34t crown. Sidewinder M50 for 2.38mm axle O18.5mm with M2.5 screw.

The crown that fine-tunes your Sidewinder transmission with Scaleauto precision

The 34-tooth Sidewinder Crown M50 (ref. SC-1144R) from Scaleauto is a transmission component specifically designed for Sidewinder configurations, meaning the motor is positioned parallel to the rear axle. With 34 teeth, module 50 (M50), an outer diameter of 18.5 mm, and a 2.38 mm axle hole, it fits the most common specifications for club and competition setups on Sport track.

Features and function

• Number of teeth: 34
• Module: M50
• Outer diameter: Ø18.5 mm
• Axle diameter: 2.38 mm
• Fixing: M2.5 screw
• Configuration: Sidewinder (motor parallel to the rear axle)
• Brand: Scaleauto
• Reference: SC-1144R

Function and performance

In a slot car transmission, the crown gear is the component that receives the motion from the pinion attached to the motor shaft and transfers it to the rear axle. The resulting gear ratio — the number of teeth on the crown divided by the teeth on the pinion — directly determines the top speed and torque available at the wheel: a 34-tooth crown offers a balanced compromise between acceleration and speed, suitable for most medium-length club circuits.

The M50 module is the standard commonly used in 1/32 and 1/24 scale competitive slot racing, making it easy to pair with pinions from the same series. The fixing with an M2.5 screw ensures that the crown does not migrate laterally under vibration, which is critical when seeking consistency from lap to lap.

Compatibility and installation

This crown is designed for axles with a diameter of 2.38 mm, a common measurement in Scaleauto competition chassis and mounts. Before installation, it is advisable to check that the axle is properly aligned and that the lateral play with the pinion is minimal, allowing for smooth rotation without interference. The M2.5 screw should be tightened with the appropriate size Allen key, applying a small amount of thread locker if the assembly is to be subjected to intensive use.

For optimal performance, combine it with Scaleauto pinions from the same M50 family and ensure that the motor-crown-pinion alignment is precise: any angular deviation generates premature wear and loss of efficiency.

Ideal for…

• Slot car tuners in club categories with Sport track.
• Drivers looking to adjust the gear ratio without changing the pinion.
• Sidewinder setups in Scaleauto 1/32 scale chassis and mounts.
• Replacement of worn or damaged crowns while maintaining the original gear ratio.

Common mistakes to avoid

• Mixing modules: do not combine this M50 crown with pinions of a different module; the tooth profile does not fit and wear is immediate.
• Excessive tightening of the screw: this can deform the crown hub or mark the axle, making future disassembly difficult.
• Incorrect lateral play: too much play generates noise and loss of torque; too tight a fit causes overheating and wear.

Frequently asked questions

Which pinions is this M50 crown compatible with?

With any M50 module (module 0.5) pinion from the Scaleauto range or other brands that adhere to the same module. Always check that the module is identical to ensure proper meshing.

Is it valid for Inline or Anglewinder configurations?

This crown is specifically designed for Sidewinder setups, where the motor is parallel to the rear axle. In Inline or Anglewinder configurations, crowns with different gear geometry are used; consult the corresponding Scaleauto range.

What gear ratio do I get with this crown?

It depends on the pinion you use. For example, with an 11-tooth pinion, you get an approximate ratio of 3.09:1; with a 9-tooth pinion, 3.78:1. The higher the ratio, the more torque and lower top speed, and vice versa.

Can I use it on Scalextric or Ninco tracks (Universal track)?

The crown itself is independent of the type of track; what matters is that the chassis, motor, and axle are compatible. The SC-1144R crown works on any circuit as long as the car's mechanical assembly is prepared for it.

Do I need special tools for installation?

Only an Allen key of the appropriate size for the M2.5 screw is required, and optionally, a gap gauge or caliper to check the alignment of the transmission train. No specialized tools are needed.

The Scaleauto SC-1144R is a 34-tooth M50 crown gear for Sidewinder motor setups, designed for a 2.38mm axle and 18.5mm outer diameter, secured with an M2.5 grub screw. A precision slot car transmission part for 1/32 scale competitive and club racing, compatible with M50 pinions and Scaleauto Sport track axle systems.