I've always had good response with Tekin, be it a warranty issue or just a general question.

Hey folks. I bought a 1 race old RC8B4 with the Tekin RX8 G3 1900kv setup installed. I'm positive that its all one race old. My problem is, I lose motor power sometimes, steering is fine. It happens all the time when I snap throttle WOT from a stop. Like at a race start. It will move a couple feet & shut motor power off. Sucks in the main when you TQ lol. I can make it do it 100% of the time. I've replace sensor wires etc. Not a noob. Rewired everything. It will work fine if I ease into the throttle. On the bench when I make it happen by snapping WOT, it sound like the RPM are higher than if I ease into it. I've reset the ESC to factory spec. I've gone thru all the settings. I'm not a Tekin expert. I've mostly used HW. That being said. I don't have the current hotwire. Also it seems down on peak power. I've done throttle learning multiple times. Any ideas?

A data log might show us something to get an idea what is happening to voltage. A bad battery or a bad connection can cause a lot of voltage drop under load. If it starts a new data log when it happens then it is resetting completely. If it is resetting it is looking for neutral signal so if you keep pulling trigger it will not go, until you let it sit in neutral for a few seconds so it can reboot.

Are you setting Low voltage cutoff to 4s? If not as a test you can set it to 3s or 2s just to see if it is hitting LVC.

Thanks for the reply. I've checked battery connections every time it happens. I can make it do it on the bench every time. The ESC is not resetting. If I keep my radio trigger @ 100 throttle, the ESC will beep and flash 3 lights @ the end of the line of leds. I've also messed with the VC setting and it doesn't seem to change any. Thanks for the help. Everyone keeps telling me how this is the best ESC on the market & once I sort this out, I'll love it.

Sounds like it is resetting if it flashing the right 3 leds when holding throttle on. When it turns on or resets it is looking for neutral radio signal and since it is getting a full throttle signal it is showing the radio signal too high code. Exactly what the leds are doing help us diagnose issues. When you release throttle I am assuming it chimes again and then is ready to drive again. I also assume if you cleared the data logs and then caused this issue you would see 2 runs or more in data log. Be helpful to see those data logs if you want to send it to me.

Could be an issue inside the esc, but need to eliminate all the other possibilities. Try different battery. Even though connections look good there could be a cold solder joint with a lot of resistance and under heavy load the voltage is dropping very low. If it drives good other than when you quickly pull full throttle it is likely a voltage issue and need to figure out why.

Just curious, does a G3 Rx8 have anything like boost or turbo timing?

Building a new Ebuggy and Im not sure if a 1900 is the best choice. Usually an extra tooth on the pinion helps keep the nose up on our intensly hard to hit jumps. But costs some braking, and heat. A 2050 seems like a better choice outdoors.

My refurbished G1 has been the toughest esc Ive ever had. (Xray battery tray mounted so, some give underneath, like a diving board).

It was stalling for a second on long runs, must have overheated. Like a throttle only glitch. Or cogging. Opening up the buggies body at the rear and front cured that. I didnt even know I had the overtemp shutdown enabled.

Rx8 uses dual mode so starts sensored and switches very quickly to sensorless. It has boost, but it is called timing advance in the sensorless mode since it is not 'boosting' on top of the physical sensor timing. It also has Turbo. Both timing features are limited to 30deg due to being sensorless. Honestly not many use extra timing in a 1/8 setup and most are trying to tone down the power. Timing may have some use on really straights for extra top speed, but on the rest of the track consistency and smooth power is really the key to fast laps.

Thanks.

Just need a hair more wheelspeed sometimes to get the cars nose up on fast jumps. Speed is fine on the ground. Timing sounds like a better idea than a gear change.

Are you using any current limiter to tone back the power on the ground? The newer version of the Rx8 has a Torque setting that allows you to dial back the power on the ground but still gives you that instant snap in the air to bring nose up when needed.

Yeah, current limiter at 75%. Epa on the radio is 100%. 20%+ expo on throttle, -20% on brake.

This is a rare jump where I'm already ripping, so not as much wheel speed left, like a normal jump. Grab the lip wrong, and up comes the rear of the car. Going up one tooth on the pinion, more than solved it.

Just wanted to make sure my next build has some timing adjustment for such oddities. Thanks.

Both.

Hi Guys,
I'm new here and I come from Germany.
I will use the RX8 Gen3 in my MT410 2.0 with a TPpower Motor (3640 with 3650KV on 3S)
This rig fits perfect and should be run amazing, but:

I can't start up slowly.
The car begins to roll and after a second, it accelerates without pushing the trigger.
It's hard to explain, so I 'll show You:

Edit: I cant't add a YT link, because I'm new here. But I will post it later, when it's allowed to me.


Do You have any ideas, how to fix this?
Its not a problem with the radio, I tried different...

Thanks a lot for any helping idea!

Rx8 Firmware: 291
Motor: tppowe 3640 (3650KV)

forums rules says, after two postings, I can add links and photos...

Look at how you have the throttle curve programmed on the ESC and potentially on your radio as well. Ensure your calibration on the ESC for full throttle/reverse/neutral is set as well. Resetting everything to a linear curve will make troubleshooting a bit easier. Having negative expo (twitchy throttle) could create the behavior you described, but it could be set in either the ESC or the radio (or both).

The leds on the unit are the key and tell us what the radio signal is doing. Look closely at them and when in neutral it should be flashing the center led, and then led 1 every 2 seconds for the temp reading. If the unit is hot it may flash 3 or 4 leds every 3 seconds. When you pull small amount of throttle it should be showing led 1 and then climb as you increase throttle. Same with brake starting on right side and increasing to the left as you increase brake.

It could also have a bad throttle curve in it. If so you need to change the throttle curve using the Hotwire to any other curve and save, and then change it back to #3 for linear and hit save again.