The ARA311171 is Arrma's factory motor screw set — two M3 x 11.5mm screws with two shim washers, the hardware that clamps the motor to its mount. It fits eleven vehicles across the 223S, MEGA and 4S platforms in 1/10 and 1/8 scale.

These aren't generic fasteners. The head is oversized for a secure clamp against the motor face, low profile for clearance around the mount, and takes a 3mm hex for better torque transfer than a smaller drive would give. The shim washers set correct clamping across the mount slots.

Motor screws work harder than most hardware on the car. They hold the motor against constant vibration, and they come out again every time you adjust gear mesh or change a pinion — which is exactly the pattern that rounds out a hex socket. A stripped motor screw turns a five-minute pinion swap into a drilling job, so a spare pair on the shelf is worth having before you need it.

Features

• Large head design for a secure motor fit
• Low profile for extra clearance around the motor mount
• 3mm hex drive for greater torque transfer
• Precision manufactured for accurate fit
• Shim washers included to set correct clamping

Specifications

Thread: M3 (3mm)
Length: 11.5mm
Drive: 3mm hex
Quantity: 2 screws, 2 shim washers

Also written as 3x11.5mm, M3 x 11.5 or M3x11.5.

Fits

• Arrma 1/10 Big Rock 223S 4X4 RTR Brushless Monster Truck (ARA4312V4)
• Arrma 1/10 Granite 223S 4X4 RTR Brushless Monster Truck (ARA4302V4)
• Arrma 1/10 Granite MEGA 665 4X4 RTR Brushed Monster Truck (ARA4202V4)
• Arrma 1/10 Kraton 4S 4X4 RTR Brushless Speed Truck (ARA4408V2)
• Arrma 1/10 Outcast 4S 4X4 RTR Brushless Stunt Truck (ARA4410V2)
• Arrma 1/10 Senton 223S DSC 4X4 RTR Brushless Short Course Truck (ARA4303V4)
• Arrma 1/10 Vorteks 223S 4X4 RTR Brushless Stadium Truck (ARA4305V4)
• Arrma 1/8 Infraction 223S DSC 4X4 RTR Brushless All-Road Street Bash Truck (ARA4315V4)
• Arrma 1/8 Mojave 4S 4X4 RTR Brushless Desert Truck (ARA4404)
• Arrma 1/8 Typhon 223S 4X4 RTR Brushless Buggy (ARA4306V4)
• Arrma 1/8 Typhon MEGA 665 4X4 RTR Brushed Buggy (ARA4206V4)

Kraton and Outcast are the V2 models. This is a purpose-made motor screw with a specific head profile — a standard M3 cap head of similar length is not a substitute.

Includes

2 x M3 x 11.5mm Motor Screw
2 x Shim Washer