Sambuy's deputy Siobhan Curtin will replace him when he leaves in January. She will report to managing director Massimo Mirosi.
The announcement follows Piaggio's appointment last month of Bates UK to handle its advertising account (Marketing, November 14).
Piaggio's first advertising through Bates will launch in the early part of 2003.
The company had intended to advertise on London Transport sites including Adshel. However, because the ads will position scooters as an alternative to public transport, media-owner Clear Channel will not allow it to use that medium.
Sambuy joined Piaggio UK in 1999. He was previously brand manager for its Gilera scooters in Italy.
The company, which owns the Piaggio, Vespa and Gilera brands, has seen sales rocket from 600 in 1993 to 30,000 in 2001.