Maybe this is what he is referring to:
From HD Tech Tip 324 (posted on this site in entirety)
1. Primary Drive Inspection
Remove the primary cover and inspect the driveline.
• Compensating sprocket assembly, Visual damage, Chain run-out
Excessive run-out (tight to loose spots) is one symptom of a shifted left side
crankshaft half
2. Inspection of the left side crankshaft run-out requires a dial indicator, magnetic base
and an angle iron mounting plate, and tools to remove the compensating assembly.
3. Crankshaft run-out inspection procedures
• Remove the spark plugs and primary chain tensioner assembly
A late model primary chain auto-tensioner will need to be “reloaded” prior to
reinstallation, per Section 6 of the appropriate Service Manual
• Remove the compensating sprocket assembly, leaving the clutch in place
Reinstall the sprocket nut or bolt to rotate the engine during inspection.
• Mount the angle iron to the primary housing gasket surface and attach the
magnetic base for the dial indicator parallel to the gasket surface
• Position the indicator on the end of the shaft at 90° (in both directions) to ensure
an accurate reading
• Mark your start spot with a marker and zero the gauge
• You will measure directly off the high spot of the splines, and must be careful not
to knock the indicator out of zero while taking your readings
o Do not bolt on the shaft adapter and attempt to reads off its surface, or attempt to
use anything threaded into the shaft. This will provide excessive run-out readings
as you are not precisely on center.
o Ignore the low “spikes” you will see on the dial indicator when it drops into the
“valleys” of the splined shaft. You are only interested in comparing the
differences in height of the high spots of the splines to determine total run-out.
o Don’t worry if you miss one or two of the ten to twenty-four teeth. You should still
be able to determine if the Service Wear Limit has been exceeded.
• The Service Wear limit of the left crankshaft in the crankcase is 0.012”
If your reading exceeds 0.012” and is under warranty stop and contact Technical
Service to discuss the appropriate repair or inspection procedures before continuing.
If the vehicle is out of warranty you will need to discuss the appropriate repair with the
customer (ESP coverage, flywheel replacement, dealer level rebuild, or factory Reman).
In order to take a more accurate reading of the crankshaft run-out it will require
removing the flywheels from the crankcases.