<< a Yamaha C3 that's 4 years old. It is like new, very slight knuckle/hammer wear, but really good shape. I have regulated it and everything seems great except that the let-off bump feel seems excessive and I can't figure out why, on this C3. >> Greetings, Move the jacks out from under the knuckle until they begin to skip on a moderately hard blow, then turn them back about 1 or 1/2 mm. Set the balancier until you can just barely feel the jack return under the knuckle leather. Springs should be set as strong as possible without being able to feel them in the key as they lift the hammer. That is about as much as you can do to reduce the resistance at let-off. Setting the drop at the same distance from the string as let-off will also help, but you have to have a consistant key dip first. Good luck, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html
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