<html> Hi Mark,             &nbs= p; Some older Yamaha's had a centre pin plating problem, if you look at the pins under a magnifying glass you will see score lines on them and some flaking. The only solution is to ream all bushings and re centre pin 2 sizes over. This will get the crud out of the cloth, I also blow them out with compressed air.  About 25yr old vintage. Roger At 08:06 AM 5/4/01 -0400, you wrote: <blockquote type=cite cite>  I had a customer complain about the touch on their Yamaha grand and discovered that it weighted off at 66 grams at middle C. When I checked the hammer flange I found that I could only get one swing, and that the bushings had a black residue on them. Closer inspection showed that this residue was also on the center pins as well as slightly in the wood surrounding the bushings. The residue on the pins themselves rubbed right off, and the pins looked shiny and new without any signs of buildup or corrosion. I repinned one to normal tolerances and the cloth felt as if it had normal resiliency, and the downweight dropped by 11 grams. I also found that the wippen flanges had the same residue, but hadn't seized up the way the the hammer flanges had. They seemed to be *slightly* on the tight side but still within normal tolerances (I didn't have my little spring gage with me). The jack & rep lever bushings were normal bright red cloth, and perfectly free.   I have an appointment to return and repin this action, but before I do I wondered if anyone else has run across this before. Could this be something that Yamaha did at the factory? although I've certainly never seen it in their other grands, this is the first S series grand that I've serviced. The customer bought it used last year and so doesn't know it's history. Does anyone know of any center pin lubricants that react in this way? Is the problem likely to return after repinning? The serial # is: U3894763 Thanks, Mark Dierauf </blockquote> </html>