@HondaMan can I get the same outcome of measuring wiggle if I measure the bore of the guides and the stem size and subtracting the two? Currently waiting on shipping for a proper dial gauge to get into the head to measure wiggle.
Here is what I measured:
Bore size on EX: 0.2600
Bore size on INT: 0.2602
Stem size on EX valve: 0.2580
Stem size on INT valve: 0.2590
Taking those along with the 0.0032 wiggle spec. I should be OK right?
I obviously will be doing the wiggle test when I get in the dial gauge but I couldn't wait another few days to keep digging into the head.
Couldn't find an official spec on the stem size of the valves
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It's real hard to measure them that way because of the wear angle. Imagine, for example, if you sawed a head in half thru the guides (which I might do to one I have here that is otherwise not usable), you would see that the wear is on the outside of the guides at their tops and the inside (toward chamber center) at the bottom. This is due to the angle of the rockers and how they slide back-and-forth across the tips of the valves during an opening-closing cycle: it loads the outside as the valve begins to open, then the washed-off (by gasoline) valve stem in the intake passage grinds its way closed against the center-of-head side of the guide at the bottom. So, the wear is measured in that axis, which tries to take into account the wear at the top AND bottom of the guide. With new clearance of 0.0012" stem-to-guide, this comes out to 0.0024" of 'wiggle' from center-of-head toward intake port, measured with a dial gage. Honda spec'd 0.0032" as worn-out, but I have found they run fine until 0.0045" or so if the valve seals are still soft and pliable. On the exhaust side the stock clearance is 0.0020", so the wiggle starts at 0.0040" there, and by about 0.0070" or so they start to leak oil and make messy exhaust ports, even with new seals.
So, it's really hard to try to measure them any other way.
