Crown gear in line 30z

30-Tooth Inline Crown Gear for 2.38 mm Axle — Avant Slot AV20637

The 30z Inline Crown Gear from Avant Slot (ref. AV20637) is a specific transmission spare part for inline motor configurations, meaning those where the motor is aligned with the rear axle, with the crankshaft perpendicular to that axle. This type of mounting allows for a lower centre of gravity for the car and is common in setups aimed at both club competition and use on technical tracks.

Technical Specifications

• Number of Teeth: 30z
• Configuration: Inline (motor aligned with the rear axle)
• Compatible Axle Diameter: 2.38 mm
• Fixing System: M2.5 screw (included in the package)
• Brand: Avant Slot
• Reference: AV20637

Function and Performance

The crown gear is the gear that receives the motion from the pinion attached to the motor shaft and transmits it to the rear axle, largely determining the final gear ratio. With 30 teeth, this crown offers a favourable multiplication for achieving top speed on long straights when combined with pinions of fewer teeth, or a balance between acceleration and maximum speed depending on the chosen pinion.

The anchoring via M2.5 screw ensures a secure fixation without unwanted play, preventing vibrations and premature wear that can occur when the crown is not properly secured to the axle.

Compatibility and Installation

This crown is designed for axles with a 2.38 mm diameter, a widely used standard measurement in 1/32 scale slot racing. It is essential to verify that your axle has exactly that diameter before installation, as a loose crown on the axle compromises transmission and can damage both the part and the rest of the drivetrain.

For installation, it is recommended to:

1. Check the alignment between the pinion and crown before tightening the screw definitively.
2. Ensure there is no lateral rubbing with the chassis or the bracket.
3. Tighten the M2.5 screw with the appropriate tool, without over-torquing to avoid damaging the crown material.
4. Check the backlash (play between pinion and crown): too much play results in transmission loss; too little causes friction and heating.

Common Errors

• Confusing inline with sidewinder: in sidewinder, the motor is parallel to the rear axle (transversal); in inline, it is perpendicular (longitudinal). This crown is designed for inline mountings.
• Not checking the axle diameter: installing a crown on an axle of a different diameter causes eccentricity and vibrations.
• Forgetting the fixing screw: although included, it is advisable to keep it with the part if stored before installation.

Ideal for…

This crown fits into preparation and tuning projects for 1/32 scale slot cars with inline motor configurations, both for drivers looking to adjust the gear ratio according to the track and for those needing to replace a worn crown after intense competition sessions.

Frequently Asked Questions

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

The difference lies in the orientation of the motor relative to the rear axle. In an inline setup, the motor is in line with the axle (perpendicular to it), allowing for a lower centre of gravity. In sidewinder, the motor is parallel to the axle (transversal). Each configuration requires its own crown, so it is essential not to interchange them.

Is the M2.5 screw included?

Yes, according to the official Avant Slot description, the M2.5 fixing screw is included with the crown.

Which pinions is this crown compatible with?

The crown itself does not have a limitation for specific pinions beyond the requirement that the gear module must match. Avant Slot offers complementary pinions: check their catalogue to find the suitable combination based on the desired gear ratio.

Is it suitable for club racing?

Yes, as long as your championship regulations allow the use of aftermarket or brand-specific crowns. With 30 teeth, it is a versatile option for medium to long tracks.

Can I use it on axles with a diameter different from 2.38 mm?

It is not recommended. This crown is calibrated for a 2.38 mm axle. Forcing it onto an axle of a different diameter can cause eccentricity, accelerated wear, or even breakage of the part.

The Avant Slot AV20637 is a 30-tooth inline crown gear for 2.38 mm axles, secured with an M2.5 screw (included). Designed for inline motor configurations in 1/32 scale slot car racing, it delivers precise power transmission and easy installation. A reliable replacement part for club racing and workshop builds alike.