Screw Drivers Gear Guide
Master gear ratios and build efficient transmissions for any vehicle.
Gear System in Screw Drivers
Gears are the mechanical link between your engine and your wheels. They determine how engine power translates into motion — specifically, how much torque reaches the wheels and how fast they spin. A well-designed gear chain can make a modest engine feel powerful, while a poorly matched setup can leave even the strongest engine struggling. This guide covers every gear type in Screw Drivers, explains how gear ratios work, and provides practical examples for building effective transmissions.
Gear Types Catalog
Screw Drivers offers several gear types, each serving a specific purpose in your drivetrain.
Small Gear
The small gear is the fastest-spinning gear in the standard lineup. It has few teeth, which means it rotates quickly relative to the driving gear. Small gears are used for high-speed output in a gear chain. When paired with a large gear, they create a high-ratio setup that multiplies speed at the cost of torque.
Medium Gear
The medium gear is the all-around balanced option. It provides a moderate speed increase or decrease depending on its position in the gear chain. Most beginner builds use medium gears because they offer a good compromise between acceleration and top speed without requiring precise tuning.
Large Gear
The large gear has the most teeth among the standard gears. It rotates slowly but delivers significantly more torque than smaller gears. Large gears are essential for heavy builds, off-road vehicles, and any machine that needs strong low-end power to get moving.
Corner Gear
Corner gears allow you to transfer rotation around a 90-degree angle. This is critical for complex drivetrain layouts where the engine and wheels are not aligned on the same axis. Without corner gears, you would be limited to straight-line power delivery, severely restricting build creativity.
Plate Gear
Plate gears are flat, wide gears that provide a large contact surface. They are useful for distributing power across a wider area and can be integrated into the structural design of your vehicle. Plate gears are often used in custom transmission housings.
Worm Gear
The worm gear is a specialized component that converts rotational motion into linear motion, or changes the axis of rotation by 90 degrees with a high reduction ratio. Worm gears are self-locking, which means they prevent backdriving — the output cannot turn the input. This property is useful for creating mechanisms that hold their position without continuous power, such as adjustable wings or deployable ramps.
Planetary Gear
The planetary gear is the most unique gear in Screw Drivers. It features a fixed 1:2.3 ratio and uses a compact internal design with a sun gear, planet gears, and a ring gear. The planetary gear provides a significant speed multiplier in a small package, making it ideal for builds where space is limited but high output speed is required. Its internal construction also distributes load across multiple contact points, making it more durable than a single meshing gear pair.
The 1:2.3 ratio means the output shaft spins 2.3 times for every rotation of the input. This is a substantial speed increase, so pair it with adequate torque from your engine to avoid stalling.
How Gear Ratios Work
A gear ratio is determined by the number of teeth on the driven gear divided by the number of teeth on the driving gear. In Screw Drivers, this translates directly to the relationship between engine RPM and wheel RPM.
- Large driving gear to small driven gear — The output spins faster than the input. This is an overdrive ratio, increasing top speed but reducing torque at the wheels.
- Small driving gear to large driven gear — The output spins slower than the input. This is a reduction ratio, increasing torque at the wheels but reducing top speed.
Most vehicles benefit from a multi-stage gear chain that starts with a reduction for strong acceleration and shifts to overdrive for high top speed. The exact ratios depend on your engine, wheel size, and the track you are racing on.
Practical Gear Chain Examples
Beginner Build (Balanced)
Engine output connects to a medium gear, which meshes with another medium gear of the same size (1:1 ratio), then transfers to a large gear driving a small gear on the axle. This gives a moderate speed increase with good torque for getting off the line.
Speed Build (High Top Speed)
Engine output connects to a large gear, which drives a small gear (high ratio). A second stage uses a planetary gear (1:2.3) for additional speed multiplication. This setup maxes out top speed but sacrifices low-end torque. Only use this on flat, paved tracks where you can maintain momentum.
Off-Road Build (Maximum Torque)
Engine output connects to a small gear, which drives a large gear (low ratio for torque multiplication). A second large gear on the same shaft drives another large gear on the rear axle. This gives tremendous wheel torque for climbing hills and powering through mud, at the cost of a low top speed.
Custom Transmission with Corner Gears
When your engine and wheels are not on the same axis, use corner gears to redirect power flow. For example, a transverse-mounted engine can use a corner gear to send power longitudinally to the rear wheels. This layout is common in mid-engine sports car designs.
Tips for Gear Tuning
- Test frequently. Use the N key to switch between build and driving modes to test your gear ratios on the track. Small adjustments to gear sizes make a big difference.
- Watch the stats overlay. Press X in build mode to see structural information. Make sure your gear chain is fully connected and there are no gaps.
- Match gears to wheels. Large wheels need more torque to spin, so use lower gear ratios. Small wheels can use higher ratios for more speed.
- Planetary gears are space-efficient. Use them when you need a big ratio change in a tight build.
Related Pages
- Gear Transmissions Guide — Deep dive into transmission design
- Transmission Build Guide — Step-by-step transmission builds
- Parts Hub — Overview of all part categories
- Engines — Matching engines to gear ratios
- Wheels — How wheel size affects gearing
Frequently Asked Questions
Quick answers to the most common questions.
What does the planetary gear do in Screw Drivers?
The planetary gear has a fixed 1:2.3 ratio, meaning the output spins 2.3 times per input rotation. It provides a significant speed increase in a compact package, making it ideal for space-limited builds.
How do I build a transmission in Screw Drivers?
Connect your engine to a driving gear, then mesh it with a driven gear of a different size. Use multiple stages for bigger ratio changes. Add corner gears to redirect power when the engine and wheels are not aligned.
What gear ratio is best for speed?
For maximum top speed, use a large driving gear paired with a small driven gear, optionally followed by a planetary gear for additional multiplication. This works best on flat, paved tracks.
What gear ratio is best for off-road?
For off-road builds, use a small driving gear paired with a large driven gear to multiply torque. This gives your wheels more force to power through dirt, mud, and steep hills at the cost of top speed.