Many dirt biking enthusiasts often overlook the importance of cleaning their helmets, and not only their bikes. The way you wash a dirt bike helmet depends on whether it comes with a detachable liner or not. A removable liner is usually easy to clean, and you can just throw it with the rest of the laundry in a washing machine. The foam liner and the cheek pads can be washed, too, and they usually need a gentle warm cycle, so they do not lose their shape. The shell should be scrubbed with lukewarm water and a mild detergent to remove all traces of dirt. Wipe everything well and leave it to dry properly, before putting the helmet back together.