On the subject of your crankshaft;
Honda advises vertical movement no more than .004in. and side play or
Axial clearance of .0193in. These measurements are taken at the back side
of the lower end of the rod. Side clearance is accomplished with a feeler
gauge on the side of the rod closest to the connecting shaft.
I do a little prep first. Carb cleaner in the small holes in the center
rollers, and along side of the rods them selves. Then blow dry with
compressed air, do not allow the bearings to rotate freely. Then fill the
crankshaft with 20W30 oil. Watch for metal chips to flow from the side of
the pistons and center rollers. Now make your tests, measure the side
clearance and up and down movement. We know there is side play allowed,
however any noticeable clearance in vertical movement is a dark sign to
come. This is a critical issue, If you think their is some movement, fill
the crank back up with 20W50 and with a small plastic or hard rubber hammer,
hit the back side of the rod, if there is no metal (sound, movement followed
by a metal to metal connecting feel as you hold the rod and hit the back
side) Then it is a usable crank. If you see chips, feel the metal to metal
connection, hear the metal to metal ting, then it is better to move on to
the next crank and perform the same test on it.
Bill