Manxman Gary Carswell, 45, crashed his Honda Fireblade in the opening practice session of the Jurby Motodrome racing meet and was fatally injured.
Mr Carswell, who worked for Manx Utilities, died at Noble's hospital.
Fellow competitor and close friend Paul Duckett said he "loved everything about life and approached it with open arms".
An investigation into the crash has been launched, said the Andreas Racing Association, which passed on its sincere condolences to Mr Carswell's family and friends.
Mr Duckett said his friend was one of the best people you could ever come across, and somebody who would always try to help you.
"He took everything on with open arms and will be sadly missed," Mr Duckett said.
Manx Radio Sport commentator Dave Christian, who knew Mr Carswell for 35 years, said he was an "incredibly likeable and chirpy character who lived for his motorcycle racing - the world is a much poorer place without him."
He finished third in the 2004 Senior TT and won the 1997 Senior Manx Grand Prix.
Tributes have been paid to a TT rider and Senior Manx Grand Prix winner who died on Saturday after a practice race crash on the Isle of Man.