Tank slap

Tank slap, an example of harmonics, is a dangerous and scary situation condition for motorcycle riders.

A Tank Slap can occur at any speed and is characterized by rapid and wild swings of the handlebars from hard-stop right to hard-stop left and back again. Tank slap happens when harmonic feedback is generated following the front tire hitting an imperfection on the road surface such as the slight bump at the end of your driveway.

With motorcycles being light, it is very easy for the front end of the motorcycle to lose contact with the road surface. When the front end makes contact again with the road surface and is not in line with the back tire, the front end reacts violently transferring the energy into oscillations of the handlebars.

The condition, in the hands of inexperienced riders, leads to a high-side crash.

It is recommended to maintain throttle position and let the oscillations diminish. The reason for this is to allow the motorcycle weight to reach equilibrium. Applying the front brakes or chopping the throttle, puts a forward bias of the front end which combined with oscillations, leads to a break in traction causing an accident.