Gear ratios, gearboxes and car drivetrains explained
How do gears trade speed for strength, and how do real cars change gear, steer and grip? Each guide answers one question and gives you a free car build to test it.
10 guides
- Gears & cars
Universal joint speed chart: why a bent driveshaft speeds up and slows down
A reference chart for universal joint angles: how much a bent Technic-style driveshaft speeds up and slows down, and how two joints cancel the wobble.
- Gears & cars
Why two 2-speed gearboxes give only three speeds: range and splitter boxes explained
Gearboxes in a row multiply, so equal ratios repeat a speed. See it on a Technic-style three-speed car, then learn how truck range and splitter boxes avoid it.
- Gears & cars
Four-wheel drive explained: 4WD vs AWD, and when it actually helps
Answers to common four-wheel drive questions: what 4WD and AWD mean, why a centre differential matters, and why 4WD climbs better, with Technic-style builds.
- Gears & cars
Belts, chains or gears? A Technic-style lesson on moving power
A ready-to-run lesson: why belts and chains carry turning across a gap, why a crossed belt reverses it, and why a belt slips when a chain can’t.
- Gears & cars
What is torque? Feel the trade between speed and strength
Torque explained with a hand winch you can crank on screen, then four Technic-style builds that let you feel speed and strength trade places.
- Gears & cars
How to test steering and suspension on a Technic-style car
Use a turning-circle test and a one-wheel bump test to separate steering geometry, suspension travel and ground clearance on small builds.
- Gears & cars
How to test speed and torque with a two-speed gearbox
Build a small two-speed mechanism, count its wheel turns, then compare flat-floor speed and ramp climbing with a repeatable test.
- Gears & cars
Why won't a Technic-style car climb? Torque, grip and balance
Diagnose a climbing car by separating motor stall, tyre slip and tipping, then run a controlled ramp test using small Technic-style builds.
- Gears & cars
Pull-back car science experiment: a practical fair test
Build a pull-back car, then run a real fair test: how far does it go when you pull back further, add weight or change gears?
- Gears & cars
What is a differential? An explanation you can build
Why a car’s wheels need to turn at different speeds in a corner, and a push-along build that lets builders see a differential work.
Free builds for this topic
- ⚙️ Builds that teach gears and gear ratios (42)
- 🏎️ Car and vehicle builds (42)
- ↔️ Builds with working steering (18)
- 🔙 Pull-back car builds (10)