T.T. winner Dean Harrison is to leave RC Express Racing.
The 25 year-old joined the Bristol-based team in 2012 and together they have enjoyed considerable success.
The highlight was his maiden T.T. victory in this years' Lightweight Race.
Dean also clocked his first lap of over 130mph in the Senior from a standing start and won five of seven races at the Southern 100 in July.
He also won the Cock o' the North Trophy at Oliver's Mount in Scarborough in 2013 and 2014.
Harrison rode for Mar-Train in the two Supersport races at this year's T.T. - Mar-Train have been named as the official Yamaha team for road racing next season.