36d crown M50 nylon for axle 2.38mm O17.5mm

Scaleauto SC-1156R Crown Gear: 36 Teeth M50 Nylon for 2.38 mm Axle

When your slot car's transmission needs renewal or adjustment, the choice of crown gear makes a difference. This crown gear from Scaleauto, reference SC-1156R, combines a tooth count of 36 teeth with module 50 and nylon material, offering a smooth and durable response in the drivetrain.

Technical Specifications

• Number of Teeth: 36
• Module: 50 (M50)
• Material: Nylon
• Axle Diameter: 2.38 mm
• Outer Diameter: 17.5 mm
• Fixing System: M2.5 Screw
• Brand: Scaleauto
• Reference: SC-1156R

Function and Performance

The crown gear is the key link between the motor pinion and the rear axle. Premature wear or excessive play in the transmission directly translates to a loss of top speed and an irregular response when accelerating. Nylon dampens vibrations better than steel or brass, reduces noise levels during operation, and is more tolerant of small misalignments between pinion and crown, which is common when working with adjustable mounts or in competition setups where the motor is frequently repositioned.

The 36-tooth on M50 ratio is one of the most versatile combinations in modern slot racing: it allows for balanced gear ratios by combining it with pinions of different tooth counts, adapting the car to both technical tracks with many slow corners and to ovals or high-speed layouts.

Compatibility and Installation

This crown gear is manufactured for axles with a 2.38 mm diameter — a standard measurement in a large part of the Scaleauto car range and in many Sport track competition platforms — with an outer diameter of 17.5 mm. The fixing is done using an M2.5 screw, ensuring a firm fit and repeatable adjustment with each disassembly, which is particularly appreciated by those working with various transmission configurations depending on the track.

Before installation, it is advisable to check the lateral alignment between the pinion and crown with a caliper or thickness gauge, ensuring that the flank play is the minimum necessary without applying pressure. Excessive pressure accelerates the wear of the nylon; too loose a fit causes rattling and jumping under hard acceleration.

Common Mistakes When Replacing the Crown Gear

• Confusing the module: M50 and M48 are not interchangeable even though they may look similar. Always check the module of the pinion used with your motor.
• Over-tightening the M2.5 fixing screw on the axle, which can deform the nylon housing and create eccentricity.
• Not cleaning the axle before installation: residues of lubricant or dirt hinder the correct seating and may cause the crown to rotate slightly on the axle under load.
• Mixing crown gears of different modules with the existing pinion without verifying gear compatibility.

Frequently Asked Questions

Is this crown gear compatible with standard open can motors?

Compatibility does not depend on the motor but on the pinion that the motor uses. You need to verify that the pinion is M50 for the gear mesh to be correct. The receiving axle is 2.38 mm, a common measurement in Scaleauto platforms and other manufacturers of Sport track spare parts.

What advantage does nylon have over aluminium or brass in a crown gear?

Nylon absorbs micro-vibrations from the transmission better, is quieter, and tolerates small misalignments without damaging the pinion. Conversely, it has a lower upper temperature and load limit compared to metal, but within the usual operating range of slot racing, it is completely sufficient and lasts many sessions without noticeable wear.

Can I use this crown gear in Sidewinder and Inline configurations?

Yes. The crown gear itself is not conditioned by the motor configuration. Whether in a Sidewinder setup — with the motor parallel to the rear axle — or in an Inline setup — with the motor in line with the car — the relevant factor is that the pinion module is M50 and the axle is 2.38 mm.

What pinions work well with it for a typical club transmission ratio?

With 36 teeth on the crown gear, pinions with between 9 and 12 teeth M50 offer common transmission ratios in club competition. The exact choice depends on the motor, the track, and the type of race: for fast layouts, the pinion is usually increased; for technical circuits, it is decreased.

Is the M2.5 screw included in the package?

The product description states that the fixing is done using an M2.5 screw, but it does not specify whether it is included in the package. We recommend checking directly with our team before placing your order if you need the screw.

The Scaleauto SC-1156R is a 36-tooth M50 nylon crown gear designed for 2.38 mm axles with a 17.5 mm outer diameter and M2.5 screw fixing. A precise and reliable slot car transmission part, ideal for Sport track racing and club competition builds requiring consistent gear mesh and smooth power delivery.