14 Brass Pinion ø7.0mm for 2mm Shaft.

Transmission Precision: 14-Tooth Brass Pinion for 2 mm Axle

The pinion is one of the most critical components of the transmission in any slot car. One tooth more or less, a few tenths of a millimetre out of specification, and the engagement with the crown gear ceases to be smooth. That is why choosing the correct pinion makes the difference between a car that runs smoothly and one that loses efficiency with every metre of track.

Function and Performance

This Scaleauto pinion (SC-1097A70) features 14 teeth, an outer diameter of 7.0 mm, and is machined to fit 2 mm axles. The choice of brass as a material provides a combination of rigidity and machinability that is particularly suitable for transmissions that demand tight tolerances and controlled wear.

The number of teeth on the pinion, combined with the teeth of the crown gear it pairs with, determines the gear ratio of the car. With 14 teeth, a versatile configuration is achieved, suitable for both short and technical circuits where response is more important than top speed, and as a starting point for finer adjustments depending on the layout and the motor used.

Compatibility and Installation

This pinion is sized for 2 mm axles, the standard size in the vast majority of slot car setups in 1/32 and 1/24 scales. It is compatible with the usual transmission system in cars equipped with inline (motor in line with the rear axle) or sidewinder (motor transverse to the axle) configurations, provided that the module of the crown gear it is combined with is appropriate.

Before installation, it is advisable to verify that the module of the pinion matches that of the crown gear it will be paired with. Engagement between components of different modules causes vibrations, noise, and premature wear on both parts.

Installation and Preparation

For a correct fit on the axle, it is recommended to:

• Clean the axle of grease or dirt residues before mounting the pinion.
• Check the alignment with the crown gear to ensure centred engagement.
• Apply a minimal amount of specific slot transmission lubricant to the flanks of the teeth, without overdoing it to avoid attracting dust or dirt.
• Verify the backlash (clearance between pinion and crown gear): there should be a minimal play to prevent binding when hot, but it should not be excessive.

Common Mistakes

• Mixing different modules between pinion and crown gear: although they may fit physically, wear will be rapid and performance poor.
• Over-tightening the pinion securing screw on the axle, which can deform the inner bore and create eccentricity.
• Not checking the lateral alignment of the pinion with the crown gear before closing the chassis.

Frequently Asked Questions

Which crown gears is this 14-tooth pinion compatible with?

It depends on the module. It is essential that the pinion and crown gear share the same module for correct engagement. Scaleauto offers crown gears in different modules; consult the specifications of each crown gear before combining them with this pinion.

Why choose brass over other materials like plastic or harder metals?

Brass offers an interesting balance: it is more durable than plastic, can be machined with great precision, and has a favourable coefficient of friction. In combination with high-performance plastic crown gears, wear occurs in a controlled and predictable manner, facilitating maintenance.

How does the number of teeth on the pinion affect track behaviour?

A pinion with fewer teeth (and the same crown gear) offers higher top speed but less acceleration. With more teeth, the ratio shortens and corner exit is improved. With 14 teeth, it operates in an intermediate range, useful as a base configuration for subsequent adjustments depending on the layout.

Is any adhesive needed to secure the pinion to the axle?

It depends on the pinion's securing system. If it has a set screw, no adhesive is necessary. If the fit is by pressure, some preparers apply a drop of low-strength axle adhesive to prevent movement without hindering future disassembly.

Is this pinion suitable for 1/24 scale?

The pinion is compatible with 2 mm axles, a size present in both 1/32 and some 1/24 setups. The determining factor is the module and alignment with the crown gear of the specific car it will be mounted on.

The Scaleauto SC-1097A70 is a 14-tooth brass pinion gear with a 7.0 mm outer diameter, designed for 2 mm axles. An essential slot car transmission part for 1/32 and 1/24 scale builds, compatible with inline and sidewinder motor configurations. Ideal for club racers and hobbyists seeking precise gear ratios and consistent performance on the track.