BENGALURU : Indian two-wheeler vehicle maker Hero Motocorp Ltd said on Friday it would invest up to 4.20 billion rupees ($56.66 million) in electric vehicle (EV) start-up Ather Energy as it looks to expand its presence in the green mobility space. The company, which held 34.8per cent in Ather Energy prior to the investment, said its new stake in the startup would be determined after Ather's funding round completes.