1 Prepare for safe work
Position the bicycle stably, clean the work area, and photograph the arrangement of washers and cables. Turn off an electric bike or scooter and remove the battery if it is designed to be detached.
⚠ Warning: Do not ride with a loose wheel, handlebar, broken spoke, faulty brake, or damaged frame. Have safety-critical parts checked in a workshop.
2 Determine the exact symptom
Verify that the training wheels and brackets fit the bicycle and that the rear axle has enough thread for secure fastening.
3 Check the most common cause
Position both wheels equally, slightly off the ground when the bike is upright. The bike should lean slightly, but must not tip over.
4 Resolve the cause without improvisation
Tighten the fasteners, check the brakes, and practice on a flat surface under supervision. Gradually increase the height as the child gains balance.
? Tip: Photograph the initial state and change only one thing at a time. This makes it easier to recognize what really solved the problem.
5 Assemble and test safely
Spin the wheels and drivetrain by hand, then do a slow test ride in an area without traffic. Steering, wheels, and brakes must operate completely predictably.