rotarypower101

I have gone through 2 Novak Super Duty XRs, over time they seem to just drop fets and loose power.

Admittedly I am pushing them fairly hard, but I keep a fan on the heat sink.
It is running a set of 550s geared way down and pushing fairly hard on a very large heavy vehicle.

But my friends old G12 Tekin forward only seems to be holding up better and he doesnt even run a fan.

Is there a stronger more reliable ESC substitute I could get that has both forward and reverse?


Any ideas or suggestions?


There is no issues with binding drivetrain, everything seems OK, just after enough time the ESC seems to give up.

Is there a tutorial on replacing the fets of a SDXR with appropriate part numbers ?

http://www.youtube.com/watch?v=IxNDwTfxL5k

dethklok151

iTrader: (65)

I ran my kids 6volt chinese power wheels with two traxxas xl5 brushed esc's . i think they were just "wyed" together on one 2s lipo. did just fine running him around. I even thought that just one would have worked. That one was stock though and just cruising a 2 year old. We moved on to a modded 4wd power wheels and then on to the razor 24volt quad. chain drive and airfilled tires. Those razors or knockoffs are the best platform to vet crazy. They will even haul my 225 pounds around our rc track.
Tell us a little more about your application, it doesnt sound like there is kid in there...

WindDrake

iTrader: (13)

Check out the Traxxas EVX-2. Comes stock in the Summit (single motor config) and brushed E-Maxx/E-Revo (Dual 550's). Huge amp carrying capabilities and the new versions have LiPo LVD.

dethklok151

iTrader: (65)

It could be your motor choice. I tried to run a pair of 27 turn stock motors in an emaxx one time. I do t remember what I geared them but they were really fast and burnt out just as fast. Maybe 550 sized motors would help.
I beleive the traxxas evx esc is gonna be similar in spec to the super duty novak.Hpi makes a dual motor esc, I have also seen a chinese dual motor esc in my searches on ebay. I cant say which one is best. Kershaw designs carries a pretty cheap 550 motor.

Dave H

Perhaps robotics motor controllers? Here is one source with a variety of models, sure there are others if you search some. Granted the ratings don't appear immediately impressive, but the bigger ones are fairly large with significant heatsinks, and mention ride on toys as well as substantial weight robots. And if I'm not mistaken there is some reason to suspect that not all RC ESC amp ratings are exactly what they might appear to be.

Sabertooth dual 60A motor driver

rotarypower101

Its a Jeep Hurricane running a blue top optima, full RC steering and drive, with a switch on 3rd channel that flips it over to manual drive by wire.

Thats one of the other important factors, the ESC will need to comfortably take 14+ Vdc

It runs kids all over the place, and quite often, many many miles.


I popped in a matching rotation and counter rotation set of these I got off of ebay super cheap to replace the motors, one of them was feeling kinda low on power and was squealing a bit.

Are these motors very different from the most basic stock form of this motor?
Do they change the timing at all / significantly?

rotarypower101

This thing looks really good, Thanks!

How reliable is the traxxas stuff?
I have read they have made a very large leap from the days when I knew them, but its hard to change my preconception of who they were, with what the consensus of who they are now.

What should one expect to pay for a good used unit?
And where should I be looking for a good deal?

Thanks

meno1103

iTrader: (6)

+1 on the EVX2
:sigh: I sold an almost new one with two 550 titans and threw in a used 775 as well all for around $60 a while back, and I keep running into threads like this and actually now have a project where I could use one
I see them pop up for around $60, some with a motor or two.
I think the reverse rotation motors have some advanced timing, as it makes sense to label them as such only if they have it, otherwise simply switching the motor leads will effectively reverse it. If you need to use counter rotating motors for your project, you could check to see if it has timing by powering it in one direction then the other, listening for changes in the pitch. Obviously, higher pitch noise from the motor means higher rpms.

WindDrake

iTrader: (13)

^ What meno1103 said above Re: Rotation.

The EVX2 in my Summit (powering a DeWalt 14.4v 840 Motor) has been fantastic, and held up to all sorts of abuse including submersion, snow, and long trail runs with multiple packs back-to-back for well over a year and a half. While I may not like TRX's brushless ESC's (WP is nice, but they don't contend with Hobbywing now) - the Brushed ESC's are rock-solid. When I build a Trail Rig later this year, I'll likely be using the new EVX2 for the LiPo LVD and Waterproof capabilities.

rotarypower101

Thanks.

Just wondering as they do not look any different between the CW CCW motors, as in where they are keyed in and any physical differences I could discern.
[if I were to guess they are very close to 0* timing and internally opposingly wired]

I think most of these closed endbell motors are a ~0* timing, but I have mot researched anything about these, as it was not important, just figured as long as they are matched and opposing rotation I would be A OK!

The Novak ESC seemed to very shortly after installing these motors, go out (within 3-4 runs), which could be due to the motors....
But most likely was just a coincidence. (crosses fingers)
The Titan motors were very very new and ran just as I would have expected, and RPM VS amp draw was very similar.

Just sucks when you have two variables to contend with, causing a bit of uncertainty.

Here is a big question, which I am sure is a non issue...
Cheap ESCs used to not have very many steps in their throttle curves, I assume that this is no longer a issue at all, specifically with this Traxxas EVX-2?

rotarypower101

Yes from memory it did have a pronounced change in RPM from reversing the leads IIRC.

It was my only test that they were legitimately a matched counter rotating set.

WindDrake

iTrader: (13)

I don't think you're going to run into that issue. The stepping in my older EVX-2 is great, you can launch the truck very slowly even in 2nd (High) gear.