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Hey gang,
I just rebuilt my stealth on my RC10T. I built it to spec etc. transmission is moving very smooth and quiet now.
As I was doing a final check to set my slipper clutch I noticed while holding both tires from spinning and giving short bursts of throttle my truck's front end won't lift up. The pinion gear isn't even spinning. The motor just rattles like its locking up. It seems like my battery might be on the low side. I don't think that's the issue though.

I'm all ears for any advice.

What motor and gearing etc.? Some motors struggle with either a tight slipper or big gearing.. Charge your battery first,always best for setting things up after a rebuild.. For stock motors I find the best way is to just accelerate hard and let it slip for couple of feet on the surface you usually run on..

can be motor (brushes, comm), batts...

It's a castle 5700kv using sidewinder 3 esc powered by 8.4v nimh

18p 87s

Ha. My bet's on a dead battery... 7cell nimh is usually a red signal in my "troubleshooting" book

Try another battery to start with... and let us know.

I wouldn't even use the lift front tire method. I like the hold one tire (right side) with your arm against it holding it against the tabe, hold the spur gear with your fingers, and with your free hand try to turn the other tire (left side).

Top shaft turns your slipper is slipping first.
Top shaft doesn’t turn your diff is slipping first.

Always make sure the slipper slips before the diff.

On another note while driving a barking sound is the diff slipping while a smooth high pitch sound is the slipper.

Fresh battery.....same results. I've used your method in the past rc10th. Guess I'll just resort to my past methods.

Did it work for you or not really?

Charlesmtb wrote: The motor just rattles like its locking up.

A 5700kv BL is a rather decently torquey motor. it SHOULD lift the wheels, esp with a locked slipper (and a non slipping diff...). Especially with a rear-motor'ed car like a rc10. But it does eat up a significant amount a current to spin, esp. under heavy load. I still say dead batteries (or at least only partly functional) as the likeliest culprit . Both batteries. The car will "drive" when less load, but the batts can't provide enough to feed it well when wheels are stuck.

Other things to investigate: other than motor disfunction (blown rotor, bearing, whatever), solder joints and connections.

I'm still betting on the batteries

the other possibility, is the motor sensorless? in a locked rotor state, like trying to keep it from turning, it might get into a cogging issue where it essentially just kinda buzzes in one position.

No the front end did not pop up with the fully charged battery. I don't think there is any connection problems with the soddering unless it's an internal issue with the motor. Listen the truck moves gets up to 40mph and is super quick. But I was a little disappointed she never popped Wheelies.

Getting back to my diff. I built it under the guild lines from racer53's utube video. Did the whole "break the diff in" process. The tranny sounds and moves smooth but I have to say I think I may have my diff tightened down so much it's to tight.
Still with my slipper tightened down to full compression of the spring the truck WON'T pop up when I punch the throttle holding both rear wheels. The motor just sounds stressed and slowly turns the pinion like an compressed air ratchet struggling on a seized nut.

And I have no idea if my motor is sensor less. All I know that the esc is programmed to give 100% power when I depress the throttle.

JWSCAB.....that's how I would describe it.

jwscab wrote:the other possibility, is the motor sensorless? in a locked rotor state, like trying to keep it from turning, it might get into a cogging issue where it essentially just kinda buzzes in one position.

I have had this exact issue with a sensorless motor.

What slipper are you using? I have the same Castle SW3/5700 combo in my 10T and it will flip over backwards, but I had to upgrade the slipper to the new T4/B4. The original slipper is just too small to handle all the power the brushless has, she would slip forever if I punched it. Had to ease into the throttle if I ever wanted to get to top speed. Do you have the Castle Link software? There are a ton of options to adjust, way more than what you can do with the remote. If you bought it second hand, they may have it programmed to limit torque or changed the throttle curve (thats how I have my set up so I can drive the truck without popping wheelies).

I got the combo brand new out of the box. The only thing the LHS did was turn off the low volt cutoff for lipo and increase motor break to 20%. No other changes were made to throttle curve etc. I currently have the original slipper and was interested in upgrading to a lightweight top gear and v2 slipper. I just have already put close to $450 (including battery and charger) into the truck and wasn't crazy about spending anothe $40 just yet. But if that's what it takes to up the performance then so be it.