Txmustangflyer

Its a street cruiser rtr thing, although it loves yo hang its tail out in a power drift as much as you want it to..it doesn't seem like the 4tec 3.0 gears are designed to hold up. I was not doing full throttle truns, or full throttle drifts..I did do some full throttle donuts, but that was before switching to the hotter pinion gear.
As this is my first full blown (as in more than a 150 bucks) Rc 4 wheeled (I fly rc usually) I'm not sure what I did to cause the spur to have stripped on its 2nd pack ever. Did I overheat to motor and pinion and basically melt it? Second pack the motor was hot enough to burn flesh. That was right after the spur stripped.
I am assuming, at this point, thats probably the cause.
So..
A. How do I keep it from happening again?
B. Should I consider a metal spur gear? If so, Who makes them?

RustyUs

It sure looks melted to me. Maybe it was a combo of spur/pinion gear mesh being too tight, and over heating the motor. My best guess would be the mesh of the gears was too tight that helped cause to over work the motor, and thus creating even more heat. I'm not gonna be much help telling you there should be a "tic" of play (ever so slight bit of movement) when you rock the spur gear back, and forth when checking the spur/pinion gear mesh as I so believe the stock mount has fixed mounting positions depending on pinion tooth count you are using. I'm not sure if there is an upgrade for the motor mount to be able to set the mesh yourself. Check Hot Racing out. That would be the first thing I'd replace.

I've used 48 pitch gears on some very high traction surfaces with some 5.5T/5700kv motors and composite spur gears can handle a pretty good amount of power... if things are properly aligned. You would think Traxxas spur gears would be able to handle lots of power since there is a VXL version of the 4TEC that is 3S LiPo "capable".

Also, if you have the RC apart, I'd recommend checking the bearings to rule out any additional binding that may be in there.

RustyUs

There was one other RC lineup that I did follow, and that used motor mounts with fixed motor positioning. I'm not saying that is where your problem lies, but it was a big stink on costumer satisfaction, and was quickly recommended to be one of the first things to upgrade.

Txmustangflyer

The bearings check..not rachety, but smooth.

I think I goofed when I went from the 19t to the 22t. I didn't realize I needed to change the mounting position. Like I said, I'm an rc 4wheeler newbie..
My grandaddy always said, if it ain't broke, don't fix it..lol.
Guess I should have taken a closer look at the mount.

RustyUs

Oh, and that is a great looking body wheel combo by the way.

Since they are cheap, I would buy a handful of spurs and revert back to stock gearing. Keep an eye on motor temps every couple of minutes to find the sweet spot pinion gear needed to keep temps from getting outta control.

Txmustangflyer

I ordered 2 72t spurs, also the adjustable aluminum uppers for front and rear suspension..what the heck, right?

Txmustangflyer

And now I've been pointed to Hot Racing..oh the credit card is gonna scream..

Aluminum motor mount on the way..its the same between v2.0 and v 3.0.
Also found a 70t spur (Steel) and a selection of pinions.
I'll run the traxxas plastic ones till I make sure I'm setting the mesh right then start playing with the ratios.
Aluminum adjustable upper control arms front and rear. Keeping the plastic lowers as a shear point Slowly working through, finding out what carried over from 2.0 to 3.0
Hoping the aluminum motor mout will also act as a bit of a heat sink for the motor.

Txmustangflyer

Uppn further exploration I'm an rc car newb. Was supposed to move the motor to the corresponding holes for the pinion. I'm an idiot lol.

I'm slowly finding aftermarket parts for this chassis but its slow going. What wotks for the normal v 3.0 may not work for the factory five bodied cars. The wheelbase is slightly stretched (via the lower control arms and bulkheads) so those definitely have to stay stock.

Front brase is the same, the battery hold down is not, motor mount is, gear cover is (but nobody has any in stock that I've found)

I'm sure I'll, eventually, go brushless but I want the chassis prepped before then. Doing the "easy" upgrades until I learn more about how things come apart and go back together.

Txmustangflyer

So, in talking with some local guys around San Antonio, I can a. Turn the Traxxas into a speed runner, or B, an awd drifter, ir c. Leave it be.

Where's the fun in leavin it be? (Damn..soundin like the rest of you...whats happenin to me? )

So, knowing from online soyrces, vids, etc, that without upgrades I'd probably be doing a weekly parts order anyway I flipped a coin, ignored that, and looked at where this rc will typically "hang out."

The answer became kinda obvious, fast. Awd drift. It kinda likes to do it anyway when it corners, why not encourage it.

So..heres the parts list coming.
Traxxas: 72T spur gears (2) Aluminum lower control arm mounts, adjustable upper links, rear diff locker (back ordered)
Hot Racing: Motor mount (aluminum) Gear cover (Aluminum) it also looks to act as the rear bulkhead brace. 70T Steel Spur, pinions from 24 to 29t package. These won't be used for speed but to broaden the throttle...I'm old, I need more room :-) A locker from them, as well, since traxxas is back ordered.

GPM: Front brace, front and rear steering knuckles, front castor blocks, aluminum servo daver with aluminum servo horn, aluminum steering assembly.

beyond that is a holding pattern, the rear bulkheads, diff covers, and liwer control arms are factory five specific and no one that I've found, makes aftermarket upgraded pieces, as yet. The 4tech sway bar kit, as a resutlt, also won't fit. I'm hoping that I can compensate using shock oil viscosities instead. It may mean buying a second set of shocks, etc so I can set up and try different viscosities on the fly vs tearing them down all the time. Dunno on that yet. Another tweak may happen in the springs, but with how it ran, stock, before I fubarred the gear mesh, leads me to think I shouldn't have to mess with them too much. Even in a drift it was smooth. Not any chassis roll that I noticed, and any bumps didn't cause anything adverse to what I wanted it to do. But, with all the new parts, its bound to behave different.
I've also decided to chronicle, as much as I can, on video, my first real forray into rc cars. What fits, what works, what don't etc. I'll post links when I can

Txmustangflyer

Being an OTR truck driver, The repair has not yet happened but getting notifications of deliveries...a lot of parts are arriving (yay!)

So the repair/upgrade should happen first week of June.

TheRailroadBull

I 100% believe this was a gear mesh issue. I would also recommend to NOT use metal spur gears. Pinions and internal transmission gears are more expensive than a spur gear, especially a Traxxas one, so it's best to leave the spur plastic so that if there is a failure in the gearing, then the load falls on the cheapest gear possible. Just my $0.2.