[2] In 1980 Stappert took the role of Sporting Director and became responsible for BMW F1 programme, resulting in Nelson Piquet winning the 1983 F1 World Championship with the BMW-powered Brabham.
[3] He created a highly competitive team signing former Anton Mang's mechanic Franz-Josef "Sepp" Schlögl as technical director and starting a long-term relationship with Honda Racing Corporation to receive factory-spec NSR250s.
Over the years the HB team won many races with riders like Reinhold Roth, Helmut Bradl and Ralf Waldmann but never achieved the world title, finishing as runner-up four times (1987, 1989, 1991 and 1996).
In 2006 Stappert managed the KTM Junior Team in the 125cc class with Stefan Bradl as rider.
Stappert died in a hospital in Munich on October 17, 2008 having never recovered full consciousness since a heart attack in June.