Staff is seen here at the weekend's British Bicycle Awards picking up a gong from Hugh Porter.
The GT deal see Staff riding a GT Ultrabox BMX, a GT Ruckus MTB and GT will provide him with a road bike for non-track training.
Staff, originally a BMX racer, tried his hand at track and won bronze and silver medals at last year's Commonwealth Games, followed by a gold medal in the World Championships in Copenhagen.
Russell Merry of Hot Wheels, the GT importer, said:
"We are delighted to have Jamie on the team. Understandably his main focus is on the Olympics where he will not be riding a GT, but we believe he can be a force to be reckoned with at whatever discipline he chooses."