The rising differences between the two partners gradually emerged as an irritant. Differences had been brewing for a few years before the split over a variety of issues, ranging from Honda's reluctance to fully and freely share technology with Hero (despite a 10-year technology tie-up that expired in 2014) as well as Indian partner's uneasiness over high royalty payouts to the Japanese company. Another major irritant for Honda was the refusal of Hero Honda (mainly managed by the Munjal family) to merge the company's spare parts business with Honda's new fully owned subsidiary, HMSI.