There is the possibility of Milwaukee Yamaha riders Ian Hutchinson and Josh Brookes not competing at T.T. 2014.
T.T. organisers have confirmed Yamaha are unhappy with proposed changes to the rules on electronics......but BMW, Honda, Kawasaki and Suzuki support the revised regulations.
The move is designed to bring the rules in line with those at the British Superbike Championship and therefore reduce costs.
Changes to engine regulations have been put off until 2015.
Clerk of the Course for the T.T. Gary Thompson says organisers are in a difficult situation but have consulted widely with everyone since July:-Clip 1