27Z brass insert crown gear

Slot.it 27Z Crown Gear for Inline: Direct and Precise Transmission in Bronze Finish

The SIGI27-BZ crown gear from Slot.it is a transmission component designed for inline motor setups, where the motor is positioned longitudinally relative to the rear axle, lowering the car's centre of gravity. With 27 teeth and manufactured for a 2.38 mm axle, it fits directly into the Slot.it mechanical set range without the need for adaptations.

The bronze finish is not just aesthetic: it facilitates quick identification of the tooth count among the various references in the range and provides a machined surface that promotes smooth engagement with the motor pinion.

Main Features

• Teeth: 27Z
• Axle Diameter: 2.38 mm
• Configuration: inline motor (longitudinal to the rear axle)
• Finish: bronze
• Brand: Slot.it
• Reference: SIGI27-BZ

Function and Performance

In an inline configuration, the gear ratio between the pinion and crown gear directly determines the car's behaviour: acceleration, top speed, and cornering response. A 27-tooth crown gear offers a balance between acceleration and top speed, suitable for circuits with a mix of curves and medium straights. By adjusting the pinion in combination with this crown gear, the gear ratio can be fine-tuned according to the track's requirements.

Slot.it's manufacturing ensures very tight tolerances, resulting in a rotation without play or vibrations that could affect lap consistency.

Compatibility and Installation

This crown gear is designed for Slot.it inline transmission sets with a 2.38 mm axle, the most common standard in the brand's chassis. It is compatible with Slot.it inline motors and mounts directly onto the rear axle. Before securing it permanently, it is advisable to check that the backlash (play between pinion and crown gear) is correct: not too tight, which generates friction and heat, nor too loose, which introduces imprecision in the transmission.

Common Errors When Installing Inline Crown Gears

• Not checking lateral alignment: the crown gear must be perfectly aligned with the motor pinion to avoid premature wear.
• Excessive pressure when fitting onto the axle: forced installation can slightly deform the part. It is recommended to use a specific installation tool.
• Confusing inline with sidewinder: this crown gear is for inline motors. In a sidewinder setup, the motor runs parallel to the rear axle and different profile crown gears are used.

Frequently Asked Questions

Is this crown gear compatible with sidewinder chassis?

No. The reference SIGI27-BZ is designed for inline configurations, where the motor is oriented longitudinally to the rear axle. For sidewinder setups, Slot.it offers specific crown gears with different profiles and tooth counts.

What pinion works well with a 27-tooth crown gear?

It depends on the circuit and the motor, but pinions ranging from 9 to 11 teeth are the most common with a 27Z crown gear. Longer ratios (small pinion / large crown) provide more top speed; shorter ratios offer better acceleration. We recommend testing on track to find the optimal point according to the layout.

What axle diameter is it designed for?

For a 2.38 mm axle, which is the most widespread standard in Slot.it transmission sets. Always check your axle diameter before ordering the crown gear.

Is it necessary to lubricate the crown gear?

A thin layer of specific slot transmission lubricant at the contact point between the pinion and crown gear extends the lifespan of both parts and improves transmission efficiency. Do not overdo the amount: excess lubricant can attract dirt and affect tyre grip.

Can I use this crown gear on Ninco or Scalextric track?

The crown gear is an internal part of the car, independent of the type of track. You can use it on any track, as long as the chassis and the car's mechanics are compatible with the inline setup and the 2.38 mm axle.

The Slot.it SIGI27-BZ is a 27-tooth inline crown gear in bronze finish, designed for 2.38 mm axle setups. A precise and reliable transmission component for inline motor configurations, widely used in club racing and home slot car setups. Compatible with the full Slot.it inline drivetrain range, it delivers consistent gear mesh and low friction for lap-time consistency.