Don’t throw away old toothbrushes. Tying two together can solve many problems

Bicycle chains often have a mixture of engine oil and sand stuck to them, which not only increases the weight but also reduces the life of the chain. To clean them, tie two old toothbrushes together with tape so that the bristles of the brushes face each other. Then, place the bicycle chain between the two brushes and rotate the pedals. Now you can clean the chain easily.