Alert was an English motorcycle manufactured by Smith & Molesworth at Coventry between 1903 and 1906. The bikes were powered by 2.35, 2.75 and 3.25 bhp Saroléa engines.
References
12Tragatsch, Erwin; Ash, Kevin (2000). The New Illustrated Encyclopedia of Motorcycles. London: Quantum Publishing. p.560. ISBN1-86160-342-8.