How to Upgrade Your ARRMA 6S Motor and ESC (Step-by-Step)
Upgrading your ARRMA's motor and ESC is the biggest performance gain you can make. Here's exactly how to do it.
Watch the Tutorial
What You'll Need
- 1Phillips and hex screwdrivers
- 2Hex key set (metric)
- 3Soldering iron and solder
- 4Heat shrink tubing
- 5Zip ties
- 6Threadlocker (blue Loctite)
- 7Motor mount screws (usually included with motor)
Step-by-Step Guide
Remove the body and disconnect the battery
Always start with the battery disconnected. Remove your body pins, set the body aside, and disconnect your battery from the ESC. Double-check that no power is connected before proceeding.
💡 Tip: Take photos of your stock wiring setup before removing anything — it's easy to forget where things go.
Remove the stock ESC
Locate your stock ARRMA ESC (usually Spektrum Firma or similar). Unplug all connections — motor wires (3 bullet connectors), battery lead, receiver wire, and any fan connections. Note which motor wire goes to which ESC terminal. Unscrew the ESC mount and remove it from the chassis.
Remove the stock motor
Locate the motor — usually secured by 2-3 hex bolts on the motor mount. Remove the pinion gear (small gear on motor shaft) by loosening the set screw. Remove the motor mounting bolts and slide the motor out. Keep track of all hardware.
Install the new motor
Slide your new motor into the motor mount. Apply a small amount of blue Loctite to the mounting bolts and tighten them snugly — don't overtighten. Install the pinion gear on the new motor shaft, ensuring the set screw sits in the flat spot on the shaft. Set the mesh between pinion and spur gear with a business card's thickness of gap — tight enough not to skip, loose enough not to bind.
💡 Tip: Getting the gear mesh right is critical. Too tight causes heat and wear. Too loose causes skipping under load.
Install the new ESC
Mount your new ESC to the chassis — most aftermarket ESCs include mounting hardware. Connect the three motor wires to the ESC. The phase order determines motor direction. Connect them in any order initially and test rotation direction before final assembly. Connect the battery lead and receiver wire according to your ESC's manual.
Program the ESC
Most aftermarket ESCs (Castle, Hobbywing) require programming before first use. Connect to the ESC's programming software via USB, or use the button programming sequence in the manual. Set your battery type (LiPo), cell count, cutoff voltage, drag brake, and timing to match your setup. Castle Link and Hobbywing's app make this straightforward.
💡 Tip: Set your low-voltage cutoff correctly for your battery. This protects your LiPo from over-discharge.
Test and adjust
With everything connected, power up and test motor direction on the bench. If the motor spins backwards, swap any two of the three motor phase wires. Test all controls, check that braking works, and do a low-speed test run before going full throttle. Check for heat in the motor and ESC after the first run — some warmth is normal, hot is not.
Frequently Asked Questions
Do I need to re-gear after upgrading my motor?
Possibly. Higher kV motors often run better with a smaller pinion to keep temperatures down. Start with the stock pinion and monitor heat — if the motor or ESC runs hot, go down in pinion size.
Will an ESC/motor upgrade void my warranty?
Yes, typically. Aftermarket electronics are a modification and ARRMA won't cover damage caused by non-OEM parts. Factor this into your decision.
What's the difference between Castle and Hobbywing?
Castle Creations is known for bulletproof reliability and excellent software via Castle Link. Hobbywing delivers excellent performance at a slightly lower price point. Both are significantly better than stock ARRMA electronics.
Gear for This Guide
Castle Creations Sidewinder 8th ESC + 1515-2200Kv Motor Combo
Best drop-in combo for reliability. Castle Creations builds the most trusted ESCs in the hobby.
Check Price on Amazon →
Hobbywing XR8 Plus G2s ESC + Xerun 4268 1900KV Motor Combo
Best performance combo for the money. Hobbywing's XR8 Plus G2s delivers exceptional punch and runs cool.
Check Price on Amazon →