Troubleshooting a Fusion Pro 2300KV

[xagoras]

I went ahead and installed the Fusion Pro on my TRX. Did all the pre-run procedures, went through the setup etc.



I thought it was going to be a plug 'n play installation like my Axe, but no.


It behaves very strange. Firstly, it seems to limit power once the throttle is fully pressed. Acceleration is normal up to a certain point, and then it just drops the wheelspeed. It even seems to stop and start again on straight lines. Kind like losing signal or power momentarily, but not exactly.


While climbing, there have been situations that I could hear mechanical movement, but there was no wheelspin at all.


So, I'm trying to understand what the issue is here, before I start tearing apart the rig. Is it a loose slipper clutch that causes this? Could it be overheating of the motor?


If I keep a slow steady pace, everything work smooth as butter.

[DrIsotope]

Sounds like something is slipping somewhere. I have three Fusion Pros now (and 4 non-pro Fusions) and never have any weird behavior from any of them.

[Fallen]

Hmm... I don't have a TRX-4, but I have owned Traxxas models before and had similar issues.

It turned out to be a sheared drive pin on one of the shafts that a transmission gear was mounted on. That drive pin transmitted the rotational force into that gear, but the pin had sheared.

The gear was a tight enough fit on the shaft that in low power applications, the shaft itself would transmit rotational force into the gear.

But once you asked for some power from the transmission, the sheared pin would show itself. The transmission was spinning, but the driveshafts weren't.

Sound similar?

[HumboldtEF]

Yeah I agree it sounds like a mechanical issue. Maybe that HH motor you just had issues with wasn't to blame either?

[xagoras]

It's the same rig. Drag brake is rock solid with the Fusion however, no matter how steep. It was the first thing I tested

Fallen's description pretty much covers what Im trying to say, during climbing. Could this be related to the drag brake issue too?

[Fallen]

Well, when the problem occurs, does your:

1. Transmission spin?
2. Driveshafts don't spin?

If both, it's not likely a drag brake problem and is likely a mechanical failure inside of the transmission.

If your:

1. Transmission does not spin

Then it very well could be an electronic issue, and possibly drag brake related.

[xagoras]

OK, reviving this since I haven't really solved it although I've literally tried everything. I went ahead and stripped the whole truck down, cleaned the transmission and axle gears from the grease and put everything back together. All seemed pretty good.

Changed the pinion gear to a 9T and even replaced the TQi with a Flysky FS-GT5 because I thought it could be a bad trigger causing the issue. Calibrated everything and hoped the issue would go away. NOPE!

Still doing the same thing. If I go full throttle, it will put itself in a slow-speed state. If I let go the trigger slightly, but not completely, it will pick up speed. However if I accelerate very-very slowly it will be linear. No throttle cutoffs. WTH?

I'm one step away from contacting my LHS about this. Any ideas?

[Valor]

do you access to a known good motor that you can install and confirm or eliminate drivetrain issue?

[xagoras]

Originally Posted by Valor

do you access to a known good motor that you can install and confirm or eliminate drivetrain issue?

I had a 1080 HH Crawlmaster Sport combo in that rig prior to installing the Fusion. With the exception of the worn drag brake, it worked perfectly well.

[xagoras]

Today I tried recalibrating everything again and had another go, but still the same. So went ahead and installed back the 1080 and HH Crawlmaster Sport. Guess what? It worked flawlessly. So I guess, that leaves driveline issues out of the equation.