Road grime does not require a forceful jet of water. Let the engine and exhaust cool first, then rinse away loose dirt with cool water. Clean the surfaces with a soft sponge or cloth and a mild cleaner suitable for motorcycles; harsh solvents can damage paint, plastics and metal finishes.
A high-pressure spray can drive water into sensitive areas and damage components. Keep water away from exhaust openings and electrical connections. Rinse off cleaner thoroughly and dry the motorcycle. If the bike has a chain drive, lubricate the chain after washing and drying in line with its maintenance instructions.
Check the brakes before returning to traffic. They may feel less responsive immediately after washing, so brake gently at first and allow more stopping distance. Cleaning also provides a chance to look closely for damage or leaks that road dirt may have concealed.