Bearing sizes

Line Bore	Thrust???????	Crank
Std - 65mm	Std - 22mm	Std - 55mm
1st - 65.5mm	1st - 21mm	1st undersize - .25mm
2nd - 66mm	2nd - 20mm	2nd undersize - .50mm
3rd - 66.5mm		3rd undersize - .75mm
4th - 67mm		4th undersize - 1.00mm (54mm)
Crankshaft Converted To Inches
Mains	Rods	Conversion MM To Inches
Std - 2.1641 - 2.1649	Std - 2.1646 - 2.1654	.25mm = .010"
1st - 2.1541 - 2.1549	1st - 2.1546 - 2.1554	.50mm = .020"
2nd - 2.1441 - 2.1449	2nd - 2.1446 - 2.1454	.75mm = .030"
3rd - 2.1341 - 2.1349	3rd - 2.1346 - 2.1354	1.00mm = 040"
4th - 2.1241 - 2.1249	4th - 2.1246 - 2.1254

Courtesy of lazy8parts.com....with the additions of the mm size

1200cc-1600cc Crankshaft &; Bearing Information (May 1960 On)

Std. Rod Journal = 2.164" (54.9656mm)

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"  (55.0mm)
Std. Main Journal # 4 = 1.574" (39.9796mm?)

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" (65.0 mm)
If the case has been bored + .020" The dia = 2.579" (65.5 mm)
If the case has been bored + .040" The dia = 2.599" (66.0 mm)
If the case has been bored + .060" The dia = 2.619" (66.5 mm)
If the case has been bored + .080" The dia = 2.639" (67.0 mm)

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" (5.2705 mm)
If the case has been bored + .040" The Shell measures .2085" (5.2959 mm)

If the case has been bored + .060" The Shell measures .2095" (5.3213 mm)
If the case has been bored + .080" The Shell measures .2105" (5.3467 mm)

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" (21.9837 mm)
If the Thrust Bearing is - .040" The Width = 0.8255" (20.9677 mm)
If the Thrust Bearing is - .080" The Width = 0.7855" (19.9517 mm)

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 Thicknessof the "Outer" Rear Main Bearing Thrust Flange:

If the thrust is Std.
     The Outer Rear Thrust Flange thickness is 0.0965" (2.4511 mm)
If the thrust has been cut to -.040"
     The Outer Rear Thrust Flange thickness is 0.1365" (3.4671 mm)
If the thrust has been cut to -.080"
     The Outer Rear Thrust Flange thickness is 0.1765" (4.4831 mm)