Bob,
I might not have the years of experience you have at rebuilding WBX engines,
But on the few that I have taken apart, I have seen the center main bearing
saddle case fretting like the T1 engines.  On another engine I saw rod
bearing wear consistent with my thinking that the increased stroke is the
real problem not so much the bolts.  The rod bearing was worn at an angle
(one side more than the other) and it was consistent with the location of the
rod on the crank.  The bearing was worn and you saw the copper colored metal
under the top layer of the bearing in the shape of a triangle.

Can you explain just how the rod bolts stretch over thousands of miles,
allowing the cap to bend and but the nuts do not back off?  Like I said, I
can see the nuts coming off the rods

From my experience the slightest reduction in torque will allow harmonic
vibrations to cause fasteners to back off in high stress environments: nuts
on the rocker arm stand, valve adjusting screw nuts, nuts on rods, case
bolts, etc.


The WBX engine is based on a T1 engine and suffers from some of the same
problems.



Robert