Hero MotoCorp Ltd. on Friday said its July sales rose 21% on year to 449,755 units, the highest monthly growth in over a year, driven by strong performance in both domestic and export markets.Domestic sales rose 19% on year to 412,397 units, while exports surged 67% to 37,358 units. The company sold 400,615 motorcycles in July, up 18% on year, and 49,140 scooters, a 64% rise from the year-ago period.