17.5 2wd Buggy:

Can timing between 45-51
Stock Yellow Rotor
Gearing varies do to track size and layout. Take your current gearing, drop 3 teeth. This is with a motor fan setup.

4wd 13.5 Buggy:

Can Timing between 42-50
Stock Yellow Rotor
Gearing is around 8.5'ish FDR on most indoor tracks. IF you're smaller/shorter, gear down. Again cooling fan required.

FDR really depends on track size, but here's what I've found without using a cooling fan:

17.5 2WD Buggy
FDR: 7.0-8.0
Timing: 40-45*
Rotor: Stock Yellow
Fan: No

13.5 4WD Buggy
FDR: 8.0-9.5
Timing: 40-45*
Rotor: Stock Yellow
Fan: No (clip on heatsink, yes)

I was running 81/23 in my 4wd with 50 deg timing, which is close to what Randy posted. And yes, you will need a fan. I would recommend running your fan at full battery power (~8.4v) for the best possible cooling. The amount of air moved between 6v and 8.4 is huge.

I need to reshim my 13.5 spec-r. I have teflon shims for the sensor board side, but the pinion side seems to be about 4mm in diameter. I dont see motor shims on the tekin website, what is everyone using to shim the rotors. Also, my motor has 1 shim on each side of the rotor? Is that the "default"

Spare shims come in every Spec R box, they're under the foam with the sensor harness.

Well, I feel silly now, lol.

just wanting to confirm for a Gen 3 Mod motor, if a motor stutters / cuts out but when you pull the sensor setup it works (within reason of course), its most likely a bad sensor board (assuming the sensor wire and esc are good), correct? Or is there something else internal to the motor that could be going on?

Not 100% sure what you are saying, but in general stuttering or delay on throttle is a sensor issue of some sort. Can your ESC do non sensored mode? If so, try that and see if the issue changes or gets better. Make sure you disconnect the cable when doing this.

I just want to confirm its a board issue versus something else that would need to be looked at as well, assuming the sensor on the ESC is fine and the sensor wire is fine. The ESC can do both modes and the motor works basically in sensorless mode.

All you can do is troubleshoot. Try a new sensor wire, try a different sensor board and/or try a different ESC.

Yes, you are on the right track for troubleshooting. If you look closely at the esc, the last 3 LEDs (far right, labeled TP, MT, and VC) will be lit dimly to show what the sensors are reading. As you spin the motor, those 3 LEDs will cycle as the corresponding hall sensors read the rotor position. If one of them isn't lighting up, you definitely have an issue.

You don't even have to wire up a motor to test it. Just plug in the sensor port, power up the speed control, and spin the motor. I've tested other peoples motors while they were still in their car. Just don't hit the throttle!

Hey Randy,

Sorry to take so long to get back to you and Krio. You guys have been great to help my get my car rocking. Today, I shaved a consistent two-tenths of a second of my lap times by adding adjustable rear arms and lowering my ride height. Race results don't show it, but my car is now one of the fastest in 13.5. 1st and 3rd were mods that we turned down because we were short people. I traded paint too much and took 4th.

Anyways, a data file is long over due. Here's mine from tonight. Can you please take a look and recommend changes (if any)?

Spec-R
Yellow Rotor
Timing 45 (read from end bell)
Pinion 19
Spur 81
Temperature 150F

Futaba Radio 4PV
Expo -25
EPA 110

RS Gen2
Blinky mode

Also, I used the data logger, RPM and FDR to calculate the top end speed which made the Spec-R faster than RPM (in blinky mode). It's been great having access to this info. Although, I find the data logger tends to error often if I don't clear the data before the my run. Bluetooth connectivity can be finicky with my Samsung S8. Also, the app looks weird on Windows 10 and tries to save data files in to the Program Files directory instead of my user folder. Also, I've updated the app and firmware to the latest.

Besides the quirks, it works wonderfully. I easily gained 1000RPM using it.

Thanks again for all the help.

In general when the larger bottom bearing is seated properly, using a caliper, how "wide" should the endplate to the end of the bearing protruding should it be (6mm, etc). Reason I ask is I had a buddy whose 7.5T he was looking to chuck as it was overheating. He had basically no play and from what I can tell the bearing was sitting up pretty high compared to mine. Got it seated but figured be good to know the proper "width" it should be.

Hello,

I just ordered the RC10T6.1 Kit and will start racing for the first time. My local track is a high bite clay track with a lot of turns and just one long straight away. Since i'm new to the racing part of the hobby, what motor is recommended here, the Gen 3 or Gen 3 Spec-R? What gearing is recommended for this kit? I don't know if this is needed, but I will be running the RSX Pro.

Thanks!

Welcome to the racing scene! A 2wd truck was my first race vehicle as well. I don't see it mentioned, but I assume you are looking for a spec class motor like 17.5 or 13.5? I would go with the Spec-R motor, but you'd be fine either way for a long time. They just require different timing and gearing setups to make the most power which we can definitely help with once you make a selection. If this is an open/mod class, I would go with a regular 10.5 Gen3. Good smooth power that will run nice and cool.