The core of the system works on a Stirling engine design, which incorporates four pistons and a ' wobble yoke '.
If you have a gas leak, if the pistons don't quite fit, if the bolts aren't tightened, or if the wheels are not on properly you're likely to crash when you get up to speed.
The belt cycles through the gun automatically using internal pistons.
Lego Technic creates more advanced, complex designs with moving parts like pistons, gears, and working motors.
This is when the friction between the pistons and the cylinders of your engine overheat so much that the engine completely breaks down and will require a complete rebuild to get it running again.
