Panchop, its my interpretation of the FIM rules that no part can extend past the rear WHEEL. I can't believe that's not meant to be rear TIRE. But here it is:
2.81 ADDITIONAL SPECIFICATIONS FOR SPECIAL VEHICLES USED FOR WORLD RECORDS (SHORT DISTANCE)
81.01 General
No part of a motorcycle (with the exception of extreme aerodynamic vehicles, also known as "Streamliners") may extend beyond the wheels. No airfoils, spoilers or movable external control surfaces are allowed."