Std. Rod Journal = 2.164"

The Crankshaft Main Bearing Journal closest to the Flywheel is Journal # 1 and is the Thrust Bearing.

Std. Main Journals # 1, # 2, & # 3 = 2.164"

Std. Main Journal # 4 = 1.574"

Journal Bearings # 1 & 4 are one piece and install on the Crankshaft

Journal Bearings # 2 & 3 are two piece and install in the case halves

To determine if a 1200cc/1600cc case has been align bored, measure the outside diameter of the rear main bearing shell:

If the case is Std. The dia = 2.559"

If the case has been bored + .020" The dia = 2.579"

If the case has been bored + .040" The dia = 2.599"

If the case has been bored + .060" The dia = 2.619"

If the case has been bored + .080" The dia = 2.639"

If you don’t have the one piece Rear Main Bearing Shell, you can measure the thickness of one of the # 2 or # 3 Main bearing Halves.

(To use this method, you have to know if the Crankshaft the bearing came from is: Std., .010", .020", etc. & adjust the following dimensions accordingly).

If the Crankshaft is Std. The thickness of the # 2 or # 3

Bearing shell Half in a Standard Case = .2065"

If the case has been bored + .020" The Shell measures .2075"

If the case has been bored + .040" The Shell measures .2085"

If the case has been bored + .060" The Shell measures .2095"

If the case has been bored + .080" The Shell measures .2105"

To determine if a 1200cc/1600cc case thrust has been cut, measure the width of the Case Rear Main Bearing Saddle:

If the Thrust Bearing is Std. The Width = 0.8655"

If the Thrust Bearing is - .040" The Width = 0.8255"

If the Thrust Bearing is - .080" The Width = 0.7855"

If you are trying to determine what oversize bearings to get for a crankshaft and don't have immediate access to the case, but have the old crankshaft complete with bearings, you can easily determine if a 1200cc/1600cc case thrust has been cut, by measuring the Thickness of the "Outer" Rear Main Bearing Thrust Flange:

If the thrust is Std.

       The Outer Rear Thrust Flange thickness is 0.0965"

If the thrust has been cut to -.040"

If the thrust has been cut to -.080"