. The 9920, you pretty much have what you have. Its not so easy.

No reverse brake = no big deal for me, Savage only goes one way and thats forwards. I don't have any other cars I plan to use the ESC in at the moment.

Curious to hear what sort of heat difference you noticed as well Hautz.

Edit: Thanks for your reply Hautz, didn't see it while I was typing this one :)

I am surprised it doesn't stay cooler. it should run cooler. Anyway, its nice that it's decent packed, instead of a simple plastic bag..

Indeed, this is my main motivation for upgrading, along with the hope its smoother at low speeds than the warrior. I'm actually happy with the 9920 other than its very exposed design, but a friend has offered me $180 for it, so i figure why not upgrade..

Also..my warrior stutters for a sec or two when I'm going say 5mph, and hit full throttle. I'm guessing because the amount of power the motors suddenly asking for. Does the Quark have any similar things like this I should be aware of?

The quark should be smooth, but your warrior shouldn't stutter when you go from 0 to WOT.

perhaps faulty cells?

Does it with all my packs, I don't think its the cells, they're matched 3700's, only had them since May, and have looked after them correctly with a balancing tray etc. Does it with my 3300's as well.

No leaking caps or a failing bec/receiver pack?

Using a 6v UBEC, which works fine - no stuttering on servo's. It only stutters going to WOT immediately, if I ease it in over the space of a second or so its fine. Its also fine pulling away to a medium speed, although it does cog for that split sec.

Caps aren't leaking, although there are only two on my model. 650uF 50v ones I think, not 100% though. One is easier to move around than the other, perhaps its become disconnected.

Btw do you know if the 9920 has thermal cut off? I've never encountered it so I presume it doesn't?

It still could be the ubec. did you tried reprogramming it, or do you have your epa set higher than it was with programming?

yes, it has got a thermal cut-off.

EPA's set to 100%, never saw the point in going over that with an electric. I tried reprogramming it a few days ago and haven't changed the EPA since then.

I don't have a reciever pack to hand to test with, nor any other ubec :( I'm going to order a new one with my Quark anyway so I'll swap them over and test then.

Suprised to hear it has a thermal cut-off, any idea what sorta temp it cuts off at? I've felt it get pretty hot before but its never cut-off. Mind you I'm not 100% sure what 180F feels like.

you need to realize that 50-53 degree C is too hot to hold. it feels like burning.

i would try a seperate receiverpack. or if you got the ability, hook up 2P of your 3700 cells.

True enough..think I'm going to go order a temp gun today. To my thumb theres 3 temps - cold, hot and burning.

What do you mean by 2P of the cells? You mean hook both up in parallel as a test?

Yeah, i doubt if they deliver the punch needed for the launch.

Running them in parallel makes them more than twice as powerfull.

I could run the car two batts in parallel with 5 mins of soldering.

To be honest its never been too big a problem so I've never given it much thought. But I'll run them in parallel this evening if the rain stops for 5 mins. Its probably just my batteries being a bit weak like you say.

That or another receiver pack. Please report back if you know more.

My girls truck stutter on 14 cells running the 9xl. but i think it too is trying to draw too much juice. i need like an 7 or 8 xl...it too runs on the 9920. Anywho, i think IMO, the quarks run way hotter than my 9920 with a fan. i have run the 9920 with 16cells and my 10xl geared 18/51 and no probs. But i can't run the same gearing with my Quark...i have to go down to 16/51...

my 7XL doesn't stutter at all, on 12, 14, 16 or 18 cells. it's just takes off without a fuzz.

you do use a fan on your 9920 but not on your quark?

I know Daniels quarks stays very, very cool on 5S lipo (set to 70 or 75 percent) it stays quite cold, even with his 'direct drive' centerdiff.

Hmm, if the Quarks going to run hotter, I may not bother. With the quark because it has a solid case, I could thermal epoxy it to the roll handle on my Savage to use that as a heatsink? I'm not running any fans in my truck at the mo, and would like to keep it that way if possible, so if I put a fan on and it fails, the system isn't going to thermal..

a heatsink needs to have a large surface, adding a flat piece of aluminum helps a bit, but it's not the purpose of a actual heatsink.

a fan helps removing the heat.. as long as the air is moving.

I run two 30mm 5v fans on the Quark. What do you mean set to 70-75 percent? What is it that is set to that?

Wow, two fans, proper heatsink case, and it still thermals. I'm suddenly gaining a new respect for the 9920's ability to move a 5.6kg truck without any fans etc. Espically with my "digital" driving at times.

epa on forward set to 70-75 percent. Not running it's full potential.

Ahhhh, don't get me wrong dude. I love my Quark, just takes a tad more to work with....Smooth as butter man.
Serum- hmmm, epa for throttle? or the program settign? meaning less.....what about my speeds??? I love my mach 2!!!!

Useless on some tracks. You can actually get better lap-times with the power tuned down.

right, but they are closing all the damn tracks here in MN!!!! So for now, i threw on my ti towers for a higher stance and ready for some bashing until i find a new track to go to. Then i can tune it down! I know it's useless for racing to have tooo much, but when i'm on the football field to tear it up....i want the top speeds and power...but as far as tuning down, you mean the epa on the radio right?

You got the DUH engineering Ti towers?!

got pics?

Yeah, have had them for about two months now, just never put them in. i'll get pics tonight, i tried last night, but they came out too dark. So i need to take them out in the sun or something.

How do you like them? i considered buying them in coorporation with the flexteks (which should be here now....waiting takes ages..) and GA skids.. (the thin ones)

I haven't tested them just yet. I just put them on last night. I like the fact that i can mount my wing right up. But, it makes my truck sit higher, which is not as good for me since i like the stability with the gorilla towers. Gets lower with those. Hoping my racer x and the ti towers will give me the proper stance i'm looking for. But for now, we will see tonight. i'll let you know how the work out and get pics to you soon ok?