Repeat Robotics Scalar Antweight Weapon Motor
Built for Serious Antweight Weapons
The Repeat Robotics Scalar antweight weapon motor is the 2305 2400KV brushless motor spec’d by Repeat Robotics for the Scalar combat robot kit. Redesigned from the ground up for belt-driven weapon systems, it delivers excellent power density on 2–4S LiPo with a 5mm D-flat shaft, screw-retained for reliable engagement — no c-clips to fail under shock loads. A drop-in replacement for your Scalar Kit, or for your own design!
$22.50
Available on backorder
The Scalar’s Spec’d Weapon Motor
The Repeat Robotics Scalar antweight weapon motor is the 2305 2400KV brushless motor designed specifically for the Scalar combat robot kit. Repeat Robotics redesigned this motor from the ground up for belt-driven antweight weapon applications — not a repurposed drone motor, but a purpose-built combat weapon drive. It runs on 2–4S LiPo and delivers the power density and reliability that competitive antweight builders need.
Engineered for Combat
At 2400KV on a 3S pack you’re looking at roughly 25,200 no-load RPM — plenty of weapon speed for horizontal or vertical spinner configurations. The 5mm output shaft comes with a D-flat already installed for positive pulley engagement, and the shaft is retained with a screw rather than c-clips. C-clips are a known failure point under the shock loads of combat; the screw-retained design eliminates that risk entirely. M5 threads on the shaft accept a standard locknut for secure weapon hub retention.
Mounting and Fit
The motor mounts via 4× M3 tapped holes on a 16mm bolt circle, 3mm deep — the same pattern used across the Scalar weapon system. Body diameter is 28.20mm with a compact 16.0mm height, keeping weight low and CG tight in your chassis. At 30.2g with full-length wires, it fits comfortably within antweight weight budgets. Works directly with the Repeat Robotics Scalar Weapon Pulley and Scalar Weapon Belt 267-3M-05.
Works Beyond the Scalar
While spec’d for the Scalar kit, the 2305 2400KV is a strong choice for any custom antweight weapon drive. The compact form factor, robust shaft retention, and 2–4S flexibility make it adaptable to a wide range of 1lb combat designs. A 3D model is available on GrabCAD for builders who want to design around it.
Safety Warning:
Spinning weapons generate extreme kinetic energy. Always engage a weapon lock and test only within a secure arena or test box. Never operate a spinning weapon in an unsecured area.
Features
- Spec’d by Repeat Robotics for the Scalar antweight combat robot kit
- 2400KV on 2–4S LiPo — flexible power for horizontal or vertical spinners
- 5mm D-flat shaft with screw retention — no c-clips to fail under shock loads
- M5 locknut threads for secure weapon hub and pulley retention
- 4× M3 mounting holes on 16mm bolt circle — matches Scalar weapon system pattern
- Compact 28.2mm bell diameter keeps weight and CG low in the chassis
- 30.2g with full-length wires — fits comfortably in antweight weight budgets
- Purpose-built for combat — not a repurposed drone motor
Specifications
| Specification | Details |
|---|---|
| Motor Type | Brushless outrunner weapon motor |
| KV Rating | 2400KV |
| Voltage Range | 2–4S LiPo (7.4–14.8V) |
| Diameter | 1.11in (28.2mm) |
| Height | 0.63in (16.0mm) |
| Shaft Diameter | 5mm with D-flat installed |
| Exposed Shaft Length | 0.61in (15.4mm) |
| Shaft Retention | Screw-retained — no c-clips |
| Shaft Thread | M5 for locknut |
| Mounting Pattern | 4× M3 tapped on 16mm bolt circle, 3mm deep |
| Weight | 1.07oz (30.2g) with full-length wires |
Frequently Asked Questions
What does “2305” mean — is that the motor size?
Yes and no — it depends on the motor family. For FPV-style outrunner motors like this one, the number refers to the stator dimensions: 23mm stator diameter × 5mm stator height. The stator is the stationary inner core with the copper windings. The outer bell (the part that actually spins) is larger — 28.2mm in diameter on this motor. So don’t be surprised when your calipers read 28mm, not 23mm. For older can-style motors like the D2822, the convention is reversed and the number refers to the overall body dimensions. Two different motor families, two different conventions — it’s a quirk of how the hobby evolved.
What ESC do I need for this motor?
The Scalar kit uses the ReadyToSky 35A BLHeli_S Brushless Weapon ESC, which is spec’d to match this motor on 3S power. If you’re running a custom build, any BLHeli_S or AM32 compatible ESC rated for your cell count and current draw will work.
What pulley and belt does this motor use?
The Scalar weapon system uses the Repeat Robotics Scalar Weapon Pulley and the Scalar Weapon Belt 267-3M-05. The 5mm D-flat shaft interfaces directly with the pulley — no adapter needed.
Why screw retention instead of c-clips?
C-clips are a known failure point in combat robotics. Under the repeated shock loads of weapon impacts, c-clips can pop off or deform, causing the shaft to walk out of position. The screw-retained design on the 2305 eliminates that failure mode entirely — the shaft stays put no matter what the weapon takes.
You may also like…
-
Repeat Robotics Scalar Combat Robot Kit
$249.00 Select options This product has multiple variants. The options may be chosen on the product page -
Repeat Robotics Scalar Aluminum Weapon Hub
$20.00 Add to cart -
Repeat Robotics Scalar Weapon Belt 267-3M-05
$4.00 Add to cart -
Repeat Robotics Scalar Weapon Pulley
$6.00 Add to cart -
Repeat Robotics Scalar Weapon Kit
$25.00 Add to cart
