As of 2016, the “quick disable” is the fastest, easiest, and cheapest way to convert a 600 to a 450 triple.


6.1.7 Disabled Cylinder Motorcycles

a)?A Disabled Cylinder Motorcycle is?a 600 Production or 600 Superbike motorcycle with a cylinder disabled to produce a 450Production or 450 Superbike motorcycle.

b) The cylinder disablement must include some physical modification to the engine (ex: cam lobes removed, valves removed, ?fuel injector(s) bypassed or spark plug removed).

c) The disabled cylinder’s fuel or spark (or both) must be disabled in a manner that is readily verifiable from outside the motor.

d) The disabled cylinder’s reciprocating mass may not be removed (ex: bob weighted crankshafts are not allowed).


Yamaha R4.5

{Write up coming May 2016}