3/32 INLINE soft plastic Gear 25t Orange

The NSR 3/32 25-tooth inline crown that fine-tunes your transmission to the millimetre

NSR is one of the benchmark brands in the world of competitive slot racing, and its line of soft plastic gears is proof of that. The crown NSR6325AL is made from soft orange plastic, which makes it easy to identify within the parts kit and, above all, guarantees smooth, quiet engagement with less wear on the pinion.

Main features

• Type: Inline crown (the motor is perpendicular to the rear axle, in line with the car, lowering the centre of gravity).
• Pitch: 3/32 — a widely used competition standard in NSR categories and club circuits.
• Number of teeth: 25t.
• Material: Soft plastic, orange colour.
• Reference: NSR6325AL.

Function and performance

In an inline configuration, the motor is placed longitudinally relative to the rear axle. This arrangement lowers the car's centre of gravity and improves traction in fast corners, making it the preferred option in many NSR competition chassis and in regulated club categories.

The soft material better absorbs the micro-vibrations from the motor and reduces transmission noise, two factors that make a difference in a long race between a transmission that endures and one that degrades. The orange colour is not just aesthetic: NSR colour codes its crowns to facilitate quick identification of the number of teeth without the need to count each time.

Compatibility and installation

This crown is compatible with NSR chassis that accept inline configuration and 3/32 pitch. Before installing it, check that your motor's pinion also has a 3/32 pitch to ensure correct engagement. The number of teeth on the crown (25t) combined with that of the pinion determines the final gear ratio, which directly affects the top speed and acceleration of the car.

Installation requires correctly adjusting the gap between the crown and pinion: too tight generates heat and premature wear; too loose causes power loss and noise. NSR recommends using its setup tools to achieve the optimal point.

Common mistakes

• Mixing different pitches (for example, a 48p pinion with a 3/32 crown): the teeth do not engage correctly and the transmission fails.
• Not checking the motor alignment before securing the crown, leading to asymmetric wear.
• Reusing a soft crown with visible signs of wear: soft plastic is economical and should be replaced regularly in competition cars.

Ideal for…

Club racers competing in regulated categories with NSR inline chassis, as well as enthusiasts preparing cars for technical circuits where weight balance and smooth transmission are priorities. It is also a common choice for those experimenting with different gear ratios in search of the optimal setup for each track.

Frequently asked questions

What is the difference between an inline crown and a sidewinder?

In the inline configuration, the motor is positioned perpendicular to the rear axle (in line with the car), which lowers the centre of gravity. In the sidewinder configuration, the motor runs parallel to the rear axle (transversely). Each arrangement offers distinct dynamic behaviour and requires a specific crown for each type of installation.

What does the orange colour code on NSR crowns mean?

NSR uses a colour coding system on its plastic crowns to quickly identify the number of teeth. Orange corresponds to the 25-tooth crown in the soft range. This speeds up work at the preparation bench, especially when handling multiple gear ratios at once.

Can I use this crown with any NSR inline motor?

It can be used with motors installed in inline configuration whose pinion is 3/32 pitch. It is essential that the pitch of the pinion matches that of the crown. Check your motor's specifications before installation.

When should I change the soft crown?

Soft plastic is more susceptible to wear than aluminium crowns. It is advisable to check it periodically and replace it when worn or deformed teeth are noticed, or when the sound of the transmission changes tone. In regular competition cars, a check after each race day is a good practice.

What gear ratio does a 25-tooth crown give me?

The gear ratio is calculated by dividing the teeth of the crown by those of the pinion. With 25 teeth on the crown, the final ratio depends on the pinion you use: a 9-tooth pinion gives a ratio of approximately 2.78:1. A higher ratio provides more acceleration and less top speed; a lower ratio gives more top speed and less acceleration. Experiment with different pinions to adapt the setup to each circuit.

The NSR6325AL is a 25-tooth inline gear for 3/32 axle, made in soft plastic and identified by its orange colour. Designed for inline motor configurations in 1/32 slot car racing, it delivers smooth and quiet transmission with reduced wear. A go-to choice for club racers and slot car enthusiasts looking to fine-tune their drivetrain setup with reliable NSR quality parts.