PRIMO'S RETRO-FIT STARTER MOTOR PINION GEAR FOR BIG TWIN 1994-1997This retro fit starter motor pinion gear is uniquely designed and manufactured to be compatible with 1994 2006 starter extension assemblies only, while allowing the use of the much stronger 1990 1993 style 66 tooth ring gear. A must for Big Cubic Inch and High Performance motors as these put additional stress on these critical components, particularly when the motor back fires during start up. Pinion gear and starter ring must be ordered separately.